Journal articles: 'Metal precursor'

1

Anderson, J. A., and M. Galan-Fereres. "Precursor-support interactions in the preparation of sepiolite-supported Ni and Pd catalysts." Clay Minerals 34, no. 1 (March 1999): 57–66. http://dx.doi.org/10.1180/000985599546073.

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AbstractNaturally occurring sepiolite has been used as a support in the preparation of Ni and Pd catalysts. A precipitation procedure has been applied for both metals to deposit the precursor on to the support surface. The interaction between the sepiolite and the metal precursor has been studied by use of IR and solid-state MAS-NMR. Results show that SiOH groups are consumed in forming the Ni precursor whereas no specific interactions occur in the case of the Pd. However, strong interactions between metal precursor and the tetrahedral sheet occur for both metals leading to precursors which show a high stability under reducing conditions.

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Fukuda, Nobuko, Shintaro Ogura, Ken-ichi Nomura, and Hirobumi Ushijima. "Effects of Amines on Chemical and Physical Behaviors of Viscous Precursor Sols to Indium Gallium Zinc Oxide." MRS Proceedings 1547 (2013): 123–28. http://dx.doi.org/10.1557/opl.2013.783.

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ABSTRACTWe synthesized viscous precursors to indium gallium zinc oxide (IGZO) using three kinds of alcoholamines, ethanolamine (EA), diethanolamine (DEA), and triethanolamine (TEA), by a simple process. The viscous precursors are obtained just by vigorous stirring of alcoholamine and urea in an aqueous solution containing the metal nitrates during heating at 150-160 °C. The precursor containing EA (EA-precursor) is a pale-orange suspension containing aggregates of the metal hydroxides and shows pseudoplastic flow. The precursors containing DEA (DEA-precursor) and TEA (TEA-precursor) are transparent pale-yellow and dark-orange sols, respectively. They give Newtonian flow in the lower shear rate and pseudoplastic flow in the higher shear rate. Higher concentration of metal salts leads to higher viscosity of the precursors. According to thermogravimetry-differential thermal analysis (TG-DTA) for the EA- and DEA-precursors, evaporation of alcoholamine occurs at around each boiling point and subsequently formation of metal oxides occur at around 300 °C. In the case of the TEA-precursor, formation of metal oxides occurs before pyrolysis of TEA attributed to the higher boiling point of TEA. The thin IGZO film, which is prepared by spin-coating of the diluted DEA-precursor and subsequent sintering at 450 °C for 30 min, shows 0.02 cm2 ·V-1s-1 of the mobility and 10-5 of the on/off ratio. The highly viscous DEA-precursor containing high concentration of metal ions allows patterning in an area of 100 cm2 onto a surface of a silicon wafer with screen printing.

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Antony, M. M., and K. H. Sandhage. "Barium titanate/noble metal laminates prepared by the oxidation of solid metallic precursors." Journal of Materials Research 8, no. 11 (November 1993): 2968–77. http://dx.doi.org/10.1557/jmr.1993.2968.

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A novel and attractive method for preparing multicomponent electronic ceramics and ceramic-metal composites is the oxidation of solid metallic precursors (SMP). This metallurgical processing route consists of the following steps: (i) preparation of a solid metallic precursor containing the proper ratio of elements for the final ceramic or ceramic-metal composite, (ii) compaction and forming of the metallic precursor into a desired shape, and (iii) oxidation to produce a monolithic ceramic or ceramic-metal composite. While the SMP method has been used to prepare wires and tapes containing a variety of superconducting oxides, this method has not been widely used to synthesize other electronic ceramics. In this paper, the synthesis of dielectric BaTiO3/noble metal laminates from solid metallic precursors is discussed. Ba–Ti precursor powders have been produced by solid-state mechanical alloying. The precursor powder was sealed inside noble metal tubes and rolled to form thin Ba–Ti/noble metal laminates. Exposure of the Ba–Ti core in such tapes to temperatures ≥ 300 °C in pure oxygen resulted in rapid oxidation. Post-oxidation annealing at elevated temperatures (≥900 °C) yielded dielectric BaTiO3/Ag or BaTiO3/Pd laminates.

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Allameh, Seyed M., and Kenneth H. Sandhage. "The oxidative transformation of solid, barium-metal-bearing precursors into monolithic celsian with a retention of shape, dimensions, and relative density." Journal of Materials Research 13, no. 5 (May 1998): 1271–85. http://dx.doi.org/10.1557/jmr.1998.0182.

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The conversion of Ba–Al2O3 –Si–SiO2, Ba–Al–Al2O3 –SiO2, and Ba–Sr–Al–Al2O3 –SiO2 precursors into monolithic, monoclinic celsian has been examined. The relative amounts of metal and oxide in each type of precursor were adjusted so that the overall stoichiometry and molar volume were similar to those of the desired product, celsian. Metal + oxide mixtures were mechanically alloyed and then uniaxially pressed to yield 84–92% dense precursor disks. The precursors were converted into celsian by exposure to a series of heat treatments from 300–1500 °C in oxygen-bearing gases. Differences and similarities in the phase evolution of the various precursors are discussed. Celsian disks were produced that retained the precursor shape, dimensions, and relative (% theoretical) density.

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Tan, Koon Tatt. "Review on Manufacturing of Metal Foams." ASM Science Journal 16 (July 26, 2021): 1–8. http://dx.doi.org/10.32802/asmscj.2021.794.

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Metal foams possess excellent physical and mechanical properties. This paper reviews the common manufacturing process of metal foams. Various ways used to produce metal foams based on metal properties are described. The manufacturing process follows four primary routes: liquid state, solid state, ion or vapour processing. Liquid-state processing produces porosity to liquid or semi-liquid metals, and solid-state foaming produces metal foams with metal powder as starting material. For ion and vapour processing methods, metals are electro-deposited onto a polymer precursor. The polymer precursor is removed by chemical or heat treatment to produce metal foams. The advantages and limitations of each manufacturing process are also described.

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Matus, E. V., L. M. Khitsova, O. S. Efimova, S. A. Yashnik, N. V. Shikina, and Z. R. Ismagilov. "Preparation of Carbon Nanotubes with Supported Metal Oxide Nanoparticles: Effect of Metal Precursor on Thermal Decomposition Behavior of the Materials." Eurasian Chemico-Technological Journal 21, no. 4 (December 18, 2019): 303. http://dx.doi.org/10.18321/ectj887.

