Дисертації з теми "Graphene Oxide Thin Film"
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Tekenya, Ronald. "Graphene-modified pencil graphite mercury-film electrodes for the determination of trace metals by cathodic adsorptive stripping voltammetry." University of the Western Cape, 2018. http://hdl.handle.net/11394/6552.
Повний текст джерелаThis project focuses on the simple, fast and highly sensitive adsorptive stripping voltammetry detection of Nickel and Cobalt complexed with DMG and Nioxime respectively at a Reduced Graphene Oxide modified pencil graphite electrode in water samples. This research as well demonstrates a novel electrochemically reduced graphene oxide (ERGO)/mercury film (MF) nanocomposite modified PGE, prepared through successive electrochemical reduction of graphene oxide (GO) sheets and in-situ plated mercury film. The GO and graphene were characterized using FT-IR, HR-SEM, HR-TEM, XRD and Raman spectroscopy. The FT-IR results supported by Xray diffraction analysis confirmed the inclusion of oxygen moieties within the graphitic structure during the chemical oxidation step. Microscopic and spectroscopic analysis was used to confirm the stackings of graphene on the pencil electrode. The ERGO-PG-MFE, in combination with a complexing agents of [dimethylglyoxime (DMG) and Nioxime] and square-wave cathodic stripping voltammetry (SW-CSV), was evaluated towards the individual determination of Ni2+ and Co2+ respectively and simultaneous determination of both metals from the combination of DMG and Nioxime mixture. A single-step electrode pre-concentration approach was employed for the in-situ Hg-film electroplating, metal-chelate complex formation and its non-electrolytic adsorption at – 0.7 V for the individual analysis of Ni2+ and Co2+. The current response due to metal-ligand(s) complex reduction were studied as a function of experimental variables; deposition/accumulation potential, deposition/accumulation time, rotation speed, frequency and amplitude and carefully optimized for the individual determination of Ni2+and Co2+ and simultaneous determination of Ni2+ and Co2+ at low concentration levels (μg L-1) in 0.1 M NH3- NH4Cl buffer solution (pH 9.4) solution. The recorded limit of detection for the individual analysis of Ni2+and Co2+ was found to be 0.120 μg L-1 and 0.220 μg L-1 respectively, at an accumulation time of 120 s for both metals. The recorded limit of detection of the simultaneous analysis of Ni2+ and Co2+ was found to be 6.1 μg L-1 and 1.8 μg L-1 respectively. The ERGO-PG-MFE further demonstrated a highly selective stripping response toward all trace metal analysis. The testing of the applicability of graphene-based sensor and method in laboratory tap water samples was evaluated. This electrode was found to be sensitive enough to detect metal ions in the tap water samples at the 0.2 μg L-1 level for individual analysis and 0.001 μg L-1 for simultaneous, well below WHO standards.
Sanga, Nelia Abraham. "Determination of heavy metals at the electrochemically reduced graphene oxide mercury film electrode (ERGO-HgF-PGE) using adsorptive stripping voltammetry." University of Western Cape, 2020. http://hdl.handle.net/11394/7718.
Повний текст джерелаThis work reports the use of a pencil graphite electrode (PGE) as inexpensive and sensitive electrochemical sensing platform fabricated by using electrochemically reduced graphene oxide (ERGO) in conjunction with an in-situ plated thin mercury film. For the first time the ERGOHgF-PGE sensor is proposed for simultaneous detection of cadmium (Cd2+), copper (Cu2+), lead (Pb2+) and zinc (Zn2+) using N-Nitroso-N-phenylhydroxylamine (cupferron) as complexing agent by square-wave adsorptive cathodic stripping voltammetry (SW-AdCSV). The technique is based on the adsorption of cupferron- metal ion complexes onto the surface of the ERGO-HgFPGE at 0.1 V for 60 s carried out in 0.1 M acetate buffer solution (pH 4.6). The synthesized graphene oxide (GO) and graphene nanosheets (GNs) were characterized using different analytical techniques such as FT-IR which confirms the presence of oxygen moieties embedded in the graphitic structure and further demonstrated by UV-Vis, validating the synthesis of GO
2023
Le, Louie. "Nanocomposites and graphene oxide thin film coatings on the surface of fiber reinforced composites for enhanced flame retardancy." Thesis, Wichita State University, 2013. http://hdl.handle.net/10057/6425.
Повний текст джерелаPant, Bharat Raj. "A Comparative Study on P-type Nickel Oxide and N-type Zinc Oxide for Gas Sensor Applications." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1525473245395728.
Повний текст джерелаDorenkamp, Yvonne Jeannette. "Inelastic H-Atom scattering from ultra-thin films." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E49B-7.
Повний текст джерелаFerrah, Djawhar. "Etude des propriétés physico-chimiques d'interfaces par photoémission." Thesis, Ecully, Ecole centrale de Lyon, 2013. http://www.theses.fr/2013ECDL0048/document.
