Articoli di riviste: "Oxydes 2D"

1

Yin, Hongfei, Chunyu Yuan, Huijun Lv, Xulin He, Cheng Liao, Xiaoheng Liu e Yongzheng Zhang. "Construction of Electrostatic Self-Assembled 2D/2D CdIn2S4/g-C3N4 Heterojunctions for Efficient Visible-Light-Responsive Molecular Oxygen Activation". Nanomaterials 11, n. 9 (9 settembre 2021): 2342. http://dx.doi.org/10.3390/nano11092342.

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Molecular oxygen activated by visible light to generate radicals with high oxidation ability exhibits great potential in environmental remediation The efficacy of molecular oxygen activation mainly depends on the separation and migration efficiency of the photoinduced charge carriers. In this work, 2D/2D CdIn2S4/g-C3N4 heterojunctions with different weight ratios were successfully fabricated by a simple electrostatic self-assembled route. The optimized sample with a weight ratio of 5:2 between CdIn2S4 and g-C3N4 showed the highest photocatalytic activity for tetracycline hydrochloride (TCH) degradation, which also displayed good photostability. The enhancement of the photocatalytic performance could be ascribed to the 2D/2D heterostructure; this unique 2D/2D structure could promote the separation and migration of the photoinduced charge carriers, which was beneficial for molecular oxygen activation, leading to an enhancement in photocatalytic activity. This work may possibly provide a scalable way for molecular oxygen activation in photocatalysis.

2

Rowley-Neale, Samuel J., Jamie M. Fearn, Dale A. C. Brownson, Graham C. Smith, Xiaobo Ji e Craig E. Banks. "2D molybdenum disulphide (2D-MoS2) modified electrodes explored towards the oxygen reduction reaction". Nanoscale 8, n. 31 (2016): 14767–77. http://dx.doi.org/10.1039/c6nr04073j.

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Jian, Jiaying, Honglong Chang, Pengfan Dong, Zewen Bai e Kangnian Zuo. "A mechanism for the variation in the photoelectric performance of a photodetector based on CVD-grown 2D MoS2". RSC Advances 11, n. 9 (2021): 5204–17. http://dx.doi.org/10.1039/d0ra10302k.

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The CVD-grown 2D MoS₂ is the oxygen-doped MoS₂. Annealing treatment can increase the O-doping concentration in the CVD-grown 2D MoS₂ while vulcanization can make the CVD-grown 2D MoS₂ transition from the an oxygen-doped state to the a pure state.

4

Ozturk, Birol, Andres de-Luna-Bugallo, Eugen Panaitescu, Ann N. Chiaramonti, Fangze Liu, Anthony Vargas, Xueping Jiang et al. "Atomically thin layers of B–N–C–O with tunable composition". Science Advances 1, n. 6 (luglio 2015): e1500094. http://dx.doi.org/10.1126/sciadv.1500094.

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In recent times, atomically thin alloys of boron, nitrogen, and carbon have generated significant excitement as a composition-tunable two-dimensional (2D) material that demonstrates rich physics as well as application potentials. The possibility of tunably incorporating oxygen, a group VI element, into the honeycomb sp2-type 2D-BNC lattice is an intriguing idea from both fundamental and applied perspectives. We present the first report on an atomically thin quaternary alloy of boron, nitrogen, carbon, and oxygen (2D-BNCO). Our experiments suggest, and density functional theory (DFT) calculations corroborate, stable configurations of a honeycomb 2D-BNCO lattice. We observe micrometer-scale 2D-BNCO domains within a graphene-rich 2D-BNC matrix, and are able to control the area coverage and relative composition of these domains by varying the oxygen content in the growth setup. Macroscopic samples comprising 2D-BNCO domains in a graphene-rich 2D-BNC matrix show graphene-like gate-modulated electronic transport with mobility exceeding 500 cm2 V−1 s−1, and Arrhenius-like activated temperature dependence. Spin-polarized DFT calculations for nanoscale 2D-BNCO patches predict magnetic ground states originating from the B atoms closest to the O atoms and sizable (0.6 eV < Eg < 0.8 eV) band gaps in their density of states. These results suggest that 2D-BNCO with novel electronic and magnetic properties have great potential for nanoelectronics and spintronic applications in an atomically thin platform.

5

Waheed, Abdul, Sadaf Siddique, Mutawara Mahmood Baig, Muhammad Taqi Mehran, Muhammad Iftikhar, Jamil Ahmad, Hassan A. Arafat e Faisal Shahzad. "2D/2D interfacial coupling of NiFe-LDH and Ti3C2T for oxygen evolution reaction". International Journal of Hydrogen Energy 72 (giugno 2024): 133–40. http://dx.doi.org/10.1016/j.ijhydene.2024.05.367.

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6

Fang, Hengyi, Taizhong Huang, Dong Liang, Ming Qiu, Yue Sun, Shuo Yao, Jiemei Yu et al. "Prussian blue analog-derived 2D ultrathin CoFe2O4 nanosheets as high-activity electrocatalysts for the oxygen evolution reaction in alkaline and neutral media". Journal of Materials Chemistry A 7, n. 13 (2019): 7328–32. http://dx.doi.org/10.1039/c9ta00640k.

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7

Je, Minyeong, Eun Seob Sim, Jungwook Woo, Heechae Choi e Yong-Chae Chung. "Manipulatable Interface Electric Field and Charge Transfer in a 2D/2D Heterojunction Photocatalyst via Oxygen Intercalation". Catalysts 10, n. 5 (25 aprile 2020): 469. http://dx.doi.org/10.3390/catal10050469.

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Charge separation is the most important factor in determining the photocatalytic activity of a 2D/2D heterostructure. Despite the exclusive advantages of 2D/2D heterostructure semiconductor systems such as large surface/volume ratios, their use in photocatalysis is limited due to the low efficiency of charge separation and high recombination rates. As a remedy for the weak interlayer binding and low carrier transport efficiency in 2D/2D heterojunctioned semiconductors, we suggested an impurity intercalation method for the 2D/2D interface. PtS2/C3N4, as a prototype heterojunction material, was employed to investigate the effect of anion intercalation on the charge separation efficiency in a 2D/2D system using density functional theory. With oxygen intercalation at the PtS2/C3N4 interface, a reversed and stronger localized dipole moment and a built-in electric field were induced in the vertical direction of the PtS2/C3N4 interface. This theoretical work suggests that the anion intercalation method can be a way to control built-in electric fields and charge separation in designs of 2D/2D heterostructures that have high photocatalytic activity.

8

Xu, Hanwen, Jiawei Zhu, Qianli Ma, Jingjing Ma, Huawei Bai, Lei Chen e Shichun Mu. "Two-Dimensional MoS2: Structural Properties, Synthesis Methods, and Regulation Strategies toward Oxygen Reduction". Micromachines 12, n. 3 (27 febbraio 2021): 240. http://dx.doi.org/10.3390/mi12030240.