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To develop new catalysts based on carbon nanomaterials with supported metal oxide nanoparticles for oxidative transformations of sulfur compounds, a series of metal oxide nanoparticle-decorated carbon nanotubes (MOx/CNTs) were prepared by incipient wetness impregnation at a variation of the active metal type (M = Ce, Mo, Cu). The thermal decomposition of bulk and CNT supported metal precursors used in the preparation of MOx/CNTs was analyzed under inert atmosphere employing several thermoanalytical techniques (thermogravimetry, differential thermogravimetry and differential scanning calorimetry) coupled with mass spectrometry. The thermolysis parameters of the bulk and supported metal precursors were compared and the effect of CNT support on the decomposition pattern of compounds was elucidated. It was established that the decomposition of metal precursors supported on CNTs was started and completed at temperatures of 15‒25 and 25‒70 °C lower, respectively, compared with the bulk active metal precursor. The enhancement of CNT support stability against thermal degradation is observed in the following row of metal cations: Ce < Cu < Мо < pristine and metal anions of precursor: nitrate < chloride < sulfate. The optimal mode of thermal treatment of catalyst and appropriate active metal precursors were selected for advanced synthesis of nanosized MOx/CNT catalyst.

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Deng, Chong, Bowen Fu, Lili Li, Yanlai Wang, and Lin Yang. "Influence of Sulfur Precursor Solutions on Crystallinity of CuInS2 Nanocrystals Fabricated with Hot-Injection Method." Journal of Nanoscience and Nanotechnology 20, no. 7 (July 1, 2020): 4533–36. http://dx.doi.org/10.1166/jnn.2020.17894.

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The hot-injection method was used for the synthesis of ternary metal chalcogenide nanocrystals (NCs) CuInS2 (CIS); this was achieved by using the metal precursors (copper iodide and indium acetate) and four different types of sulfur precursor solutions. It was discovered that CIS NCs synthesized with different sulfur precursor solutions exhibited the chalcopyrite structure with similar particle sizes of ~4.2 nm. As a comparison, CIS NCs synthesized using ODE-S precursor displayed an enhanced luminescence intensity and a long PL decay lifetime, which could be considered as an evidence of improved interior crystallinity.

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Yakushko, E. V., L. V. Kozhitov, D. G. Muratov, D. Yu Karpenkov, and A. V. Popkova. "The controllable magnetic properties of Nico/C nanocomposites." Izvestiya Vysshikh Uchebnykh Zavedenii. Materialy Elektronnoi Tekhniki = Materials of Electronics Engineering 22, no. 2 (December 10, 2019): 92–103. http://dx.doi.org/10.17073/1609-3577-2019-2-92-103.

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The NiCo/C metal-carbon nanocomposites based on the NiCl2/CoCl2/Polyacrylonitrile (PAN) precursors were synthesized using IR heating. The results of studies of NiCo/C nanocomposites by X-ray phase analysis, transmission electron microscopy, and vibration magnetometry showed the dependence of the structure and properties of NiCo/C nanocomposites on the synthesis temperature, concentration, and metal ratio in the precursor. According to the results of the X-ray phase analysis, it was found that during the IR pyrolysis of the precursor, NiCo metal nanoparticles are stabilized in the carbon matrix, an increase in the synthesis temperature from 350 to 800 °C leads to an increase in the average size of nio nanoparticles from 10 to 80 nm, it is established that the formation of the alloy occurs due to the gradual dissolution of cobalt in nickel with the simultaneous transition of cobalt from the hcp modification to FCC. The structure of nanocomposites was shown by transmission electron microscopy of samples synthesized at 600 °C. It was found that with an increase in the metal concentration in the precursor from 10 to 40 wt.%, the average size of NiCo nanoparticles increases and the concentration of nanoparticles in the carbon matrix increases. The study of the magnetic properties of nanocomposites showed that with an increase in the content of metals in the precursor from 10 to 40 wt.%, an almost linear increase in the saturation magnetization from 5.94 to 25.7 A · m2/kg is observed. A change in the ratio of metals from Ni : Co = 4 : 1 to Ni : Co = 1 : 4 causes an increase in magnetization from 11.46 to 23.3 A · m2/kg.

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Murugkar, Anupa, Subhash Padhye, Sujata Guha-Roy, and Ullas Wagh. "Metal complexes of Taxol precursor." Inorganic Chemistry Communications 2, no. 11 (November 1999): 545–48. http://dx.doi.org/10.1016/s1387-7003(99)00152-5.

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10

Qiu, Yu, and Lian Gao. "Metal-Urea Complex-A Precursor to Metal Nitrides." Journal of the American Ceramic Society 87, no. 3 (March 2004): 352–57. http://dx.doi.org/10.1111/j.1551-2916.2004.00352.x.

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11

Hayashi, Tsugumi, Yohei Baba, Toshiharu Taga, Shun Yokoyama, Hiroaki Suzuki, Hideyuki Takahashi, Masayuki Niino, and Kazuyuki Tohji. "Effect of Metal Gradient In Nano Wall of Stratified Type Photocatalyst." Materials Science Forum 631-632 (October 2009): 339–44. http://dx.doi.org/10.4028/www.scientific.net/msf.631-632.339.

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Objective of study was the development of core-shell type ZnS-CdS photocatalyst with the stratified morphology. To form the stratified morphology, condition of the precursor is extremely important. For this purpose, three types of precursors, thus core-shell type, egg-shell type and uniform type, was tried to synthesize by utilizing the results of the calculation. The size of the synthesized precursor particles was about 40-100 nm. Main phase of the particle was gradually changed from ZnO (pH8.0) to Cd(OH)2 (pH9.5). Detailed analysis of the synthesized precursor was clearly demonstrated that these have the crystalline structure and each metal element was co-existed in one particle. Therefore, it could be concluded that core-shell type or uniform type precursor was successfully synthesized. Core-shell type ZnS-CdS stratified photocatalyst could be successfully synthesized by sulfurization for 1h, and it shows the high photocatalytic activity under visible light irradiation.

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12

Choi, Byeong-Min, Seok-Hwan Son, Chul-Wee Lee, Sun-Yeong Park, and Min-Chul Chung. "Characterization and Synthesis of Molybdenum Metal Precursors for Hydrocracking Reaction of Vacuum Residues." Journal of Nanoscience and Nanotechnology 20, no. 9 (September 1, 2020): 5787–90. http://dx.doi.org/10.1166/jnn.2020.17650.

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In this study, Molybdenum precursors were synthesized with Triphenylphosphine, 1,2-Bis(diphenylphosphino)ethane, Pyridine, 2,2-Bipyridine as a ligands. The molybdenum precursors was used for Hydrocraking reaction of Vacuum Residue (VR). Hydrocracking reactions were carried out under the 430 °C and H2 pressure of 80 bar in an 100 ml high pressure reactor. New Molybdenum precursors were tested and their activities were compared with Mo-octoate. The Molybdeum-Phosphine precursor showed the best performances, high yield and low coke contents (below 0,5 wt%), in of hydrocracking for VR. To characterize the physicochemical properties of Moprecursor catalyst, various characterization techniques (NMR, XPS) were carried out. We confirmed that cokes in the reactor were contained the P atoms derived from ligand of Mo-precursor after hydrocracking of VR.