Повний текст джерелаThe main objective of this thesis is to study the chemical and physical properties at the surface or at the interface between thin layers by photoemission spectroscopy (XPS), photoelectron diffraction (XPD), and time resolved photoemission (PTR) . The experiments were conducted using an Alka source at INL or soft -X ray synchrotron radiation at Soleil, the French national Synchrotron facility. The first photoemission study has been performed on platinum deposited on thin Gd2(h layers grown by Molecular Bearn Epitaxy (MBE) on Si (111) substrate. The charge transfer between Pt and 0 at the interface causes a chemical shift to higher binding energies without changing the characteristic shape of the metal XPS peak. The XPD study shows that Pt is partially crystallized into two (111)-oriented do mains on Gd20 3 (111) with the in-plane epitaxial relationships [11 0] Pt (111) / / [11 0] Gd203 (111) and [101] Pt(111)/ / [11 0] Gd20 3 (111). In addition to bi-domains formation of platinum Pt (111) on Gd20 3 (111), a new ordered phase of platinum oxide Pt02 at the Pt/ Gd203 interface have been observed. The study of the background of the polar curves depending of the morphology has shown, that the film of Pt does not wet on the oxide, due to the low energy of interaction at the interface compared to the Pt thin layer. The second study has been interested to the photoemission time-resolved study of non-reactive metal / semiconductor model system. We have studied the thin layer gold (Au) growth on silicon (Si) substrate before and during annealing in TEMPO beam line (synchrotron Soleil).The XPS study, shows before annealing the formation of silicon native oxide on heterostructure at ambient temperature. The desorption of silicon oxide during annealing at low temperature induce photoemission intensity decreases with time. The desorption of oxide and alloy formation (AuSi) induce distribution of pits with cubic form at silicon surface due to gold etching activity. The third photoemission study has concerned thin films of a few layers of graphene obtained by solid-state graphitization from 6H-SiC (0001) substrates have been studied by X-ray photoelectron spectroscopy (XPS) and X-ray photoelectron diffraction (XPD). The Cls core-level has been resolved into components, which have been associated with carbon from bulk SiC, carbon from graphene and carbon at the interface graphene/ 6H-SiC (0001). Then, the intensity of each of these components has been recorded as a function of polar (azimuth) angle for several azimuth (polar) angles. These XPD measurements provide crystallographic information which clearly indicates that the graphene sheets are organized in graphite-like structure on 6H-SiC(0001), an organization that results of the shrinking of the 6H-SiC (0001) lattice after Si depletion. Finally the decoupling of graphene from 6H-SiC (0001) substrate by oxygen intercalation has been studied from the XPS point of view. Finally, photoemission study has concerned thin film of InP (phosphor indium ) islands grown by Molecular Bearn Epitaxy (MBE) on SrTi03 (001) bulk substrate have been investigated by X-ray photoelectron spectroscopy and diffraction (XPS/ XPD).Integration of III-V semi-conductor on silicon wafer, via SrTi03 buffer is currently the subject of intense research because of its potentially interesting applications in future nano-optoelectronics. The Ols, Sr3d, Ti2p, In3d, and P 2p core level area have been studied as function of azimuth angle for different polar angles. Comparison of the XPD azimuth curves of Sr3d and In3d shows that islands InP are oriented (001) with an in-plane epitaxial relationship [110] InP(001 ) // [100] SrTi03 (001). AFM images shows that InP islands are regularly dispersed on the surface. Their shape is a regularly facetted half-sphere
Ly, Kally Chein Sheng 1992. "Fabricação e caracterização de filme fino regenerável hidrofóbico." [s.n.], 2017. http://repositorio.unicamp.br/jspui/handle/REPOSIP/330349.
Повний текст джерелаDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin
Made available in DSpace on 2018-09-02T14:50:41Z (GMT). No. of bitstreams: 1 Ly_KallyCheinSheng_M.pdf: 2442128 bytes, checksum: 86716c6c19fa3a9db425b32c36463141 (MD5) Previous issue date: 2017
Resumo: Materiais biomiméticos são inspirados em estruturas biológicas para a obtenção de propriedades e funcionalidades específicas. Dentre os materiais biomiméticos, os que são capazes de se regenerar (self-healing) despertaram grande interesse pelo potencial de aplicação em diversas áreas. Para ilustrar, alguns materiais autorregeneráveis poliméricos apresentam regeneração múltipla, necessitando apenas de água para que a regeneração ocorra em alguns minutos, aumentando consideravelmente a proteção mecânica da superfície contra desgastes, danos mecânicos entre outros. Entretanto, múltiplas imersões em água ou em meios aquosos pode degradar o material e neste contexto este projeto visa incorporar a hidrofobicidade a um sistema regenerável. Desta forma, o material regenerável hidrofóbico, durante sua regeneração imersa em água, poderá diminuir a interação da superfície não danificada com a água, reduzindo corrosões e degradações devido a meios aquosos. Estudamos a nanoestruturação de materiais através da técnica de automontagem por adsorção física (LbL, do inglês Layer-by-Layer) utilizando os polieletrólitos poli(etileno imina) (PEI) e poli(ácido acrílico) (PAA), a fim de produzir revestimentos capazes de se regenerar a danos mecânicos micrométricos. Adicionalmente, foram incorporados a estes dois materiais nanofolhas de óxido de grafeno reduzido (rGO) funcionalizados com poli(cloridrato de alilamina) (GPAH) e poli(estireno-sulfonato de sódio) (GPSS), com o intuito de verificarmos um aumento de resistência a abrasão do material e alterações nas propriedades elétricas na nanoestrutura formada para aumentar o potencial de aplicação em eletrônica flexível. A arquitetura molecular (GPAH-PEI/GPSS-PAA)60 