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Compared with three-dimensional (3D) and other materials, two-dimensional (2D) materials with unique properties such as high specific surface area, structurally adjustable band structure, and electromagnetic properties have attracted wide attention. In recent years, great progress has been made for 2D MoS2 in the field of electrocatalysis, and its exposed unsaturated edges are considered to be active sites of electrocatalytic reactions. In this review, we focus on the latest progress of 2D MoS2 in the oxygen reduction reaction (ORR) that has not received much attention. First, the basic properties of 2D MoS2 and its advantages in the ORR are introduced. Then, the synthesis methods of 2D MoS2 are summarized, and specific strategies for optimizing the performance of 2D MoS2 in ORRs, and the challenges and opportunities faced are discussed. Finally, the future of the 2D MoS2-based ORR catalysts is explored.

9

Gao, Ge, Kang Wang e Xitao Wang. "2D/2D core/shell structure of FeCo2O4@NiMn LDH for efficient oxygen evolution reaction". Journal of Alloys and Compounds 937 (marzo 2023): 168478. http://dx.doi.org/10.1016/j.jallcom.2022.168478.

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10

Yang, Xiaohang, Zhen Feng e Zhanyong Guo. "Theoretical Investigation on the Hydrogen Evolution, Oxygen Evolution, and Oxygen Reduction Reactions Performances of Two-Dimensional Metal-Organic Frameworks Fe3(C2X)12 (X = NH, O, S)". Molecules 27, n. 5 (24 febbraio 2022): 1528. http://dx.doi.org/10.3390/molecules27051528.

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Two-dimensional metal-organic frameworks (2D MOFs) inherently consisting of metal entities and ligands are promising single-atom catalysts (SACs) for electrocatalytic chemical reactions. Three 2D Fe-MOFs with NH, O, and S ligands were designed using density functional theory calculations, and their feasibility as SACs for hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) was investigated. The NH, O, and S ligands can be used to control electronic structures and catalysis performance in 2D Fe-MOF monolayers by tuning charge redistribution. The results confirm the Sabatier principle, which states that an ideal catalyst should provide reasonable adsorption energies for all reaction species. The 2D Fe-MOF nanomaterials may render highly-efficient HER, OER, and ORR by tuning the ligands. Therefore, we believe that this study will serve as a guide for developing of 2D MOF-based SACs for water splitting, fuel cells, and metal-air batteries.

11

Khan, Aamar F., Alejandro Garcia-Miranda Ferrari, Jack P. Hughes, Graham C. Smith, Craig E. Banks e Samuel J. Rowley-Neale. "2D-Hexagonal Boron Nitride Screen-Printed Bulk-Modified Electrochemical Platforms Explored towards Oxygen Reduction Reactions". Sensors 22, n. 9 (26 aprile 2022): 3330. http://dx.doi.org/10.3390/s22093330.

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A low-cost, scalable and reproducible approach for the mass production of screen-printed electrode (SPE) platforms that have varying percentage mass incorporations of 2D hexagonal boron nitride (2D-hBN) (2D-hBN/SPEs) is demonstrated herein. These novel 2D-hBN/SPEs are explored as a potential metal-free electrocatalysts towards oxygen reduction reactions (ORRs) within acidic media where their performance is evaluated. A 5% mass incorporation of 2D-hBN into the SPEs resulted in the most beneficial ORR catalysis, reducing the ORR onset potential by ca. 200 mV in comparison to bare/unmodified SPEs. Furthermore, an increase in the achievable current of 83% is also exhibited upon the utilisation of a 2D-hBN/SPE in comparison to its unmodified equivalent. The screen-printed fabrication approach replaces the less-reproducible and time-consuming drop-casting technique of 2D-hBN and provides an alternative approach for the large-scale manufacture of novel electrode platforms that can be utilised in a variety of applications.

12

Khan, Aamar F., Michael P. Down, Graham C. Smith, Christopher W. Foster e Craig E. Banks. "Surfactant-exfoliated 2D hexagonal boron nitride (2D-hBN): role of surfactant upon the electrochemical reduction of oxygen and capacitance applications". Journal of Materials Chemistry A 5, n. 8 (2017): 4103–13. http://dx.doi.org/10.1039/c6ta09999h.

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Surfactant-exfoliated 2D hexagonal boron nitride (2D-hBN) nanosheets are fabricated using the surfactant sodium cholate in aqueous media and are explored towards the electrochemical reduction of oxygen.

13

Putri, Lutfi Kurnianditia, Boon-Junn Ng, Wee-Jun Ong, Hing Wah Lee, Wei Sea Chang e Siang-Piao Chai. "Engineering nanoscale p–n junction via the synergetic dual-doping of p-type boron-doped graphene hybridized with n-type oxygen-doped carbon nitride for enhanced photocatalytic hydrogen evolution". Journal of Materials Chemistry A 6, n. 7 (2018): 3181–94. http://dx.doi.org/10.1039/c7ta09723a.

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14

Jin, Lei, Nerea Bilbao, Yang Lv, Xiao-Ye Wang, Paniz Soltani, Kunal S. Mali, Akimitsu Narita, Steven De Feyter, Klaus Müllen e Zongping Chen. "2D self-assembly and electronic characterization of oxygen–boron–oxygen-doped chiral graphene nanoribbons". Chemical Communications 57, n. 49 (2021): 6031–34. http://dx.doi.org/10.1039/d1cc01901e.

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15

Jung, In-Sun, Hyuk Jae Kwon, Mokwon Kim, Doyoung Kim, Jung-Hwa Kim, Hyangsook Lee, Dongjin Yun et al. "Rapid oxygen diffusive lithium–oxygen batteries using a restacking-inhibited, free-standing graphene cathode film". Journal of Materials Chemistry A 7, n. 17 (2019): 10397–404. http://dx.doi.org/10.1039/c9ta00320g.

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16

Li, Yongxiang, Salvatore Gianluca Leonardi, Anna Bonavita, Giovanni Neri e Wojtek Wlodarski. "Two-Dimensional (2D) SnS 2 -based Oxygen Sensor". Procedia Engineering 168 (2016): 1102–5. http://dx.doi.org/10.1016/j.proeng.2016.11.355.

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17

Lin, Li, Xing Du, Junjie Wang, Hui Chen, Xuan He, Wei Fang, Yang Li, Zhen Chen e Lei Zhao. "High-pressure vapor-solid transformation of 2D template to derive 2D Co–N–C electrocatalysts for oxygen reduction reaction". Nanotechnology 33, n. 10 (13 dicembre 2021): 105601. http://dx.doi.org/10.1088/1361-6528/ac3d64.