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13

Rao, Lin, Edward G. Gillan, and Richard B. Kaner. "Rapid synthesis of transition-metal borides by solid-state metathesis." Journal of Materials Research 10, no. 2 (February 1995): 353–61. http://dx.doi.org/10.1557/jmr.1995.0353.

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A rapid self-sustaining solid-state precursor route to transition-metal borides, boride solid solutions, and boride composites has been developed. Solid-state metathesis (SSM) reactions between transition-metal chlorides and magnesium boride (MgB2) produce crystalline borides and magnesium chloride. Boride solid solutions are formed using mixed chloride precursors. By using a third precursor, such as NaN3, boride-nitride composites are synthesized. The reaction products are characterized by powder x-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, and inductively coupled plasma atomic absorption spectroscopy. These boride reactions become self-propagating when the adiabatic temperature is greater than the melting point of the by-product salt, MgCl2 (mp 987 K).

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Laine, Richard M., Kay A. Youngdahl, Richard A. Kennish, Martin L. Hoppe, Zhi-Fan Zhang, and Jean Ray. "Superconducting fibers from organometallic precursors. Part II: Chemistry and low temperature processing1." Journal of Materials Research 6, no. 5 (May 1991): 895–907. http://dx.doi.org/10.1557/jmr.1991.0895.

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Working principles are developed as guidelines for the selection and/or design of organometallic polymers for processing fiber precursors to metal oxide fibers. These principles form the basis for the selection of metal carboxylate preceramics as an optimal approach to processing yttrium barium cuprate (123) ceramic superconducting fibers. A variety of candidate yttrium, barium, calcium, strontium, bismuth, and copper metal carboxylates were synthesized. Solubility and empirical rheology tests were conducted to screen these compounds to choose spinnable precursor systems. Simple extrusion studies confirmed that THF solutions of mixtures of yttrium, barium, and copper isobutyrates with some quantity of barium 2-ethyl-hexanoates can be used to successfully form 60–70 μm diameter 123 precursor fibers.

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Higuchi, Mai, Mizuri Yaguchi, Miru Yoshida-Hirahara, Hitoshi Ogihara, and Hideki Kurokawa. "Facile synthesis of nanostructured perovskites by precursor accumulation on nanocarbons." RSC Advances 12, no. 10 (2022): 6186–91. http://dx.doi.org/10.1039/d1ra08357k.

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Various nano-perovskites are synthesized by dropping a precursor solution of metal salts into nanocarbon, followed by drying and calcination in air. The accumulation of precursors on the surface of nanocarbon is the key step.

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Sreeja, R., P. V. Prabhakaran, Sushant K. Manwatkar, and S. Packirisamy. "Adhesive Joining of Metal to Metal and Metal to Ceramic by Ceramic Precursor Route." Materials Science Forum 710 (January 2012): 656–61. http://dx.doi.org/10.4028/www.scientific.net/msf.710.656.

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Inorganic ceramic adhesives (geopolymers) based on aluminosilicate matrix are versatile candidates for bonding metals to metals or metals to ceramics. On curing, they result in an amorphous, crosslinked, impervious, acid resistant 3D-structures. Alkali activated aluminosilicate based ceramic adhesive was developed for bonding metals to ceramics and metal to metal, for high temperature applications. The bonding is achieved at 175°C for 3 hrs, by solid state reaction of alkaline solution of allkalisilicate precursor with the refractory filler, contributing to the bulk aluminosilicate matrix. Lap shear strength of 2-4 MPa was obtained for bonding stainless steel. The XRD patterns show the amorphous nature of the aluminosilicate matrix, with mullite formation at higher temperatures. Thermogravimetric analysis shows that the weight loss is only due to the removal of water from the system by means of evaporation and polycondensation of Si-OH groups and Al-OH groups. This is followed by structural reorganisation in which aluminium ions are incorporated into the silicate chains forming the Si-O-Al network resulting in the bonding with the metallic surface. The system can withstand the maximum operational temperatures of the substrates and can be used for bonding different metallic or ceramic, joints/interfaces for RLV-TD/TSTO.

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YANG, DANIEL, and SANG-WHA LEE. "PHOTOCATALYTIC ACTIVITY OF Ag, Au-DEPOSITED TiO2 NANOPARTICLES PREPARED BY SONOCHEMICAL REDUCTION METHOD." Surface Review and Letters 17, no. 01 (February 2010): 21–26. http://dx.doi.org/10.1142/s0218625x10013588.

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The photocatalytic activity of metal-deposited TiO 2 was investigated with different surface coverage of nanosized noble metals ( Ag and Au ). The sonochemical deposition of nanosized metals on the TiO 2 matrix was prepared by adjusting the loading volumes of silver and gold precursors in an ultrasound-driven cell. Non-annealed Ag-TiO 2 exhibited the maximal activity in the optimal loading ranges of silver precursor (e.g. 0.2–0.3 ml of 1.0 wt.% AgNO 3), displaying the enhanced efficiency of electron–hole separation. The addition of nanosized Au on Ag-TiO 2 proved to be undesirable to improve the photocatalytic activity of Au/Ag-TiO 2, except for the excessive loading of metal precursors (0.3 ml of 1.0 wt.% AgNO 3 + 0.2 ml of 1.0 wt.% HAuCl 4). XRD and XPS analysis confirmed the co-existence of Ag and Au species, and the reduction of PL (photoluminescence) intensity indicated the efficient separation of electron–hole pairs for optimal doping of nanosized metals on the TiO 2 matrix.

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Veith, Michael, S. Kneip, S. Faber, and E. Fritscher. "Metal/ Metal Oxide Composites by Single Source Precursor CVD." Materials Science Forum 269-272 (January 1998): 303–6. http://dx.doi.org/10.4028/www.scientific.net/msf.269-272.303.

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Hamzah, Noraini, Aznira Alias, Wan Zurina Samad, Mohamad Bin Kassim, and Mohd Ambar Yarmo. "Effect of Ruthenium Metal Precursors Supported on Bentonite in Hydrogenolysis Glycerol." Advanced Materials Research 173 (December 2010): 134–39. http://dx.doi.org/10.4028/www.scientific.net/amr.173.134.