foi caracterizada com espectroscopia Raman, medidas de ângulo de contato, microscopia de força atômica, medidas elétricas e nanoindentação. Foi observada boa regeneração do material após 15 minutos de imersão em água a temperatura ambiente em um dano mecânico da ordem de 10 micrômetros. Também observamos boa hidrofobicidade do filme LbL (GPAH-PEI/GPSS-PAA)60 ( teta = 136º), e medidas de microscopia de força atômica e perfilometria indicaram, respectivamente, rugosidade superficial de 55 nm em uma área de (2 ?m x 2 ?m) e espessura de filme de 30 ?m. A análise Raman apontou para uma forte interação das nanofolhas de rGO com os polímeros, corroborando o tem caráter elétrico isolante do filme (GPAH-PEI/GPSS-PAA)60, que apresentou função trabalho ~ 5,2 eV e condutividade elétrica da ordem de 10-7 S/cm, que acreditamos resultar das fortes interações das nanofolhas com os polímeros. Por fim, medidas de nanoindentação indicaram que a incorporação de nanofolhas de GPSS e GPAH aumentou em 10 vezes a dureza do nanocompósito formado, sem comprometer a regeneração
Abstract: Biomimetic materials are inspired in biological structures to obtain specific properties and functionalities and among them, those capable of self-healing brought great interest due to high potential of application in different areas. To illustrate, some polymeric self-healing materials present multiple regeneration in the presence of water, with the regeneration occurring within a few minutes, increasing considerably the mechanical protection of a surface against wear and mechanical damage among others. Nevertheless, multiple immersions in water or in aqueous media can degrade the material and in this context this project aims the incorporation of hydrophobicity to a self-healing system. In this way, the self-healing, hydrophobic material during its immersion in water may decrease the interaction of the damaged surface with water, reducing corrosion and degradation due to aqueous media. We study the nanostructuration f materials through the layer-by-layer (LbL) technique using poly(ethylene imine) (PEI) and poly(acrylic acid) (PAA) in order to produce self-healing coatings from micrometric mechanical damages. In addition, we also incorporate to these materials reduced graphene oxide (rGO) functionalized with poly(allylamine hydrochloride) (GPAH) and poly(styrene-sodium sulfonate) (GPSS), with the purpose of verifying an increase in the mechanical abrasion resistance of the material and changes in the electrical properties of the nanostructures formed to increase the potential application in flexible electronics. The molecular architecture (GPAH-PEI/GPSS-PAA)60 was characterized by Raman spectroscopy, contact angle measurements, atomic force microscopy, electrical measurements and nanoindentation. It was observed good self-healing capacity after 15 min f immersion in water at room temperature in a mechanical scratch of the order of 10 micrometers. It was also observed good hydrophobicity in the (GPAH-PEI/GPSS-PAA)60 LbL film ( teta = 136º) and atomic force microscopy and perfilometer indicate, respectively, surface roughness of 55 nm in a (2 ?m x 2 ?m) area and film thickness of 30 ?m. Raman analysis pointed out to a strong physical interaction between the rGO nanoplatelets with the polymeric materials, corroborating the strong insulating nature of (GPAH-PEI/GPSS-PAA)60 film that displayed a work function of 5.2 eV and electrical conductivity of 10-7 S/cm, which we believe results from the strong interactions of the nanosheets with the polymers. Finally, nanoindentation measurements indicated that the incorporation of GPAH and GPSS nanoplatelets increased hardness by 10 times, without compromising the regeneration
Mestrado
Física
Mestra em Física
1543078/2015
CAPES
Lacovig, Paolo. "Electronic structure, morphology and chemical reactivity of nanoclusters and low-dimensional systems: fast photoemission spectroscopy studies." Doctoral thesis, Università degli studi di Trieste, 2010. http://hdl.handle.net/10077/3685.
Повний текст джерелаL'obiettivo di questa tesi è l'applicazione della spettroscopia di fotoemissione allo studio di nanoparticelle supportate e di sistemi a bassa dimensionalità. Ad una primo periodo dedicato allo sviluppo del rivelatore e del software per un nuovo analizzatore d'energia per elettroni installato presso la linea di luce SuperESCA ad Elettra, è seguita una fase durante la quale ho eseguito una serie di esperimenti mirati ad esplorare le potenzialità del nuovo apparato sperimentale. Il primo risultato ottenuto riguarda la comprensione della relazione che intercorre tra le variazioni della reattività chimica del sistema Pd/Ru(0001) e il numero degli strati di Pd cresciuti in modo pseudomorfico sul substrato di rutenio. La risoluzione temporale raggiunta con la nuova strumentazione ci ha permesso di studiare processi dinamici su una scala temporale fino ad ora inaccessibile per la spettroscopia di fotoemissione dai livelli di core: in particolare abbiamo studiato la crescita del grafene ad alta temperatura sulla superficie (111) dell'iridio e la reattività chimica di nanocluster di Pt supportati su MgO. Nel primo caso abbiamo messo in evidenza come la formazione del grafene proceda attraverso la nucleazione di nano-isole di carbonio che assumono una peculiare forma di cupola. Nel secondo caso siamo riusciti a seguire sia la dinamica del processo di adsorbimento di CO, sia la reazione CO + 1/2 O2 -> CO2 sulle nanoparticelle di Pt depositate su un film ultra-sottile di ossido di magnesio. Infine, abbiamo caratterizzato la morfologia di nanoparticelle di Pd, Pt, Rh e Au cresciute su diversi substrati a base di carbonio, in particolare grafite, nanotubi a parete singola e grafene. Tra i vari risultati abbiamo compreso come l'interazione metallo-substrato dipenda dalla dimensione delle nano-particelle e abbiamo evidenziato il ruolo centrale dei difetti del substrato nei processi di nucleazione e intercalazione.