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Abstract Two-dimensional (2D) cobalt zeolitic imidazolate frameworks (ZIF-67) have attracted significant research interests to synthesize cobalt and nitrogen co-doped carbon-based (Co–N–C) catalyst for oxygen reduction reaction (ORR). However, most of the current synthetic approaches of 2D ZIF-67 are energy-intensive, environmentally hazardous and low-yield. Herein, a feasible and efficient ‘morphology-retaining method via a high-pressure vapor-solid reaction’ are reported to synthesize 2D ZIF-67 nanosheets by using 2D cobalt carbonate hydroxide template. In the strategy, the high-pressure vapor caused by sublimation of 2-Melm and the pores formed from effusion of CO2 during transformation ensure the complete transformation from 2D template to 2D ZIF-67. The corresponding 2D Co–N–C catalyst exhibits comparable ORR electrocatalytic activity and better stability than Pt/C in alkaline media. The present method is expected to offer a feasible and universal way to efficiently synthesize 2D M–N–C catalysts.

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Ma, Yuhao, Dingxin Xu, Weirui Chen, Yiming Tang, Xi Wang, Laisheng Li e Jing Wang. "Oxygen-vacancy-embedded 2D/2D NiFe-LDH/MXene Schottky heterojunction for boosted photodegradation of norfloxacin". Applied Surface Science 572 (gennaio 2022): 151432. http://dx.doi.org/10.1016/j.apsusc.2021.151432.

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19

Wang, Huihu, Hao Tu, Haiping Hu, Yuan Chen, Pascal Boulet e Marie-Christine Record. "Construction of 2D/2D g-C3N4/CeO2 heterostructure and its oxygen vacancy mediated photocatalytic activity". Materials Letters 336 (aprile 2023): 133899. http://dx.doi.org/10.1016/j.matlet.2023.133899.

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20

Hubbard Cristinacce, Penny L., Minal Patel, Alexander Oh, Josephine H. Naish, Edward D. Johnstone e Emma Ingram. "Comparison of 2D and 3D oxygen-enhanced MRI of the placenta". PLOS ONE 19, n. 5 (22 maggio 2024): e0302623. http://dx.doi.org/10.1371/journal.pone.0302623.

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Oxygen-Enhanced Magnetic Resonance Imaging (OE-MRI) of the human placenta is potentially a sensitive marker of in vivo oxygenation. This methodological study shows that full coverage of the placenta is possible using 3D mapping of the change in longitudinal relaxation rate (ΔR1), in a group of healthy pregnant subjects breathing elevated levels of oxygen. Twelve pregnant subjects underwent a comparison of 2D and 3D OE-MRI. ΔR1 was mapped for a single 2D slice (ss-2D), a single matched-slice from the 3D volume (ss-3D) and the full 3D volume (vol-3D). The group-average median ΔR1 values for ss-3D (0.023 s-1) and vol-3D (0.022 s-1) do not differ significantly from ss-2D (0.020 s-1), when compared using a two-tailed paired t-test (ss-3D (p = 0.58) and vol-3D (p = 0.70)). However, median baseline T1 (T1b) for ss-2D was higher (1603 ms) than T1b for ss-3D (1540 ms, p = 0.07) and significantly higher than vol-3D (1515 ms, p = 0.02), when compared using a two-tailed paired t-test. In contrast with previous studies, no correlation of median ΔR1 with gestation age at scan for the normal group (N = 10) was observed for ss-2D, likely due to the smaller gestational range. Full volume OE-MRI maps reveal sensitivity to changes in ΔR1, with some participants showing an enhanced gradient in the intermediate space between the fetal and maternal sides of the placenta in the 3D data. This study shows that it is feasible to acquire whole placental volume OE-MRI data in women with healthy pregnancy.

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Basyooni-M. Kabatas, Mohamed A. "A Comprehensive Review on Electrocatalytic Applications of 2D Metallenes". Nanomaterials 13, n. 22 (17 novembre 2023): 2966. http://dx.doi.org/10.3390/nano13222966.

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This review introduces metallenes, a cutting-edge form of atomically thin two-dimensional (2D) metals, gaining attention in energy and catalysis. Their unique physicochemical and electronic properties make them promising for applications like catalysis. Metallenes stand out due to their abundance of under-coordinated metal atoms, enhancing the catalytic potential by improving atomic utilization and intrinsic activity. This review explores the utility of 2D metals as electrocatalysts in sustainable energy conversion, focusing on the Oxygen Evolution Reaction, Oxygen Reduction Reaction, Fuel Oxidation Reaction, and Carbon Dioxide Reduction Reaction. Aimed at researchers in nanomaterials and energy, the review is a comprehensive resource for unlocking the potential of 2D metals in creating a sustainable energy landscape.

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Shtepliuk, Ivan. "Defect-Induced Modulation of a 2D ZnO/Graphene Heterostructure: Exploring Structural and Electronic Transformations". Applied Sciences 13, n. 12 (17 giugno 2023): 7243. http://dx.doi.org/10.3390/app13127243.

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This paper presents a theoretical study on the effects of selected defects (oxygen vacancies and substitutional FeZn atoms) on the structural and electronic properties of a 2D ZnO/graphene heterostructure. Spin-polarized Hubbard- and dispersion-corrected density functional theory (DFT) was used to optimize the geometrical configurations of the heterostructure and to analyze the equilibrium distance, interlayer distance, adhesion energy, and bond lengths. Charge density difference (CDD) analysis and band structure calculations were also performed to study the electronic properties of the heterostructure. The results show that the presence of defects affects the interlayer distance and adhesion energy, with structures including oxygen vacancies and FeZn substitutional atoms having the strongest interaction with graphene. It is demonstrated that the oxygen vacancies generate localized defect states in the ZnO bandgap and lead to a shift of both valence and conduction band positions, affecting the Schottky barrier. In contrast, Fe dopants induce strong spin polarization and high spin density localized on Fe atoms and their adjacent oxygen neighbors as well as the spin asymmetry of Schottky barriers in 2D ZnO/graphene. This study presents a comprehensive investigation into the effects of graphene on the electronic and adsorption properties of 2D ZnO/graphene heterostructures. The changes in electronic properties induced by oxygen vacancies and Fe dopants can enhance the sensitivity and catalytic activity of the 2D ZnO/graphene system, making it a promising material for sensing and catalytic applications.

23

Li, Jia-Hui, Jie Wu e Yang-Xin Yu. "Singlet oxygen vs. triplet oxygen: functions of 2D-MoO3 catalysts in conquering catastrophic parasitic-reactions in lithium– and sodium–oxygen batteries". Journal of Materials Chemistry A 9, n. 16 (2021): 10186–98. http://dx.doi.org/10.1039/d1ta00699a.