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Various ruthenium precursors (Ru= RuCl3, Ru2 = Ru(acac)3, Ru3 = Ru3(CO)12) supported on bentonite were prepared by conventional impregnation method. Their catalytic performances were evaluated in the hydrogenolysis of glycerol using autoclave Parr reactor under mild reaction conditions of 150°C, hydrogen pressure 30 bar for 7 hours. Among the studied catalyst, 5% Ru/bentonite catalyst prepared from Ru and Ru3 precursor exhibited higher activity which are 79.6% and 72.5% respectively. In contrast, Ru2/bentonite prepared from Ru(acac)3 precusor gave lowest activity (41.8%). In term of selectivity to 1,2-propanediol, Ru2 and Ru3 precusor gave higher selectivity (67.0% and 66.9%) compared to Ru precursor (50.6%). These results indicated that metal precursor plays an important role on activity and selectivity of the catalyst in hydrogenolysis reaction. The catalysts were characterized by XRD, XPS, BET, FESEM-EDX and TEM, and the reasons for the high performances of the catalyst were also discussed.

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Kim, Donghan, Jinsub Lim, Vinod Mathew, Bonil Koo, Younkee Paik, Docheon Ahn, Seung-Min Paek, and Jaekook Kim. "Low-cost LiFePO4using Fe metal precursor." J. Mater. Chem. 22, no. 6 (2012): 2624–31. http://dx.doi.org/10.1039/c2jm14499a.

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Parvizian, Mahsa, and Jonathan De Roo. "Precursor chemistry of metal nitride nanocrystals." Nanoscale 13, no. 45 (2021): 18865–82. http://dx.doi.org/10.1039/d1nr05092c.

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Hussainov, Medhat, Tanel Tätte, Madis Paalo, Jonas Gurauskis, Hugo Mändar, and Ants Lõhmus. "Structure and Rheological Behavior of Alkoxide-Based Precursors for Drawing of Metal Oxide Micro- and Nanofibres." Advanced Materials Research 214 (February 2011): 354–58. http://dx.doi.org/10.4028/www.scientific.net/amr.214.354.

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The aim of this study is investigation of the influence of the method of metal alkoxy precursors preparation on their rheological characteristics and spinability for metal oxide fibre drawing. The precursor samples were obtained from tin 1-butoxide Sn(OBu)4 as a result of aqueous (AQ) and non-aqueous (NAQ) (thermolysis) treatment. Small angle X-ray scattering (SAXS) data of precursors in the range of scattering vector modulus 0.07–5.3 nm-1 were recorded on a slit collimation camera KRM-1 by using Cu Kα radiation and NaI:Tl scintillation detector. Program system ATSAS [1] was used for calculation of the radius of gyration Rg and for 3D modeling of the cluster shape. The rheological characterization of samples was conducted with a help of a rotational rheometer Mars II (Haake, Karlsruhe, Germany) equipped with plate-and-plate test geometry (plate diameter 20 mm). The precursors studied in this work consist of the elongated particles of 3 – 5 nm in length and 2 nm in diameter for both AQ and NAQ prepared precursors. Rheological tests have proved that the solvent free precursors are typical non-Newtonian fluids. Precursors obtained with the help of NAQ treatment are more elastic as compared to those prepared with AQ procedure. Surface tension (ST) measurements show that the coefficient of ST of NAQ prepared precursor is 45% lower than that of AQ prepared one. Fibres with aspect ratio up to 10000 and diameter of 200 nm were directly drawn from the NAQ precursors at room temperature in standard lab atmosphere. AQ prepared precursor allows obtaining of the fibers of minimum 500 nm in diameter with maximal aspect ratio 1000.

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Belot, John A., Richard J. McNeely, Anchuan Wang, Charles J. Reedy, Tobin J. Marks, Glenn P. A. Yap, and Arnold L. Rheingold. "Expedient route to volatile zirconium metal-organic chemical vapor deposition precursors using amide synthons and implementation in yttria-stabilized zirconia film growth." Journal of Materials Research 14, no. 1 (January 1999): 12–15. http://dx.doi.org/10.1557/jmr.1999.0004.

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This communication reports rapid, efficient syntheses of the zirconium-organic metal-organic chemical vapor deposition (MOCVD) precursors Zr(acac)4 and Zr(dpm)4 (acac = acetylacetonate; dpm = dipivaloylmethanate) as well as a new, highly volatile, air- and moisture-stable Zr precursor based on a tetradentate Schiff-base ligand, Zr(tfacen)2 (tfacen = bis-trifluoroacetylacetone-ethylenediiminate). The improved one-step synthetic routes employ tetrakis(dimethylamido)zirconium as a common intermediate and represent a major advance over previous methods employing ZrCl4 or diketonate metathesis. Furthermore, Zr(tfacen)2 is shown to be an effective metal-organic precursor for the MOCVD-mediated growth of (100) oriented yttria-stabilized zirconia thin films.

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Kurek, Agnieszka, Peter G. Gordon, Sarah Karle, Anjana Devi, and Seán T. Barry. "Recent Advances Using Guanidinate Ligands for Chemical Vapour Deposition (CVD) and Atomic Layer Deposition (ALD) Applications." Australian Journal of Chemistry 67, no. 7 (2014): 989. http://dx.doi.org/10.1071/ch14172.

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Volatile metal complexes are important for chemical vapour deposition (CVD) and atomic layer deposition (ALD) to deliver metal components to growing thin films. Compounds that are thermally stable enough to volatilize but that can also react with a specific substrate are uncommon and remain unknown for many metal centres. Guanidinate ligands, as discussed in this review, have proven their utility for CVD and ALD precursors for a broad range of metal centres. Guanidinate complexes have been used to deposit metal oxides, metal nitrides and pure metal films by tuning process parameters. Our review highlights use of guanidinate ligands for CVD and ALD of thin films over the past five years, design trends for precursors, promising precursor candidates and discusses the future outlook of these ligands.

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Kim, Jae Young, Geonoh Choe, Tae Kyu An, and Yong Jin Jeong. "Study of Self-Patterned Zinc Tin Oxide Thin-Film Transistors Prepared from Photocurable Precursor Solution with Photoacid Generator." Korean Journal of Metals and Materials 59, no. 3 (March 5, 2021): 162–67. http://dx.doi.org/10.3365/kjmm.2021.59.3.162.