The objective of this thesis is the application of photoelectron spectroscopy for the investigation of supported nanoclusters and low-dimensional systems. After a first stage devoted to the development of the detector and the software for the electron energy analyser installed on the SuperESCA beamline at Elettra, during the PhD project I've performed a series of experiments aimed to explore the capabilities of the new experimental apparatus. One of the first results concerns the understanding of the relation between the modifications in the chemical reactivity of the Pd/Ru(0001) system and the thickness of the pseudomorphically grown Pd overlayer. The temporal resolution achieved with the new experimental set-up allowed us to study dynamical processes on a new time scale, in particular the graphene growth process at high temperature on the Ir(111) surface and the chemical reactivity of Pt nanoclusters supported on MgO. In the former case, we discovered that graphene formation proceeds via preliminary nucleation of dome-shaped C nano-islands. In the second case, we succeded in following both the dynamics of CO adsorption process and the CO + 1/2 O2 -> CO2 reaction on Pt nanoclusters grown on a ultra-thin film of magnesium oxide. Finally, the morphology of Pd, Pt, Rh and Au nanoclusers grown on different carbon-based substrates (namely graphite, single-walled carbon nanotubes and graphene) has been characterized. Among the results we report the understanding of the dependence of the metal-substrate interaction on the cluster size and the role of defects in the nucleation and intercalation processes.
XXII Ciclo
1972
Guan, Jingcheng. "Modelling zinc oxide thin-film growth." Thesis, Loughborough University, 2018. https://dspace.lboro.ac.uk/2134/36311.
Повний текст джерелаLi, Sonny X. "Nitrogen doped zinc oxide thin film." Berkeley, Calif. : Oak Ridge, Tenn. : Lawrence Berkeley National Laboratory ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy, 2003. http://www.osti.gov/servlets/purl/821916-VLVAK9/native/.
Повний текст джерелаPublished through the Information Bridge: DOE Scientific and Technical Information. "LBNL--54116" Li, Sonny X. USDOE Director. Office of Science. Basic Energy Sciences (US) 12/15/2003. Report is also available in paper and microfiche from NTIS.
Özkan, Zayim E., and N. Karamahmutoglu. "Carbon Nanotubes Doped Vanadium Oxide Thin Film." Thesis, Sumy State University, 2012. http://essuir.sumdu.edu.ua/handle/123456789/35004.
Повний текст джерелаMeng, Keng-Yuan. "Magnetic Skyrmions in Oxide Thin Film Heterostructures." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1562856036665345.
Повний текст джерелаZhang, Jiawei. "Oxide-semiconductor-based thin-film electronic devices." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/oxidesemiconductorbased-thinfilm-electronic-devices(c8cde776-b68b-47b5-ab63-382a86dbb94b).html.
Повний текст джерелаČuboň, Tomáš. "Studium optických vlastností tenkých vrstev organických fotovoltaických článků." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2017. http://www.nusl.cz/ntk/nusl-316198.
Повний текст джерелаHan, Sanggil. "Cu2O thin films for p-type metal oxide thin film transistors." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/285099.
Повний текст джерелаRossi, Leonardo. "Flexible oxide thin film transistors: fabrication and photoresponse." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14542/.
Повний текст джерелаBarnes, Jean-Paul L. P. Barnes. "TEM studies of thin film oxide/metal nanocomposites." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398136.
Повний текст джерелаLloyd, Adam L. "Modelling silver thin film growth on zinc oxide." Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/24860.
Повний текст джерелаYoung, Sheng-Yu. "DLC thin film assisted zinc oxide nanowires growth." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8613.
Повний текст джерелаThesis research directed by: Dept. of Materials Science and Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
Gavanier, Beatrice. "Stability of thin film insertion electrodes." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324003.
Повний текст джерелаBeckel, Daniel. "Thin film cathodes for micro solid oxide fuel cells." kostenfrei, 2007. http://e-collection.ethbib.ethz.ch/view/eth:29741.
Повний текст джерелаWang, Chao-Hsiung. "The growth of thin film epitaxial oxide-metal heterostructures." Thesis, University of Cambridge, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368667.
Повний текст джерелаBrown, J. R. "Tin oxide thin film gas sensors deposited by MOCVD." Thesis, Keele University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.434038.
Повний текст джерелаLee, S. "Physics and modeling of oxide semiconductor thin film transistors." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1400467/.
Повний текст джерелаBarquinha, Pedro. "Transparent oxide thin-film transistors: production, characterization and integration." Doctoral thesis, Faculdade de Ciências e Tecnologia, 2010. http://hdl.handle.net/10362/5380.
Повний текст джерелаFlack, Natasha. "Thin film components for solid oxide fuel Cells (SOFCs)." Thesis, University of Liverpool, 2014. http://livrepository.liverpool.ac.uk/2007271/.
Повний текст джерелаAdam, Suhare A. "Thin Film Complex Oxide Proton Conductors: Synthesis and Applications." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:33493335.
Повний текст джерелаEngineering and Applied Sciences - Applied Physics
Pecunia, Vincenzo. "Solution-based polymeric/metal-oxide thin-film transistors and complementary circuits." Thesis, University of Cambridge, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708401.
Повний текст джерелаREMONDINA, JACOPO. "Ga-rich oxide-in-oxide glass ceramics: from bulk to thin film devices." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2020. http://hdl.handle.net/10281/263429.