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A 2D-MoO₃ nanosheet was predicted both thermodynamically and kinetically to have functionalities to prevent singlet oxygen formation and thus increase the specific energy and cycling performance of Li– and Na–O₂ cells.

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Vasilyev, V., A. M. Amarsi, H. G. Ludwig e B. Lemasle. "Two-dimensional non-LTE O I 777 nm line formation in radiation hydrodynamics simulations of Cepheid atmospheres". Astronomy & Astrophysics 624 (aprile 2019): A85. http://dx.doi.org/10.1051/0004-6361/201935067.

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Oxygen abundance measurements are important for understanding stellar structure and evolution. Measured in Cepheids, they further provide clues on the metallicity gradient and chemo-dynamical evolution in the Galaxy. However, most of the abundance analyses of Cepheids to date have been based on one-dimensional (1D) hydrostatic model atmospheres. Here, we test the validity of this approach for the key oxygen abundance diagnostic, the O I 777 nm triplet lines. We carry out two-dimensional (2D) non-LTE radiative transfer calculations across two different 2D radiation hydrodynamics simulations of Cepheid atmospheres, having stellar parameters of Teff = 5600 K, solar chemical compositions, and log g = 1.5 and 2.0, corresponding to pulsation periods of 9 and 3 days, respectively. We find that the 2D non-LTE versus 1D LTE abundance differences range from −1.0 to −0.25 dex depending on pulsational phase. The 2D non-LTE versus 1D non-LTE abundance differences range from −0.2 to 0.8 dex. The abundance differences are smallest when the Cepheid atmospheres are closest to hydrostatic equilibrium, corresponding to phases of around 0.3–0.8, and we recommend these phases for observers deriving the oxygen abundance from O I 777 nm triplet with 1D hydrostatic models.

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Çeçen, F., e I. E. Gönenç. "Nitrogen removal characteristics of nitrification and denitrification filters". Water Science and Technology 29, n. 10-11 (1 ottobre 1994): 409–16. http://dx.doi.org/10.2166/wst.1994.0786.

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The kinetics of nitrogen removal was studied in upflow submerged nitrification and denitrification filters in series. Nitrification followed first-, half-, and zero-order kinetics. For the half-order range the half-order rate constant was about 0.9gNH4-N1/2m−1/2d−1. The zero-order rate constants for the DO ranges of 2-3 mg/L and 4-5 mg/L were found as 0.47 gNH4-Nm−2d−1 and 1.82 gNH4-Nm−2d−1, respectively. In the zero-order region ammonia removal proceeded as a half-order reaction in oxygen concentration and the half-order rate constants were about 1.4-2.7 gO21/2m−1/2d−1. Nitrite accumulation reached a considerable degree at bulk oxygen to bulk ammonia ratios lower than 5 since the formation of nitrate was inhibited. Similar to nitrification half- and zero-order kinetic regions were also observed in denitrification. The half- and zero-order rate constants for carbon unlimited cases (influent COD/NOx-N>5) were about 0.23 gNOx-N1/2m−1/2d−1 and 1.9 gNOx-Nm−2d−1, respectively. The nitrite produced in the nitrification stage could be reduced in denitrification. The removal kinetics in the presence of nitrite was found to be similar to the kinetics when the influent consisted of nitrate only.

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MATAKUPAN, RUDY WOLTER. "PENDEKATAN SISTEM 2D MODEL STREETER-PHELPS UNTUK MODEL POLUSI SUNGAI". BAREKENG: Jurnal Ilmu Matematika dan Terapan 5, n. 1 (1 marzo 2011): 1–8. http://dx.doi.org/10.30598/barekengvol5iss1pp1-8.

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Applications to positive 2D system can follow Steeter-Phelps model to river flow model. bymodifying the discrete values. mathematical model structure provided by the river flow at timestep t is proportional to the length of rivers and water velocity. The variables that influence isDissolved oxygen (DO) and Biological oxygen demand (BOD), both these variables arecalculated by balance considerations equetion with the screening process, the process ofreaeration, and the source of BOD established a mathematical model of positive 2D systems

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Tao, Hengcong, Yunnan Gao, Neetu Talreja, Fen Guo, John Texter, Chao Yan e Zhenyu Sun. "Two-dimensional nanosheets for electrocatalysis in energy generation and conversion". Journal of Materials Chemistry A 5, n. 16 (2017): 7257–84. http://dx.doi.org/10.1039/c7ta00075h.

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Souidi, Monia, Yvonne Sleiman, Ivana Acimovic, Jan Pribyl, Azzouz Charrabi, Volker Baecker, Valerie Scheuermann et al. "Oxygen Is an Ambivalent Factor for the Differentiation of Human Pluripotent Stem Cells in Cardiac 2D Monolayer and 3D Cardiac Spheroids". International Journal of Molecular Sciences 22, n. 2 (11 gennaio 2021): 662. http://dx.doi.org/10.3390/ijms22020662.

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Numerous protocols of cardiac differentiation have been established by essentially focusing on specific growth factors on human pluripotent stem cell (hPSC) differentiation efficiency. However, the optimal environmental factors to obtain cardiac myocytes in network are still unclear. The mesoderm germ layer differentiation is known to be enhanced by low oxygen exposure. Here, we hypothesized that low oxygen exposure enhances the molecular and functional maturity of the cardiomyocytes. We aimed at comparing the molecular and functional consequences of low (5% O2 or LOE) and high oxygen exposure (21% O2 or HOE) on cardiac differentiation of hPSCs in 2D- and 3D-based protocols. hPSC-CMs were differentiated through both the 2D (monolayer) and 3D (embryoid body) protocols using several lines. Cardiac marker expression and cell morphology were assessed. The mitochondrial localization and metabolic properties were evaluated. The intracellular Ca2+ handling and contractile properties were also monitored. The 2D cardiac monolayer can only be differentiated in HOE. The 3D cardiac spheroids containing hPSC-CMs in LOE further exhibited cardiac markers, hypertrophy, steadier SR Ca2+ release properties revealing a better SR Ca2+ handling, and enhanced contractile force. Preserved distribution of mitochondria and similar oxygen consumption by the mitochondrial respiratory chain complexes were also observed. Our results brought evidences that LOE is moderately beneficial for the 3D cardiac spheroids with hPSC-CMs exhibiting further maturity. In contrast, the 2D cardiac monolayers strictly require HOE.

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Souidi, Monia, Yvonne Sleiman, Ivana Acimovic, Jan Pribyl, Azzouz Charrabi, Volker Baecker, Valerie Scheuermann et al. "Oxygen Is an Ambivalent Factor for the Differentiation of Human Pluripotent Stem Cells in Cardiac 2D Monolayer and 3D Cardiac Spheroids". International Journal of Molecular Sciences 22, n. 2 (11 gennaio 2021): 662. http://dx.doi.org/10.3390/ijms22020662.