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Solution-processed zinc tin oxide (ZTO) thin-film transistors (TFTs) have great potential uses in next-generation wearable and flexible electronic products. Zinc and tin precursor materials are naturally abundant and have low fabrication costs. To integrate a single ZTO TFT into logic circuits including inverters, NAND, and NOR gates will require the development of a facile patterning process to replace conventional and complicated photolithography techniques which are usually time-consuming and toxic. In this study, self-patterned ZTO thin films were prepared using a photo-patternable precursor solution including a photoacid generator, (4-methylthiophenyl)methyl phenyl sulfonium triflate. Solution-processed ZTO precursor films fabricated with the photoacid generator were successfully micropatterned by UV exposure, and transitioned to a semiconducting ZTO thin film by heat treatment. The UV-irradiated precursor films became insoluble in developing solvent as the generated proton from the photoacid generator affected the metal-containing ligand and changed the solubility of the metal oxide precursors. The resulting ZTO thin films were utilized as the active layers of n-type TFTs, which exhibited a typical n-type transfer, and output characteristics with appropriate threshold voltage, on/off current ratio, and field-effect mobility. We believe that our work provides a convenient solution-based route to the fabrication of metal-oxide semiconductor patterns.

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Malinowska, Izabela, Zuzanna Ryżyńska, Eryka Mrotek, Tomasz Klimczuk, and Anna Zielińska-Jurek. "Synthesis of CoFe2O4 Nanoparticles: The Effect of Ionic Strength, Concentration, and Precursor Type on Morphology and Magnetic Properties." Journal of Nanomaterials 2020 (May 5, 2020): 1–12. http://dx.doi.org/10.1155/2020/9046219.

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The present study highlights the effect of metal precursor types (SO42¯, Cl¯, and NO3¯), their concentration, and the influence of ionic strength of reaction environment on the morphology, surface, and magnetic properties of CoFe2O4 particles. The magnetic nanoparticles were obtained by chemical coprecipitation in alkaline medium at increasing metal concentration in the range of 0.0425 mol·dm-3 to 0.17 mol·dm-3 and calcination temperature from 400°C to 800°C. It was found that the chemistry of precursors can be directly correlated with magnetic properties. The CoFe2O4 particles from metal sulphate precursors showed the highest saturation magnetization and the lowest coercivity. The adjustment of ionic strength in the range of 1.25–5 M was achieved by adding an appropriate quantity of metal sulphates into aqueous solutions at a constant pH or by adding an appropriate quantity of NaClO5 under similar conditions. The average hydrodynamic size of CoFe2O4 increased from 46 nm to 54 nm with increasing metal concentration and ionic strength. An explanation of magnetic properties, caused by ionic strength and metal concentration, is given based mainly on the reduction in repulsive forces at the particle interface and compensation of the double electric layer in the presence of anions. The observed coercivity was lower for the particles obtained in solutions with the highest ionic strength, whereas the concentration of metals and calcination temperature affected the saturation magnetization and morphology of the obtained cobalt ferrite particles.

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WENDEL, H., H. HOLZSCHUH, H. SUHR, G. ERKER, S. DEHNICKE, and M. MENA. "THIN ZIRCONIUM DIOXIDE AND YTTRIUM OXIDE-STABILIZED ZIRCONIUM DIOXIDE FILMS PREPARED BY PLASMA-CVD." Modern Physics Letters B 04, no. 19 (October 20, 1990): 1215–25. http://dx.doi.org/10.1142/s0217984990001537.

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Thin zirconia (zirconium dioxide) films are deposited by PECVD using as precursors organometallic compounds, metal alkoxides, and metal β-diketonates. The properties of the films depend on the substrate temperature, power density and the nature and partial pressure of the precursor. Thin films of zirconia stabilized with yttria (yttrium oxide) are formed at relatively low deposition temperatures (500°C) using the β-diketones of zirconium and yttrium.

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Ohkubo, Yuji, Takashi Nakagawa, Satoshi Seino, Junichiro Kugai, Takao A. Yamamoto, Hiroaki Nitani, and Yasuhiro Niwa. "X-ray-induced reduction of Au ions in an aqueous solution in the presence of support materials andin situtime-resolved XANES measurements." Journal of Synchrotron Radiation 21, no. 5 (July 31, 2014): 1148–52. http://dx.doi.org/10.1107/s1600577514012703.

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Synchrotron X-ray-induced reduction of Au ions in an aqueous solution with or without support materials is reported. To clarify the process of radiation-induced reduction of metal ions in aqueous solutions in the presence of carbon particles as support materials,in situtime-resolved XANES measurements of Au ions were performed under synchrotron X-ray irradiation. XANES spectra were obtained only when hydrophobic carbon particles were added to the precursor solution containing Au ions. Changes in the shape of the XANES spectra indicated a rapid reduction from ionic to metallic Au in the precursor solution owing to synchrotron X-ray irradiation. In addition, the effects of the wettability of the carbon particles on the deposited Au metallic spots were examined. The deposited Au metallic spots were different depending on the relationship of surface charges between metal precursors and support materials. Moreover, a Au film was obtained as a by-product only when hydrophilic carbon particles were added to the precursor solution containing the Au ions.

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Liu, J., R. Czerw, and D. L. Carroll. "Large-scale synthesis of highly aligned nitrogen doped carbon nanotubes by injection chemical vapor deposition methods." Journal of Materials Research 20, no. 2 (February 2005): 538–43. http://dx.doi.org/10.1557/jmr.2005.0069.

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In this study, we compare the effects of pyridine (C5H5N) and pyrimidine (C4H4N2) precursors, using ferrocene as a metal source, in the production of nitrogen containing multiwalled carbon nanotubes. Using standard chemical vapor deposition techniques, highly aligned mats of carbon-nitrogen carbon nanotube were synthesized. The maximum nitrogen concentration in these materials is between 1% and 2% when pyridine is used as the precursor and can be increased to 3.2% when pyrimidine is used as the precursor. However, the electronic structure of both materials, as determined using scanning tunneling spectroscopy, suggests that the nitrogen is incorporated into the nanotube lattice in the same way for both precursors.

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Keskinen, H., J. M. Mäkelä, M. Vippola, M. Nurminen, J. Liimatainen, T. Lepistö, and J. Keskinen. "Generation of silver/palladium nanoparticles by liquid flame spray." Journal of Materials Research 19, no. 5 (May 2004): 1544–50. http://dx.doi.org/10.1557/jmr.2004.0207.

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Ag–Pd alloy nanoparticles have been generated from silver and palladium nitrate precursors using a high temperature aerosol method, the liquid flame spray (LFS) process. In the LFS process, a spray aerosol of precursor liquid is introduced into a high-temperature H2–O2 flame. The primary micron-sized spray droplets evaporatein the flame, and the final particulate product is a result of the nucleation of the pure metal vapors shortly after the flame. In the study, three Ag–Pd molar ratios—10:90, 50:50, and 90:10—were used in the precursor. As a result of the synthesis, metalalloy nanoparticles with practically the same concentration ratios, correspondingly, were produced with the method. In the experiments, metal mass flow rates of 0.01–0.8 g/min were covered. The size of the particles was determined to be in the rangeof 10–50 nm by aerosol instrumentation. The particles were spherical and slightly agglomerated. It was concluded that the particle size can be controlled via the total precursor mass flow rate, and the composition can be controlled by the molar ratio of Ag and Pd compounds in the precursor liquid.