Повний текст джерелаIn this thesis I present the work I have carried out during my PhD on Ga-oxide containing nanostructured glass-ceramic films as a potential breakthrough for the implementation of this class of material in planar geometry for applications in the field of optoelectronics. In the last three years, my investigations have been aimed at understanding the relationship between the occurrence of nanostructuring – analysed through a detailed structural studies by means of different microscopy and diffractometric techniques as a function of deposition conditions and post-deposition treatments – and the physical mechanisms of charge transport and polarization taking place in oxide-in-oxide films. The studied material was produced by RF sputtering deposition starting from a glass target of Li, Na, Si, Ga and Ge mixed oxide. As a consequence of the deposition process we have obtained partially crystallized material with Ga-rich nanocrystals incorporated in the remaining amorphous matrix. Through atomic force microscopy, x-ray reflectivity, 2D-x-ray diffraction, 2D-small angle x-ray scattering - also employing synchrotron radiation facilities - we have fully characterized the nanostructured films at different length scales, from few nm to few microns. The detailed analysis of the results shows the formation of multiple anisotropic spinel Ga-oxide nanocrystals with size of about 3 nm, forming larger lenticular aggregates with significant differences between the in-plane and the out-of-plane dimensions. As a result of the investigation of differently treated samples, the study also shows that size distribution and morphology of the nanostructures can be controlled by deposition conditions, duration and temperature of post-deposition thermal treatments. Starting from the knowledge of the structural features, the research activity has been directed to the deep understanding of the charge transport properties resulting from the nanostructured nature of the material, including the Ga2O3 semiconductor nanophase and the dielectric host matrix. The electrical response – analysed with the aid of complex impedance spectroscopy – turns out to be the results of multiple contributions to transport and charging mechanisms by the matrix and the nanophase, including the effects of the internal interfaces. The data suggest that the charge transport is sustained by a combination of thermally activated hopping and tunnelling mechanisms mediated by the percolation path built up by the nanostructured features of the material. Interestingly, the overall response gives preliminary evidences of electrical plasticity, making nano-glassceramic thin films potential candidates as key systems in advanced devices for brain-inspired oxide-in-oxide fully inorganic memories.
Huang, Yi-Wen, and 黃怡雯. "Low-Temperature Reduction of Thin Graphene Oxide Film." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/35869832541255533902.
Повний текст джерела國立中央大學
化學工程與材料工程學系
103
The graphene oxide nanoparticles obtained from anodic graphite by electrochemical exfoliation, followed by electrophoretic deposition onto stainless steel or nickel substract. Another way to deposit graphene particles on non-conductive substract is used to produce graphene film, which named Evaporative Deposition(ED). By ED, graphene films can be deposit on polymer substracts like PEN and formed a flexible graphene film. The graphite film formed was reduced in two ways, vacuum treatment with heating up to 100℃ and ethanol treatment with heating up to 220℃. The wetting properties are determined by contact angle measurement. The advancing and receding contact angles of graphene oxide film are 38.4° and 15.5o, respectively. This result reveals the thin film is rather hydrophilic. After the reduction treatment, the advancing and receding contact angle increased to 83.1° and 50.5°, respectively, indicating that the surface of graphene oxide film becomes more hydrophobic. By the analysis of TGA, Raman, XRD and XPS, the results proved that both of the reduction treatment had attained a reduction effect. After the reduction, a graphene film was obtained and the resistivity of the film is 9×10^(-4) Ω∙cm.
Wang, Guan-Ying, and 王冠穎. "Preparation of Thin Film with Reduced Graphene Oxide." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/f6fc74.
Повний текст джерела逢甲大學
化學工程學系
107
In order to improve the interface situation that might be encountered in producing multi-layer structured device, a method using graphene oxide (GO) undergoes modification, adsorption and chemical reduction of was proposed in this study to prepare electrically conducting graphene thin films. Modified GO is able to enhance the adhesion between adjacent two layers of different materials when it is deposited as an interfacial layer. First we used a large amount of oil-water interface to graft long-chain alkyl groups to one side of GO by amidaion reaction of the -COOH groups (carboxyl group) on GO and the -NH2 groups (amine group) of dodecylamine, resulting in planar GO surfactant (GO-SFT). Second, the -OH groups (hydroxyl groups) out of hydrolysis of the silane coupling agent condensed with other wardly, -OH groups of its kind and with those on the ITO glass. The long-chain alkyl groups of silane making the face out making the surface hydrophobic. Third, the GO-SFT is dissolved in water with the hydrophobic substrate immersed. The hydrophobic ends of the GO-SFT were fused with those on the surface so that the hydrophilic ends of GO-SFT face outwardly. Finally, using aqueous hydrazine solution, the hydrophilic functional groups of GO-SFT were removed, rendering reduced GO (RGO), which enhanced the electrical conductance of the adsorbed layer of graphene conductivity is increased. It was found in previous study that GO-SFT possesses a critical micelle concentration (CMC) in aqueous solution, indicating that it can form micelles in water and change the surface tension. In this study, we successfully adsorbed GO-SFT onto a hydrophobic surface, reduced to RGO, and created a large-area conductive thin film of graphene.
Yang, Chang-Ying, and 楊長穎. "Large area graphene – cobalt manganese oxide thin film for oxygen evolution reaction." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/14084524668459287138.