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Numerous protocols of cardiac differentiation have been established by essentially focusing on specific growth factors on human pluripotent stem cell (hPSC) differentiation efficiency. However, the optimal environmental factors to obtain cardiac myocytes in network are still unclear. The mesoderm germ layer differentiation is known to be enhanced by low oxygen exposure. Here, we hypothesized that low oxygen exposure enhances the molecular and functional maturity of the cardiomyocytes. We aimed at comparing the molecular and functional consequences of low (5% O2 or LOE) and high oxygen exposure (21% O2 or HOE) on cardiac differentiation of hPSCs in 2D- and 3D-based protocols. hPSC-CMs were differentiated through both the 2D (monolayer) and 3D (embryoid body) protocols using several lines. Cardiac marker expression and cell morphology were assessed. The mitochondrial localization and metabolic properties were evaluated. The intracellular Ca2+ handling and contractile properties were also monitored. The 2D cardiac monolayer can only be differentiated in HOE. The 3D cardiac spheroids containing hPSC-CMs in LOE further exhibited cardiac markers, hypertrophy, steadier SR Ca2+ release properties revealing a better SR Ca2+ handling, and enhanced contractile force. Preserved distribution of mitochondria and similar oxygen consumption by the mitochondrial respiratory chain complexes were also observed. Our results brought evidences that LOE is moderately beneficial for the 3D cardiac spheroids with hPSC-CMs exhibiting further maturity. In contrast, the 2D cardiac monolayers strictly require HOE.

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COLLINS, Richard F., Toby D. FLINT, Andreas HOLZENBURG e Robert C. FORD. "Structural changes in photosystem II after treatment with the zero-length bifunctional cross-linker 1-ethyl-3-(3-dimethylaminopropyl)carbodi-imide: an electron microscopic study". Biochemical Journal 319, n. 2 (15 ottobre 1996): 585–89. http://dx.doi.org/10.1042/bj3190585.

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Two-dimensional (2D) crystals of photosystem II (PS II) treated with various concentrations of the zero-length crosslinker 1-ethyl-3-(3-dimethylaminopropyl)carbodi-imide (EDC) were analysed by electron microscopy in conjunction with crystallographic image processing. The preparations were characterized by SDS/PAGE and oxygen-evolution measurements, and the effectiveness of cross-linking was monitored by measuring the level of protection afforded against high concentrations of NaCl and CaCl2, which normally remove extrinsic proteins from PS II. We found that low concentrations of EDC (0.25%) increase the order of 2D crystals of PS II. Treatments with EDC concentrations higher than 0.5% did not improve the order of 2D crystals but induced gross structural changes, which were correlated with a decrease in oxygen evolution activity. Structural changes due to cross-linking did not affect packing or symmetry of the 2D crystals, further supporting the conclusion that PS II has a monomeric nature in vivo.

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Khan, Aamar F., Edward P. Randviir, Dale A. C. Brownson, Xiaobo Ji, Graham C. Smith e Craig E. Banks. "2D Hexagonal Boron Nitride (2D-hBN) Explored as a Potential Electrocatalyst for the Oxygen Reduction Reaction". Electroanalysis 29, n. 2 (28 settembre 2016): 622–34. http://dx.doi.org/10.1002/elan.201600462.

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Luo, Hailan, Zhiyong Liu, Cuiyun Ma, An Zhang, Qunzhi Zhang e Fei Wang. "2D/2D KNbO3/MoS2 heterojunctions for piezocatalysis: Insights into interfacial electric-fields and reactive oxygen species". Journal of Environmental Chemical Engineering 11, n. 6 (dicembre 2023): 111521. http://dx.doi.org/10.1016/j.jece.2023.111521.

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Shim, JeonGhee, Young Chul Kang, Dong-Jin Kang e Myung Woo Han. "Fluxes and budgets of biogenic elements at the sediment-water interface of Marian Cove, King George Island". Antarctic Science 23, n. 4 (22 febbraio 2011): 358–68. http://dx.doi.org/10.1017/s0954102011000137.

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AbstractFluxes of dissolved oxygen and nutrients and vertical fluxes of particulate organic elements were investigated in the subtidal benthic environment of Marian Cove, King George Island, Antarctica, usingin situbenthic chambers and near-bottom sediment traps. Fluxes of dissolved oxygen, ammonium, phosphate, and silicate were comparable to those measured in temperate regions. Sediment oxygen consumption was a good indicator of organic respiration and elemental efflux at the benthic boundary layer of Marian Cove, with good positive correlations with ammonia (r2= 0.67), phosphate (r2= 0.57), and the C:N:P ratio (106:11.5:1.15) in the chamber water. A positive relationship (r2= 0.58) between settling particulate organic carbon flux and chlaconcentration suggests that water column biomass and production are direct sources of settling particles. According to element budgets in summer assessed using the fluxes, Jinand the sum of Joutand Jburialwere 15.9 ± 8.1 and 22.6 ± 8.2 mmol m-2d-1for carbon, 2.02 ± 0.54 and 2.46 ± 0.82 mmol m-2d-1for nitrogen, 0.07 ± 0.03 and 0.23 ± 0.08 mmol m-2d-1for phosphorus, and 12.4 ± 2.7 and 13.5 ± 5.0 mmol m-2d-1for silicon, respectively. There was a broad balance between sediment organic input and remineralized output for carbon and nitrogen at the benthic boundary layer of Marian Cove.

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Eiger, Sergio. "2D Advective-Diffusive Transport of Dissolved Oxygen in Channels". Journal of Environmental Engineering 121, n. 9 (settembre 1995): 668–70. http://dx.doi.org/10.1061/(asce)0733-9372(1995)121:9(668).

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Khan, Yasser, Donggeon Han, Adrien Pierre, Jonathan Ting, Xingchun Wang, Claire M. Lochner, Gianluca Bovo et al. "A flexible organic reflectance oximeter array". Proceedings of the National Academy of Sciences 115, n. 47 (7 novembre 2018): E11015—E11024. http://dx.doi.org/10.1073/pnas.1813053115.

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Transmission-mode pulse oximetry, the optical method for determining oxygen saturation in blood, is limited to only tissues that can be transilluminated, such as the earlobes and the fingers. The existing sensor configuration provides only single-point measurements, lacking 2D oxygenation mapping capability. Here, we demonstrate a flexible and printed sensor array composed of organic light-emitting diodes and organic photodiodes, which senses reflected light from tissue to determine the oxygen saturation. We use the reflectance oximeter array beyond the conventional sensing locations. The sensor is implemented to measure oxygen saturation on the forehead with 1.1% mean error and to create 2D oxygenation maps of adult forearms under pressure-cuff–induced ischemia. In addition, we present mathematical models to determine oxygenation in the presence and absence of a pulsatile arterial blood signal. The mechanical flexibility, 2D oxygenation mapping capability, and the ability to place the sensor in various locations make the reflectance oximeter array promising for medical sensing applications such as monitoring of real-time chronic medical conditions as well as postsurgery recovery management of tissues, organs, and wounds.