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Marocco, Antonello, Gianfranco Dell’Agli, Serena Esposito, and Michele Pansini. "Metal-ceramic composite materials from zeolite precursor." Solid State Sciences 14, no. 3 (March 2012): 394–400. http://dx.doi.org/10.1016/j.solidstatesciences.2012.01.006.

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Su, Kai, and Larry G. Sneddon. "A polymer precursor route to metal borides." Chemistry of Materials 5, no. 11 (November 1993): 1659–68. http://dx.doi.org/10.1021/cm00035a013.

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Miklaszewski, Andrzej, and Mieczyslaw Jurczyk. "Mechanical Alloying and Electrical Current-Assisted Sintering Adopted for In Situ Ti-TiB Metal Matrix Composite Processing." Materials 12, no. 4 (February 21, 2019): 653. http://dx.doi.org/10.3390/ma12040653.

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In this work, mechanical alloying and electrical current-assisted sintering was adopted for in situ metal matrix composite material processing. Applied at the initial powder stage, mechanical alloying enables a homogeneous distribution of the starting elements in the proposed precursor powder blends. The accompanying precursor preparation and the structurally confirmed size reduction allow obtainment of a nanoscale range for the objects to be sintered. The nano precursors aggregated in the micro-sized particle objects, subjected to electrical current-assisted sintering, characterize the metal matrix composite sinters with high uniformity, proper densification, and compaction response, as well as maintaining a nanoscale whose occurrence was confirmed by the appearance of the highly dispersed reinforcement phase in the examined Ti-TiB material example. The structural analysis of the sinters confirms the metal matrix composite arrangement and provides an additional quantitive data overview for the comparison of the processing conditions. The mechanical alloying examined in this work and the electrical current-assisted sintering approach allow in situ metal matrix composite structures to create their properties by careful control of the processing steps.

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34

Ndala, Zakhele, Ndivhuwo Shumbula, Siyabonga Nkabinde, Tshwarela Kolokoto, Obakeng Nchoe, Poslet Shumbula, Zikhona N. Tetana, Ella C. Linganiso, Siziwe S. Gqoba, and Nosipho Moloto. "Evaluating the Effect of Varying the Metal Precursor in the Colloidal Synthesis of MoSe2 Nanomaterials and Their Application as Electrodes in the Hydrogen Evolution Reaction." Nanomaterials 10, no. 9 (September 9, 2020): 1786. http://dx.doi.org/10.3390/nano10091786.

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Herein we report on the use of different metal precursors in the synthesis of MoSe2 nanomaterials in order to control their morphology. The use of Mo(CO)6 as the metal precursor resulted in the formation of wrinkled few-layer nanosheets, while the use of H2MoO4 as the metal precursor resulted in the formation of nanoflowers. To investigate the effect of the morphologies on their performance as catalysts in the hydrogen evolution reaction, electrochemical characterization was done using linear sweep voltammetry (LSV), cyclic voltammetry (CV), and electrical impedance spectroscopy (EIS). The MoSe2 nanoflowers were found to have superior electrochemical performance towards the hydrogen evolution reaction with a lower Tafel slope, on-set potential, and overpotential at 10 mA/cm2 compared to the wrinkled few-layer nanosheets. This was found to be due to the higher effective electrochemical surface area of the nanoflowers compared to the nanosheets which suggests a higher number of exposed edge sites in the nanoflowers.

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35

Winiarska, Katarzyna, Roman Klimkiewicz, Włodzimierz Tylus, Agnieszka Sobianowska-Turek, Juliusz Winiarski, Bogdan Szczygieł, and Irena Szczygieł. "Study of the Catalytic Activity and Surface Properties of Manganese-Zinc Ferrite Prepared from Used Batteries." Journal of Chemistry 2019 (January 16, 2019): 1–14. http://dx.doi.org/10.1155/2019/5430904.

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The catalytic activity of the Mn-Zn ferrites obtained by chemical methods from a solution after acid leaching of waste Zn-C and Zn-Mn batteries was studied. Precursors of metal ions (Fe, Mn, and Zn) were obtained using different precipitating agents ((NH4)2C2O4, Na2CO3, and NaOH), and then, the combustion route was used to prepare catalytically active nanocrystalline ferrites. The obtained ferrite catalysts differ in terms of microstructure, the number of acid and base sites, and the surface composition depending on the ion precursor used in the combustion process. All prepared materials were catalytically active in the butan-1-ol conversion test. Depending on the ion precursor applied in the combustion process, a selective catalyst towards aldehyde (carbonate precursor) or ketone (hydroxide precursor) formation can be obtained. Furthermore, the catalyst prepared from the hydroxide precursor exhibits the highest catalytic activity in the n-butanol test (nearly 100% conversion under the experiment conditions).

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36

Žumbar, Tadej, Alenka Ristić, Goran Dražić, Hristina Lazarova, Janez Volavšek, Albin Pintar, Nataša Zabukovec Logar, and Nataša Novak Tušar. "Influence of Alumina Precursor Properties on Cu-Fe Alumina Supported Catalysts for Total Toluene Oxidation as a Model Volatile Organic Air Pollutant." Catalysts 11, no. 2 (February 13, 2021): 252. http://dx.doi.org/10.3390/catal11020252.

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The structure–property relationship of catalytic supports for the deposition of redox-active transition metals is of great importance for improving the catalytic efficiency and reusability of the catalysts. In this work, the role of alumina support precursors of Cu-Fe/Al2O3 catalysts used for the total oxidation of toluene as a model volatile organic air pollutant is elucidated. Surface characterization of the catalysts revealed that the surface area, pore volume and acid site concentration of the alumina supports are important but not the determining factors for the catalytic activity of the studied catalysts for this type of reaction. The determining factors are the structural order of the support precursor, the homogeneous distribution of the catalytic sites and reducibility, which were elucidated by XRD, NMR, TEM and temperature programed reduction (TPR). Cu–Fe/Al2O3 prepared from bayerite and pseudoboehmite as highly ordered precursors showed better catalytic performance compared to Cu-Fe/Al2O3 derived from the amorphous alumina precursor and dawsonite. Homogeneous distribution of FexOy and CuOx with defined Cu/Fe molar ratio on the Al2O3 support is required for the efficient catalytic performance of the material. The study showed a beneficial effect of low iron concentration introduced into the alumina precursor during the alumina support synthesis procedure, which resulted in a homogeneous metal oxide distribution on the support.