Повний текст джерела國立中山大學
化學系研究所
104
It is necessary to develop clean and green energy because of the shortage of non-renewable energy. The hydrogen and oxygen generated by water splitting is one of the solution for clean energy. However, energy required for water splitting is usually greater than energy generated by water splitting. Oxygen evolution reaction (OER) is the main reason of excessive energy consumption in the splitting process, thus it is necessary to prepare a catalyst to promote the OER. In this research, by a simple redox method with heating, we successfully synthesized cobalt manganese oxide hydroxide (CMOH) catalyst. This method is fast and simple; efficiently deposit catalytic thin film on large area substrate even on complex surfaces. At first, we used cobalt sulfate as precursor to prepare catalytic films (CMOH-sulfate, CMOH-S) for electrochemical measurement. However, the films (CMOH-acetate, CMOH-A) prepared by cobalt acetate have superior optical properties to CMOH-S, so we chose cobalt acetate for subsequent experiments. To further understand the difference between CMOH-S and CMOH-A, We characterized these two thin film by a series of characterization. The results of UV-visible and AFM show that the thickness of CMOH-A is smaller than CMOH-S thus has higher transmittance. CMOH-A have transmittance of 87.15% with thickness of 60 nm versus CMOH-S having 60.39% transmittance and 120 nm thickness. We further confirmed the thickness of CMOH-A to be 5 to 10 nm by TEM (rather than 60 nm by AFM), and the composition is amorphous. Despite the difference on optical property, CMOH-S and CMOH-A exhibit almost the same on OER activity. To study the reason, we altered the length of CMOH-A films, knowing that the active sites actually lie at the interface of catalyst and FTO glass. Finally, after covering a layer of graphene on the catalytic thin films and go through 500ºC calcination under Ar, we tremendously raise the stability of OER catalyzing process, with only 7.6% decay of current after 3000 circles scanning and still remain at same over potential (0.47 V at 10 mA cm-2).
Liu, Ding-Kun, and 劉定坤. "Preparation of silk nanofibril/graphene oxide thin film nanocomposite membrane for nanofiltration." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/scxae2.
Повний текст джерела中原大學
化學工程研究所
106
In this study, silk nanofibril(SNF) is used as main material of nanofiltration membrane. After fibrilling and crystallizing, silk fibroin(SF) transfer itself to SNF. SNF is pressure-filtrated on HPAN substrate to form composite membrane. FT-IR, TGA and DSC were chosen to characterize the fine structure and obtain the most cocoon-like fine structure which make it have the best performance compared to the rest SF membrane. UV-vis was used for solubility test of SFs and SNF. Surface properties and NF tests of SNF composite membrane and SNF/GO nanocomposite membrane were obtained by SEM, XPS, W.C.A and filtration set-up respectively. Among all of the SFs and SNF membranes, SNF have 18.55LMH of the flux and 86.15% of the rejection for Na2SO4 due to its hydrophilic crystal structure. The flux gets twice and the rejection is fixed after 5% GO addition. Furthermore, SNF/GO nanocomposite membrane have at least 94% of rejection for negatively charged organic dyes.
Khan, Mustaque Ali. "Efficient Photodetectors Based on Reduced Graphene Oxide." Thesis, 2016. https://etd.iisc.ac.in/handle/2005/4379.
Повний текст джерелаZhan, Hao-Zhong, and 詹皓仲. "The Affect of Different Reducing Conditions on Graphene Oxide Thin Film Semiconductor Characteristics." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/61507988147736173449.
Повний текст джерела國立中正大學
機械工程學系暨研究所
101
This thesis aims to analyze the structural characteristics of the graphene oxide (GO) with different degree of reduction by heating with various temperatures (from27℃ to 500℃) in a high vacuum (3 ~ 5 x10-6 torr) and different thickness are investigated.First, the use of graphene oxide aqueous of solution process is formed in two different film thickness by two ways: (1) Dip-coating, about 20 nm and (2) Spin-coating, about 1 ~ 5 nm. The reduced GO thin films were characterized by X-ray photoelectron spectroscopy, Raman spectroscopy and electrical transport measurements, respectively. The electrical measurements indicated that the mobility of thick film can improve about 2~4 order after thermal reduction. Moreover, it is observed that GO FET devices show p-type semiconducting behavior before reduction but when the same device is tested after the thermal reduction at 300℃, it shows n-type semiconducting behavior. However, it just only observed at thick films, the thinner films always shows p-type semiconducting even when the reducing temperature rise to 500℃. The effect of high-temperature on the functional groups of GO film is evidently examined using X-ray photoelectron spectroscopy and Raman spectroscopy. The results indicated that the thick film can effectively remove the oxygen-containing functional groups by observed the atomic oxygen-to-carbon (O/C) ratio from 2.78 decrease to 0.88 and restore its graphic structure compared to the thinner film from 3.01 decrease to 1.86. The Raman measurements show that the G and 2D peaks have different doping dependence to check the behavior of GO.
Chiang, Ju-Yun, and 姜如芸. "Feasibility of Polydopamine/Graphene Oxide Thin-Film Composite Membrane for Forward Osmosis Application." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/33tsea.
Повний текст джерела國立清華大學
材料科學工程學系
105
In pursuance of addressing the global water shortage problem, this work was designed to fabricate carbon materials-based forward osmosis thin-film composite (FO-TFC) membranes with high flux and high salt rejection properties. In this study, a novel method has been developed which was conducted by coating the surface of a reduced graphene oxide (rGO) modified poly(ethylene terephthalate) (PET) nonwoven fabric with polydopamine/graphene oxide (PDA/GO) prior to the interfacial polymerization of trimesoyl chloride (TMC) and m-phenylenediamine (MPD). Results showed that coating of the PDA/GO layer on the front-side of PET nonwoven substrate facilitated the formation of a denser selective polyamide(PA)layer during interfacial polymerization process to reduce reverse salt flux; the PDA/GO layer on the back-side of PET nonwoven endowed the substrate with catechol and ethylamino groups to enhance the hydrophilicity, which result in an increase in water flux. The TFC membranes fabricated by coating rGO on Ahlstrom 3324 PET nonwoven surfaces followed by coating of PDA/GO (with 80 μg/ml GO) and interfacial polymerization of PA showed a highest water flux of 3.64 LMH and the Ahlstrom 3254 PET nonwoven with same procedure demonstrated a lowest reverse salt flux 0.77 gMH in static FO test using deionized water as the feed along with 1 M NaCl draw solution in the FO mode. It showed that the feasibility of this novel method to fabricate FO-TFC membrane with good properties.