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Tedjo, William, Yusra Obeidat, Giovana Catandi, Elaine Carnevale e Thomas Chen. "Real-Time Analysis of Oxygen Gradient in Oocyte Respiration Using a High-Density Microelectrode Array". Biosensors 11, n. 8 (29 luglio 2021): 256. http://dx.doi.org/10.3390/bios11080256.

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Physiological events related to oxygen concentration gradients provide valuable information to determine the state of metabolizing biological cells. The existing oxygen sensing methods (i.e., optical photoluminescence, magnetic resonance, and scanning electrochemical) are well-established and optimized for existing in vitro analyses. However, such methods also present various limitations in resolution, real-time sensing performance, complexity, and costs. An electrochemical imaging system with an integrated microelectrode array (MEA) would offer attractive means of measuring oxygen consumption rate (OCR) based on the cell’s two-dimensional (2D) oxygen concentration gradient. This paper presents an application of an electrochemical sensor platform with a custom-designed complementary-metal-oxide-semiconductor (CMOS)-based microchip and its Pt-coated surface MEA. The high-density MEA provides 16,064 individual electrochemical pixels that cover a 3.6 mm × 3.6 mm area. Utilizing the three-electrode configuration, the system is capable of imaging low oxygen concentration (18.3 µM, 0.58 mg/L, or 13.8 mmHg) at 27.5 µm spatial resolution and up to 4 Hz temporal resolution. In vitro oxygen imaging experiments were performed to analyze bovine cumulus-oocytes-complexes cells OCR and oxygen flux density. The integration of a microfluidic system allows proper bio-sample handling and delivery to the MEA surface for imaging. Finally, the imaging results are processed and presented as 2D heatmaps, representing the dissolved oxygen concentration in the immediate proximity of the MEA. This paper provides the results of real-time 2D imaging of OCR of live cells/tissues to gain spatial and temporal dynamics of target cell metabolism.

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Inthanon, Janvikul, Ongchai e Chomdej. "Intrinsic Cellular Responses of Human Wharton’s Jelly Mesenchymal Stem Cells Influenced by O2-Plasma-Modified and Unmodified Surface of Alkaline-Hydrolyzed 2D and 3D PCL Scaffolds". Journal of Functional Biomaterials 10, n. 4 (18 novembre 2019): 52. http://dx.doi.org/10.3390/jfb10040052.

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Polycaprolactone (PCL), a hydrophobic-degradable polyester, has been widely investigated and extensively developed, to increase the biocompatibility for tissue engineering. This research was the first trial to evaluate the intrinsic biological responses of human Wharton’s Jelly Mesenchymal Stem Cells (hWJMSCs) cultured on alkaline hydrolysis and low-pressure oxygen plasma modified 2D and 3D PCL scaffolds, without adding any differentiation inducers; this has not been reported before. Four types of the substrate were newly established: 2D plasma-treated PCL (2D-TP), 2D non-plasma-treated PCL (2D-NP), 3D plasma-treated PCL (3D-TP), and 3D non-plasma-treated PCL (3D-NP). Physicochemical characterization revealed that only plasma-treated PCL scaffolds significantly increased the hydrophilicity and % oxygen/carbon ratio on the surfaces. The RMS roughness of 3D was higher than 2D conformation, whilst the plasma-treated surfaces were rougher than the non-plasma treated ones. The cytocompatibility test demonstrated that the 2D PCLs enhanced the initial cell attachment in comparison to the 3Ds, indicated by a higher expression of focal adhesion kinase. Meanwhile, the 3Ds promoted cell proliferation and migration as evidence of higher cyclin-A expression and filopodial protrusion, respectively. The 3Ds potentially protected the cell from apoptosis/necrosis but also altered the pluripotency/differentiation-related gene expression. In summary, the different configuration and surface properties of PCL scaffolds displayed the significant potential and effectiveness for facilitating stem cell growth and differentiation in vitro. The cell–substrate interactions on modified surface PCL may provide some information which could be further applied in substrate architecture for stem cell accommodation in cell delivery system for tissue repair.

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Li, Haobo, Jianping Xiao, Qiang Fu e Xinhe Bao. "Confined catalysis under two-dimensional materials". Proceedings of the National Academy of Sciences 114, n. 23 (22 maggio 2017): 5930–34. http://dx.doi.org/10.1073/pnas.1701280114.

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Confined microenvironments formed in heterogeneous catalysts have recently been recognized as equally important as catalytically active sites. Understanding the fundamentals of confined catalysis has become an important topic in heterogeneous catalysis. Well-defined 2D space between a catalyst surface and a 2D material overlayer provides an ideal microenvironment to explore the confined catalysis experimentally and theoretically. Using density functional theory calculations, we reveal that adsorption of atoms and molecules on a Pt(111) surface always has been weakened under monolayer graphene, which is attributed to the geometric constraint and confinement field in the 2D space between the graphene overlayer and the Pt(111) surface. A similar result has been found on Pt(110) and Pt(100) surfaces covered with graphene. The microenvironment created by coating a catalyst surface with 2D material overlayer can be used to modulate surface reactivity, which has been illustrated by optimizing oxygen reduction reaction activity on Pt(111) covered by various 2D materials. We demonstrate a concept of confined catalysis under 2D cover based on a weak van der Waals interaction between 2D material overlayers and underlying catalyst surfaces.

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Zhao, Yuxin, Siyuan Niu, Baichuan Xi, Zurong Du, Ting Yu, Tongtao Wan, Chaojun Lei e Siliu Lyu. "Recent Developments in Two-Dimensional Carbon-Based Nanomaterials for Electrochemical Water Oxidation: A Mini Review". Catalysts 14, n. 4 (25 marzo 2024): 221. http://dx.doi.org/10.3390/catal14040221.

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Water splitting is considered a renewable and eco−friendly technique for future clean energy requirements to realize green hydrogen production, which is, to a large extent, hindered by the oxygen evolution reaction (OER) process. In recent years, two−dimensional (2D) carbon−based electrocatalysts have drawn sustained attention owing to their good electrical conductivity, unique physicochemical properties, and excellent electrocatalytic performance. Particularly, it is easy for 2D carbon−based materials to form nanocomposites, which further provides an effective strategy for electrocatalytic applications. In this review, we discuss recent advances in synthetic methods, structure−property relationships, and a basic understanding of electrocatalytic mechanisms of 2D carbon−based electrocatalysts for water oxidation. In detail, precious, non−precious metal−doped, and non−metallic 2D carbon−based electrocatalysts, as well as 2D carbon−based confined electrocatalysts, are introduced to conduct OER. Finally, current challenges, opportunities, and perspectives for further research directions of 2D carbon−based nanomaterials are outlined. This review can provide significant comprehension of high−performance 2D carbon−based electrocatalysts for water-splitting applications.