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Shimizu, Toru. "Preparation of TiAl Intermetallic Alloy Precursor Using Slow Reaction Synthesis Process." Materials Science Forum 941 (December 2018): 1312–17. http://dx.doi.org/10.4028/www.scientific.net/msf.941.1312.

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Already, there are several processes to produce intermetalic alloy parts from powder , ex. metal injection molding (MIM) or additive manufacturing (AM). For these processes, pre-alloyed powder made by gas atomized powder is used because of their quality. As other way, intermetallic alloy can be produced combustion reaction process. On this process, ingredient metal powders are mixed and reacted by combustion. However, powders are fused by reaction heat, and they are difficult to keep the powder condition. There for, we are developed the process to produce intermetallic alloy precursor by slow combustion reaction. On this process, temperature of mixed powders increases slower than 0.2K/sec. while the combustion reaction, and powders are reacted without fusing. Using this process, TiAl presursor is synthesized. Relation of reacting condition and quality of the precursor is evaluated, and researched the practical usage of this precurser.

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38

Iudicello, Antonella, Stefano Boschi, Pietro Ghedini, Frank Lohr, and Stefano Panareo. "Optimization of Precursor Preparation in PSMA-11 Radiolabeling to Obtain a Highly Reproducible Radiochemical Yield." Pharmaceuticals 15, no. 3 (March 11, 2022): 343. http://dx.doi.org/10.3390/ph15030343.

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[68Ga]Ga-PSMA-11 PET/CT plays a pivotal role in the diagnosis and staging of prostate cancer because of its higher sensitivity and detection rate compared with traditional choline PET/CT. A highly reproducible radiochemical yield of the radiopharmaceutical to be used in the clinical routine is an important parameter for planning and optimization of clinical activity. During radiometallation of PSMA-11, the presence of metal ion contaminants in the peptide precursor may cause a decrease in the [68Ga]Ga-PSMA-11 radiochemical yield because of metal ion contaminants competition with gallium-68. To optimize the radiochemical yield of [68Ga]Ga-PSMA-11 radiosynthesis, data obtained by preparing the solution of the PSMA-11 precursor with three different methods (A, B, and C) were compared. Methods A and B consisted of the reconstitution of different quantities of precursor (1000 µg and 30 µg, respectively) to obtain a 1 µg/mL solution. In Method A, the precursor solution was aliquoted and stored frozen, while the precursor solution obtained with Method B was entirely used. Method C consisted of the reconstitution of 1000 µg of precursor taking into account net peptide content as described in European Pharmacopoeia. Radiosynthesis data demonstrated that reconstitution methods B and C gave a consistently higher and reproducible radiochemical yield, highlighting the role of metals and precursor storage conditions on the synthesis performance.

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Daniels, Zachary, Wilson Rydalch, Troy Y. Ansell, Claudia C. Luhrs, and Jonathan Phillips. "Reduction Expansion Synthesis of Sintered Metal." Materials 12, no. 18 (September 6, 2019): 2890. http://dx.doi.org/10.3390/ma12182890.

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Described herein is a novel method, Reduction Expansion Synthesis-Sintered Metal (RES-SM), to create a sintered metal body of a designed shape at ambient pressure, hundreds of degrees below the metal melting temperature. The precursor to the metal part is a mixture of metal oxide particles and activated metal particles, and in this study specifically nickel oxide and activated nickel metal particles. It is postulated that the metal oxide component is reduced via exposure to chemical radical species produced via thermal decomposition of urea or other organic compounds. In the study performed, the highest temperature required was 950 °C, the longest duration of high temperature treatment was 1200 s, and in all cases, the atmosphere was inert gas at ambient pressure. As discovered using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and x-ray diffraction (XRD), the metal that forms via the RES process presents necks of completely reduced metal between existing metal particles. The ‘as produced’ parts are similar in properties to ‘brown’ metal parts created using more standard methods and require ‘post processing’ to full densify. Parts treated by hot isostatic pressing show fully self-supporting, robust structures, with hardness values like others reported in literature for traditional fabrication methods. This novel method uses affordable and environmentally friendly precursors to join metallic parts at moderate temperatures, produces fully reduced metals in a very short time and has potential to make many parts simultaneously in a standard laboratory furnace.

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Zhang, Chi, Haiyan Wang, Yanmei Nie, Weidong Yu, and Jun Yan. "MOF-derived Co3O4 microspheres with pagoda cauliflower shape as anode materials for stable life Li-ion battery." Functional Materials Letters 13, no. 06 (July 31, 2020): 2050029. http://dx.doi.org/10.1142/s1793604720500290.

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Metal organic frameworks (MOFs) are widely used in the synthesis of metal oxides as important organic–inorganic compound precursors. A perovskite ABO3-type Co-based MOF [NH4][Co(HCOO)3] was synthesized from a simple mixture without any adjuvant. Porous Co3O4 microspheres are used as anode materials for lithium-ion batteries (LIBs), which are obtained from [NH4][Co(HCOO)3] as a precursor through a pyrolysis process in air. The obtained pagoda cauliflower-shaped Co3O4 microspheres exhibit an excellent electrochemical performance.

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41

Kim, Yujin, Kwangmo Yang, and Seonghoon Lee. "Highly luminescent blue-emitting In1−xGaxP@ZnS quantum dots and their applications in QLEDs with inverted structure." Journal of Materials Chemistry C 8, no. 23 (2020): 7679–87. http://dx.doi.org/10.1039/c8tc06629a.

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A novel P precursor with controllable reactivity and new metal complex precursors soluble in ODE are created and used for blue-emitting In_1−xGa_xP@ZnS QDs (PLQY: 65%; FWHM: 46 nm). The III–V-CQD based blue-QLED of the best EQE until now is reported.

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42

Zhang, Ya Hui, Xi Cheng, and Qing Wang. "A Low Temperature Precursor Sulfuration Route to Metal Sulfides Nanomaterials." Advanced Materials Research 148-149 (October 2010): 1404–7. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.1404.

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A low-temperature precursor sulfuration route has been established to prepare metal sulfides with different nanostructures during the synthesis of nickel sulfide. The advantages of the low-temperature precursor sulfuration route were testified by the synthesis of different metal sulfides ( lead sulfide, zinc sulfide and cobalt sulfide). It offers a novel path to the preparation of other metal sulfides.

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Sharma, Geetu, and P. Jeevanandam. "Synthesis of Transition Metal Oxide Based MgO Nanocomposites by a Simple Precursor Approach." Advanced Materials Research 585 (November 2012): 169–73. http://dx.doi.org/10.4028/www.scientific.net/amr.585.169.