"Synthesis and Characterization of Thionated Reduced Graphene Oxides and Their Thin Films." Doctoral diss., 2013. http://hdl.handle.net/2286/R.I.21014.
Повний текст джерелаDissertation/Thesis
Ph.D. Chemistry 2013
Chen, Yi-Shiang, and 陳奕翔. "Preparation and characterization of MnOx/graphene oxide nanocomposite thin films." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/38751880443947495543.
Повний текст джерела大同大學
材料工程學系(所)
101
This research mainly manganese oxide / graphene oxide as a composite material, the use of graphene oxide with high specific surface area in order to enhance the reaction of manganese oxide. Scan using SEM EDS mapping graphene oxide of manganese in the distribution of the surface, namely that the addition of potassium permanganate different weight ratio will be 125% coverage is wide. The XRD and EPR, respectively, adding that the high proportion of potassium permanganate is obtained when a larger proportion of manganese (IV) and capacitance value is higher. Add different weight ratios of carbon black with different weight ratios of potassium permanganate prepared electrode potentiostat (Jiehan 500 electrochemical workstation) for cyclic voltammetry tests find its capacitance value. The results showed that the addition of different weight ratio of 40% to 100% of carbon black and potassium permanganate test strip has a higher capacitance value 58.809 F / G.
Lee, Chun-Yuan, and 李浚源. "Properties of graphene thin films derived from high temperature reduced graphene oxide/polyethylene glycol." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/39346699920515877541.
Повний текст джерела中原大學
化學研究所
100
Graphene with fast electron mobility, high mechanical strength, high conductivity and transparent characteristics, therefore, becomes very wide applications in electronic components. In this study, graphene was reduced from graphene oxide (GO) by using Hummer’s methods. By adding commercially available polyethylene glycol (PEG) with molecular weight 600, 6000, 20000, and 35000 for slurry formation, we developed the graphene films on glass substrate with good conductivity for electrode applications. The characteristics of graphene/PEG films were studied by using SEM, UV-vis, four proble point conductivity measurement, Raman spectroscopy, and AFM. It was found that PEG with molecular weight around 600~6000 is a better choice for the formation of graphene film on glass substrate in term of conductivity and their trasparancy.
Akther, Nawshad. "Development of Thin-Film Composite Membranes Incorporated With Graphene Oxide and Derivatives for Forward Osmosis Processes." Thesis, 2020. http://hdl.handle.net/10453/149327.
Повний текст джерелаGraphene oxide (GO) has been used to improve the anti-fouling and separation performance of the thin-film composite (TFC) membranes. Nonetheless, very few studies provided an in-depth explanation of the possible interaction between GO and polymer matrix that alter the membrane properties and performance. Thus, the overall aim of this study was to develop high-performance GO-based polyamide (PA) TFC forward osmosis (FO) membranes by systematically investigating the effect of GO and its derivatives on the modified membranes. First, polyvinyl alcohol (PVA)/GO hydrogel was coated on the PA surface to improve the membrane anti-fouling property. Second, the GO flake’s lateral size was reduced to decrease PA defects and improve membrane performance. Next, Aquaporin was added with GO in the PA layer to improve the membrane selectivity as Aquaporin healed the non-selective PA defects created by the GO flakes. Finally, the effect of GO quantum dots (GQDs) on the interfacial polymerization (IP) reaction and membrane performance at both macroscopic and microscopic levels was investigated both experimentally and using molecular dynamics (MD) simulation. GQDs decreased the IP reaction rate by reducing the diffusivities of PA monomers, reduced water permeability by acting as barriers to water molecules when present at a high concentration near the PA surface, and formed non-selective voids at the PA layer when present at very high loading.
YANG, CHIH-PENG, and 楊志鵬. "Characteristics of Graphene-oxide Thin Film and its Bi-layer Structure for Resistance Random Access Memory Applications." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/n7d569.
Повний текст джерела國立高雄應用科技大學
電子工程系碩士班
104
Graphene has many advantageous properties and it has been studied for many applications. Because of process integration and various promising properties, graphene oxide (GO) also attracts much interest. This thesis investigated graphene oxide for applications of resistive random access memory (RRAM). The GO film also stacked on a SiO2 layer to be a bi-layer structure for RRAM applications. The GO RRAM device can be inversely switched by dc voltages and the related characteristics were also investigated. In addition, the influence of water vapor on the GO RRAM devices were also investigated. The first part, Al/GO/Al structure was investigated. This structure shows non-polar resistive switching behavior. However, there is some difference between the resistive switching behaviors in different polarities. Due to the process procedures, interface layer is thicker in the bottom electrode than in the top electrode. Therefore, the interface layer in the bottom electrode can store less oxygen ions than the interface layer in the top electrode; thus, the resistive switching in the negative polarity is poorer than in the positive polarity. The resistive switching in the positive polarity shows smaller switching variation, and better switching reliabilities such as long retention (>10^4 s) and good endurance (>10^3 cycles). The second part investigated the resistive switching properties of Cu/GO/SiO2/Pt structure in air. The GO film with layer structure and defects can limit Cu diffusion and thus improved the switching stability. The Cu/GO/SiO2/Pt structure has more stable resistive switching behavior than the Cu/SiO2/Pt structure. The Cu/GO/SiO2/Pt structure has long retention (>10^4 s) and good endurance (>3x10^3 cycles). The third part investigated the resistive switching properties of Cu/GO/SiO2/Pt structure in N2. Water vapor assists Cu ionization procedure from the Cu electrode into SiO2 layer. Therefore, the Cu/SiO2/Pt structure can resistively switch in air, but can not switch in N2. The GO film has lots of oxygen-related groups and thus it can help the Cu ionization in N2. Thus, the Cu/GO/SiO2/Pt structure can stably switch in N2 and also has good memory reliability.