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Huo, Jia-Min, Ying Wang, Jie Meng, Xin-Yi Zhao, Quan-Guo Zhai, Yu-Cheng Jiang, Man-Cheng Hu, Shu-Ni Li e Yu Chen. "π⋯π interaction directed 2D FeNi-LDH nanosheets from 2D Hofmann-MOFs for the oxygen evolution reaction". Journal of Materials Chemistry A 10, n. 4 (2022): 1815–20. http://dx.doi.org/10.1039/d1ta09921c.

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A two-dimensional (2D) MOFs transformation strategy was introduced to synthesize FeNi layered double hydroxides (FeNi LDHs) in NaBH4 solution, which show excellent OER catalytic activity in alkaline media.

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Schulman, Emily, Wei Wu e Dongxia Liu. "Two-Dimensional Zeolite Materials: Structural and Acidity Properties". Materials 13, n. 8 (12 aprile 2020): 1822. http://dx.doi.org/10.3390/ma13081822.

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Zeolites are generally defined as three-dimensional (3D) crystalline microporous aluminosilicates in which silicon (Si4+) and aluminum (Al3+) are coordinated tetrahedrally with oxygen to form large negative lattices and consequent Brønsted acidity. Two-dimensional (2D) zeolite nanosheets with single-unit-cell or near single-unit-cell thickness (~2–3 nm) represent an emerging type of zeolite material. The extremely thin slices of crystals in 2D zeolites produce high external surface areas (up to 50% of total surface area compared to ~2% in micron-sized 3D zeolite) and expose most of their active sites on external surfaces, enabling beneficial effects for the adsorption and reaction performance for processing bulky molecules. This review summarizes the structural properties of 2D layered precursors and 2D zeolite derivatives, as well as the acidity properties of 2D zeolite derivative structures, especially in connection to their 3D conventional zeolite analogues’ structural and compositional properties. The timeline of the synthesis and recognition of 2D zeolites, as well as the structure and composition properties of each 2D zeolite, are discussed initially. The qualitative and quantitative measurements on the acid site type, strength, and accessibility of 2D zeolites are then presented. Future research and development directions to advance understanding of 2D zeolite materials are also discussed.

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Liu, Junxian, Jack Jon Hinsch, Huajie Yin, Porun Liu, Huijun Zhao e Yun Wang. "β-Arsenene Monolayer: A Promising Electrocatalyst for Anodic Chlorine Evolution Reaction". Catalysts 12, n. 3 (5 marzo 2022): 296. http://dx.doi.org/10.3390/catal12030296.

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Materials innovation plays an essential role to address the increasing demands of gaseous chlorine from anodic chlorine evolution reaction (CER) in chlor-alkali electrolysis. In this study, two-dimensional (2D) semiconducting group-VA monolayers were theoretically screened for the electrochemical CER by means of the density functional theory (DFT) method. Our results reveal the monolayered β-arsenene has the ultralow thermodynamic overpotential of 0.068 V for CER, which is close to that of the commercial Ru/Ir-based dimensionally stable anode (DSA) of 0.08 V @ 10 mA cm−2 and 0.13 V from experiments and theory, respectively. The change of CER pathways via Cl* intermediate on 2D β-arsenene also efficiently suppresses the parasitical oxygen gas production because of a high theoretical oxygen evolution reaction (OER) overpotential of 1.95 V. Our findings may therefore expand the scope of the electrocatalysts design for CER by using emerging 2D materials.

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Huang, Bao-Bing, Zhi-Yong Luo, Jun-Jun Zhang e Zai-Lai Xie. "2D quasi-ordered nitrogen and sulfur co-doped carbon materials from ionic liquid as metal-free electrocatalysts for ORR". RSC Advances 7, n. 29 (2017): 17941–49. http://dx.doi.org/10.1039/c6ra28381k.

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Li, Qiaodan, Chaofan Yang, Lulu Wu, Hui Wang e Xiaoli Cui. "Converting benzene into γ-graphyne and its enhanced electrochemical oxygen evolution performance". Journal of Materials Chemistry A 7, n. 11 (2019): 5981–90. http://dx.doi.org/10.1039/c8ta10317h.

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Nivetha, Ravi, Sushant Sharma, Jayasmita Jana, Jin Suk Chung, Won Mook Choi e Seung Hyun Hur. "Recent Advances and New Challenges: Two-Dimensional Metal–Organic Framework and Their Composites/Derivatives for Electrochemical Energy Conversion and Storage". International Journal of Energy Research 2023 (13 febbraio 2023): 1–47. http://dx.doi.org/10.1155/2023/8711034.

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Metal–organic frameworks (MOFs), as a new generation of intrinsically porous extended crystalline materials formed by coordination bonding between the organic ligands and metal ions or clusters, have attracted considerable interest in many applications owing to their high porosity, diverse structures, and controllable chemical structure. Recently, 2D transition-metal- (TM-) based MOFs have become a hot topic in this field because of their high aspect ratio derived from their large lateral size and small thickness, as well as the advantages of MOFs. Moreover, 2D TM-based MOFs can act as good precursors to construct heterostructures with high electrical conductivity and abundant active sites for a range of applications. This review comprehensively introduces the widely adopted synthesis strategies of 2D TM-based MOFs and their composites/derivatives. In addition, this paper summarizes and highlights the recent advances in energy conversion and storage, including the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, CO2 reduction reaction, urea oxidation reaction, batteries, and supercapacitors. Finally, the challenges in developing these intriguing 2D layered materials and their composites/derivatives are examined, and the possible proposals for future directions to enhance the energy conversion and storage performance are reviewed.

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Yao, Bing, Rongsheng Li, Chenxi Zhang, Zhenjia Zhou, Zihao Fu, Xianlei Huang, Guowen Yuan, Jie Xu e Libo Gao. "Tuning the morphology of 2D transition metal chalcogenides via oxidizing conditions". Journal of Physics: Condensed Matter 34, n. 19 (3 marzo 2022): 195001. http://dx.doi.org/10.1088/1361-648x/ac54e5.