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MgO based nanocomposites possess a wide range of applications in various catalytic reactions. Transition metal oxide based MgO nanocomposites are expected to be useful in spintronics. MgO has been chosen due to its less interaction with magnetic nanoparticles and also it provides stability to the magnetic nanoparticles. In the present study, MgO–Co3O4and MgO–NiO nanocomposites have been synthesized by a simple precursor approach. Firstly, magnesium oxychloride precursors were prepared using aqueous solutions of magnesium chloride, cobalt chloride (or nickel chloride) and nanocrystalline MgO which on calcination at 500°C led to MgO–Co3O4and MgO–NiO nanocomposites. The nanocomposites were characterized by XRD, FE-SEM, EDXA, TEM and magnetic measurements. The XRD results indicate the formation of Co3O4and NiO along with MgO on calcination of the precursors. The SEM and TEM images indicate the presence of MgO particles along with transition metal oxide nanoparticles. Magnetic measurements of both the nanocomposites (M-H) indicate superparamagnetic behavior at 5 K.

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Pham, Thien Huu, Ha An Quoc Than, and Ha Manh Bui. "The catalytic oxidation of toluene at low temperature over palladium nanoparticles supported on Alumina sphere catalysts: effects of Palladium precursors and preparation method." Polish Journal of Chemical Technology 21, no. 4 (December 1, 2019): 48–50. http://dx.doi.org/10.2478/pjct-2019-0038.

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Abstract In this study, 1 wt.% Pd/Al2O3 sphere catalysts were prepared using the wet-impregnation (WI) and deposition-precipitation (DP) method using palladium chloride and tetraamminepalladium (II) nitrate as salt precursors. All catalysts were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier-transform infrared (FTIR) spectroscopy. The catalytic activity in toluene oxidation under gas-phase conditions was measured. The obtained results showed that metal dispersion and catalytic activity were strongly dependent on the salt precursor and method of catalyst preparation. The use of tetraamminepalladium (II) nitrate as the precursor presented smaller particle size, an enhanced dispersion and higher specific surface area. Moreover, the catalyst prepared with this precursor also showed higher catalytic activity than that prepared with palladium chloride. At 1 wt.% Pd loading, complete oxidation of toluene was achieved at 250°C. However, there was only approximately 80–90% efficient at the same temperature when the catalyst was prepared with palladium chloride as the precursor.

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45

Na, Kyeong-Han, Wan-Tae Kim, Tae-Hyeob Song, Sung-Wook Kim, and Won-Youl Choi. "Microstructure of Ni0.5Zn0.5Fe2O4 Nanofiber with Metal Nitrates in Electrospinning Precursor." Nanomaterials 10, no. 7 (July 9, 2020): 1344. http://dx.doi.org/10.3390/nano10071344.

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Electrospun NiZn ferrite nanofibers have great potential due to their one-dimensional structure and electrical properties, but they have a low reproducibility resulting from many process confounders, so much research effort is needed to achieve optimized process control. For structure control, the viscosity of the precursor solution is a likely parameter. One solution is to use polyvinyl pyrrolidone (PVP) and metal nitrate to obtain the desired viscosity by increasing the nitrate content, even if the polymer content is decreased. Ni0.5Zn0.5Fe2O4 ferrite nanofiber was electrospun with various precursor conditions. Fifteen different precursor solutions, with a content of five polymers and three metal nitrates, were prepared, with precursor solutions composed of Fe(NO3)2·9H2O, Ni(NO3)2·6H2O, Zn(NO3)2·6H2O, polyvinyl pyrrolidone (PVP), and N,N-dimethylmethanamide. The fiber diameter changed from the lowest, of 62.41 nm, to 417.54 nm. This study shows that the average diameter can be controlled using the metal nitrate concentration without a difference in crystal structure when PVP is used. In a 24.0 mmol metal nitrate precursor solution, the process yield was improved to 140% after heat treatment. There was also no significant difference in the crystal structure and morphology. This system reduces the cost of raw materials for electrospinning and increases the process yield of NiZn ferrite nanofibers.

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Mamonova, Daria V., Anna A. Vasileva, Yuri V. Petrov, Alexandra V. Koroleva, Denis V. Danilov, Ilya E. Kolesnikov, Gulia I. Bikbaeva, Julien Bachmann, and Alina A. Manshina. "Single Step Laser-Induced Deposition of Plasmonic Au, Ag, Pt Mono-, Bi- and Tri-Metallic Nanoparticles." Nanomaterials 12, no. 1 (December 31, 2021): 146. http://dx.doi.org/10.3390/nano12010146.

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Multimetallic plasmonic systems usually have distinct advantages over monometallic nanoparticles due to the peculiarity of the electronic structure appearing in advanced functionality systems, which is of great importance in a variety of applications including catalysis and sensing. Despite several reported techniques, the controllable synthesis of multimetallic plasmonic nanoparticles in soft conditions is still a challenge. Here, mono-, bi- and tri-metallic nanoparticles were successfully obtained as a result of a single step laser-induced deposition approach from monometallic commercially available precursors. The process of nanoparticles formation is starting with photodecomposition of the metal precursor resulting in nucleation and the following growth of the metal phase. The deposited nanoparticles were studied comprehensively with various experimental techniques such as SEM, TEM, EDX, XPS, and UV-VIS absorption spectroscopy. The size of monometallic nanoparticles is strongly dependent on the type of metal: 140–200 nm for Au, 40–60 nm for Ag, 2–3 nm for Pt. Bi- and trimetallic nanoparticles were core-shell structures representing monometallic crystallites surrounded by an alloy of respective metals. The formation of an alloy phase took place between monometallic nanocrystallites of different metals in course of their growth and agglomeration stage.

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Müller, J. E. "Model of anH2-Precursor State on Metal Surfaces." Physical Review Letters 59, no. 26 (December 28, 1987): 2943–46. http://dx.doi.org/10.1103/physrevlett.59.2943.

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48

Forsgren, K., and A. Hårsta. "CVD of ZrO2 using ZrI4 as metal precursor." Le Journal de Physique IV 09, PR8 (September 1999): Pr8–487—Pr8–491. http://dx.doi.org/10.1051/jp4:1999861.

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49

Kim, Dongsoo, and Choljin Choi. "Laser-Induced Metal Reduction from Liquid Electrolyte Precursor." Journal of Nanoscience and Nanotechnology 13, no. 11 (November 1, 2013): 7581–85. http://dx.doi.org/10.1166/jnn.2013.7885.

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50

Schulz, Douglas L., Robert A. Sailer, Scott Payne, James Leach, and Ronald J. Molz. "Thin films by metal-organic precursor plasma spray." Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films 27, no. 4 (July 2009): 962–69. http://dx.doi.org/10.1116/1.3148826.

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Journal articles on the topic 'Metal precursor'

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