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Abstract Two-dimensional transition metal chalcogenides (TMCs) are emerging as an intriguing platform to realize nascent properties in condensed matter physics, materials science and device engineering. Controllable growing of TMCs becomes increasingly important, especially for the layer number, doping, and morphology. Here, we successfully tune the morphology of MoS2, MoSe2, WS2 and WSe2, from homogenous films to individual single crystalline grains only via changing the oxidizing growth conditions. The oxidization degrees are determined by the oxygen that adsorbed on substrates and the oxygen concentrations in reaction gas together. We find the homogenous films are easily formed under the reductive conditions, triangular grains prefer the weak oxidizing conditions, and medium oxidizing conditions bring in dendritic grains with higher oxygen doping and inhomogenous photoluminescence intensities from edge to interior regions shown in the dendritic grains. These growth rules under different oxidizing conditions are easily generalized to other TMCs, which also show potential for growing specific TMCs with designed oxygen doping levels.

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Zhou, Jie, Justinas Palisaitis, Joseph Halim, Martin Dahlqvist, Quanzheng Tao, Ingemar Persson, Lars Hultman, Per O. Å. Persson e Johanna Rosen. "Boridene: Two-dimensional Mo4/3B2-x with ordered metal vacancies obtained by chemical exfoliation". Science 373, n. 6556 (12 agosto 2021): 801–5. http://dx.doi.org/10.1126/science.abf6239.

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Extensive research has been invested in two-dimensional (2D) materials, typically synthesized by exfoliation of van der Waals solids. One exception is MXenes, derived from the etching of constituent layers in transition metal carbides and nitrides. We report the experimental realization of boridene in the form of single-layer 2D molybdenum boride sheets with ordered metal vacancies, Mo4/3B2-xTz (where Tz is fluorine, oxygen, or hydroxide surface terminations), produced by selective etching of aluminum and yttrium or scandium atoms from 3D in-plane chemically ordered (Mo2/3Y1/3)2AlB2 and (Mo2/3Sc1/3)2AlB2 in aqueous hydrofluoric acid. The discovery of a 2D transition metal boride suggests a wealth of future 2D materials that can be obtained through the chemical exfoliation of laminated compounds.

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Wang, Yuanzhe, Yanyan Zhou, Minze Han, Yaokai Xi, Huanhuan You, Xianfeng Hao, Zhiping Li et al. "Environmentally‐Friendly Exfoliate and Active Site Self‐Assembly: Thin 2D/2D Heterostructure Amorphous Nickel–Iron Alloy on 2D Materials for Efficient Oxygen Evolution Reaction". Small 15, n. 16 (aprile 2019): 1805435. http://dx.doi.org/10.1002/smll.201805435.

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Курбанова, Эльмира Джумшудовна, e Валерий Анатольевич Полухин. "STRENGTH AND FUNCTIONAL CHARACTERISTICS OF HEXA AND PENTAGONAL 2D MATERIALS. HYDROGEN". Physical and Chemical Aspects of the Study of Clusters, Nanostructures and Nanomaterials, n. 14 (15 dicembre 2022): 458–67. http://dx.doi.org/10.26456/pcascnn/2022.14.458.

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Проведен анализ синтезированных уникальных двумерных 2D-материалов с нанослойными гексагональными и пентагональными структурами (на основе углерода, кремния, олова, двойных соединений CN, BN, PdSe и тройных - BCN, CNP, PdSSe, ZnCP. Синтез этих материалов получен химическим паровым осаждением или эпитаксией металлов на заранее приготовленные подложки. Проведен также анализ прочностных и функциональных характеристик (электронных, оптических) созданных моделей с применением теории DFT в виде тройных монослоев с обоюдосторонним нанесением водорода на поверхности монослоя P-SiC: водород/p-SiC/водород. Выявлено, что наиболее динамически стабильным из них был слой p-SiC-4H с его двухсторонней водородной адсорбцией и хорошими свойствами. В этой статье также представлены сравнительно недавно полученные гекса- и пентагональные двумерные материалы не только элементов C, Si, Ge, B, но и сплавов CuNi, TiNi и соединений BiSb, CN, BN, PdSe и др. Так что с созданными новыми уникальными материалами - синтеза сверхпрочных, термостабильных нанокомпозитов, сверхпроводящих слоистых композитов (на основе Bi, Hg и Sb) открываются перспективы развития наноэлектроники, спинтроники, компьютерной техники, а также создания портабельных тензодатчиков, датчиков давления, газовых датчиков и катализаторов диализа воды с выделением водорода и кислорода. An analysis of synthesized unique two-dimensional 2D materials with nanolayer hexagonal and pentagonal structures (based on carbon, silicon, tin, binary compounds CN, BN, PdSe and ternary compounds - BCN, CNP, PdSSe, ZNCP) was carried out. The synthesis of these materials was performed by the chemical vapor deposition or metal epitaxy on pre-prepared substrates. The strength and functional characteristics (electronic, optical) of the created models were also analyzed using the DFT theory in the form of triple monolayers with double-sided deposition of hydrogen on the surface of the p-SiC monolayer: hydrogen/p-SiC/hydrogen. It was found that the p-SiC-4H layer with its two-sided hydrogen adsorption and good properties was the most dynamically stable. This article also presents relatively recently obtained hexa- and pentagonal two-dimensional materials not only for the elements C, Si, Ge, B, but also for CuNi, TiNi alloys and BiSb, CN, BN, PdSe, etc. compounds. So, with the new unique materials created - the synthesis of superstrong, thermostable nanocomposites, superconducting layered composites (based on Bi, Hg and Sb), prospects are opening up for the development of nanoelectronics, spintronics, computer technology, as well as the creation of portable strain gauges, pressure sensors, gas sensors and dialysis catalysts for water dialysis with the release of hydrogen and oxygen.

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Xu, Liang, Rashid Iqbal, Yijun Wang, Sana Taimoor, Leiduan Hao, Renhao Dong, Kaihui Liu, John Texter e Zhenyu Sun. "Emerging two-dimensional materials: Synthesis, physical properties, and application for catalysis in energy conversion and storage". Innovation Materials 2, n. 1 (2024): 100060. http://dx.doi.org/10.59717/j.xinn-mater.2024.100060.

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<p>Inorganic, organic, and hybrid two-dimensional (2D) materials are being developed for ever-expanding numbers of applications, though energy and catalysis remain the main drivers of their development. We present overviews of bottom-up and top-down synthetic strategies of such materials and examine manufacturing scalability issues. Mechanical, electrical, and thermal properties and their modulation are highlighted because they are fundamental to the above-mentioned drivers. The burgeoning importance of heterostructures in such materials, particularly for catalysis and electrode design and function is stressed. Detailed attention is given to applications of 2D materials to the electrocatalysis reactions: oxygen reduction, oxygen evolution, hydrogen evolution, carbon dioxide reduction, and nitrogen reduction. Water splitting, carbon dioxide reduction, and nitrogen reduction by photocatalysis are also examined. A perspective of expected advances in the expansion of applications and types of 2D materials, with a focus on heterostructure development, is presented in the conclusion.</p>

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