Thomas, Rajesh. "Investigations on Graphene/Sn/SnO2 Based Nanostructures as Anode for Li-ion Batteries." Thesis, 2013. http://etd.iisc.ac.in/handle/2005/3460.
Повний текст джерелаThomas, Rajesh. "Investigations on Graphene/Sn/SnO2 Based Nanostructures as Anode for Li-ion Batteries." Thesis, 2013. http://etd.iisc.ernet.in/2005/3460.
Повний текст джерелаKun-ChinHsieh and 謝坤晉. "Effect of Annealing Treatment on Thin Film Microstructure, Electrical and Optical Properties in the Indium Gallium Zinc Oxide/Titanium/Graphene/Polyimide Composite Films." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/u7x3pe.
Повний текст джерела國立成功大學
機械工程學系
105
This thesis use CVD method to create high quality graphene. First, we investigate graphene quality by Raman Analysis, Four-Point Probe and microstructure analyses. After a long test, we have made a high quality single-layer graphene successfully, and use the wetting transfer method to transfer this graphene to polyimide substrate. At last, depositing Ti and IGZO on graphene/polyimide to prepare a composite film by Magnetron Sputter. The results show that the sheet resistance of the samples with the graphene film is 10 times lower than that the samples without graphene. In addition, the carrier mobility also increased significantly, the results show that the use of graphene will elevate the carrier mobility by 30 to 60%. The application of nano-indentation system was found that the deposition of graphene can make a substantial rise in overall hardness about 60%. In this experiment, the oxygen content of samples was measured at room temperature and 100 ℃, 200 ℃ and 300 ℃ for 1 hour. It was found the IRO2 increased and internal residual stress was lower by increasing the annealing temperature. The increase of oxygen vacancies and the decrease of residual stress can improve the electrical properties of the film greatly. The carrier mobility of the film increases and the resistivity of the film decreases significantly. The results show that the addition of a layer of titanium increases the electrical properties of the thin film and the adhesion between the IGZO layer and the PI substrate and improve the electrical properties of IGZO. Besides, Annealing treatment affects the transmittance of the film. When the annealing temperature increases, the crystallinity of the film becomes stronger and the lattice arrangement is neater.
Chen, Wei-Chun, and 陳崴群. "Influence of concentration of reduced graphene oxide on properties of sol-gel prepared Al-doped Zinc oxide thin films." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/3upq2s.
Повний текст джерела國立中興大學
光電工程研究所
101
The addition of reduced graphene oxide (RGO) to aluminum doped zinc oxide was studied and analysis conducted on film for its electrical and optical characteristics. Sol-gel was applied in a circular pattern on glass substrate with the weight concentration of 0.0 wt%, 1.0 wt%, 1.5 wt% and 3.0 wt% as the proportion of mixing. A gaseous mixture of Ar:H2=9:1 was passed through furnace pipe and the substrate was annealed in 500℃ for an hour. In electric measurement, the resistivity was 1.11ⅹ10-1 Ω-cm for RGO-free AZO film, and the lowest resistivity was 8.11ⅹ10-3 Ω-cm with RGO at 1.0 wt%. For optical analysis, when 1.0 wt% of RGO is added, the transmittance of AZO film dropped from 92% without addition to 81% with addition.The experiment showed that RGO absorbed part of visible light and thus reduced the transmittance of AZO film. When analyzing surface measurement using a scanning electron microscope(SEM), it clearly showed that the RGO particles were distributed evenly across the surface of AZO film. The composition analysis using energy dispersive spectrometer (EDS) revealed carbon content in the AZO film, demonstrating that RGO was mixed effectively in the sol-gel. In the X-ray diffraction (XRD) analysis, the increase of RGO mixing concentration contributed to the increasing grain size of crystals on the surface. When mixing to 3.0 wt%, the 2θ angle of refraction peak shifted to the right from 34.42° with no mixing to 34.4°. It showed that the different mixing proportions of RGO at various concentrations had influence on the distribution of crystalline structure of the film.
Zbeda, Salma Gumaa Amar. "Multilayer graphene modified metal film electrodes for the determination of trace metals by anodic stripping voltammetry." 2013. http://hdl.handle.net/11394/3802.
Повний текст джерелаIn this study multilayer graphene nanosheets was synthesize by oxidizing graphite to graphene oxide using H2SO4 and KMnO4 followed by reduction of graphene oxide to graphene using NaBH4. The graphene nanosheets were characterized by Fourier Transform Infrared (FTIR) and Raman spectroscopy, high resolution transmission electron microscopy (HRTEM), Scanning electron microscopy (SEM) and X-ray diffraction (XRD). HRTEM images showed that the multilayer graphene were obtained. The graphene was immobilized directly onto a glassy carbon electrode using the drop coating technique followed by the in situ deposition of mercury, bismuth or antimony thin films to afford graphene modified glassy carbon metal film electrodes (Gr-GC-MEs). The experimental parameters (deposition potential, deposition time, rotation speed, frequency and amplitude) were optimized, and the applicability of the modified electrode was investigated towards the individual and simultaneous determination of Zn2+, Cd2+ and Pb2+ at the low concentration levels (μg L-1) in 0.1 M acetate buffer (pH 4.6) using square wave anodic stripping voltammetry (SWASV). The detection limits values for the Gr-GC-HgE was 0.08, 0.05 and 0.14 μg L-1 for Zn2+, Cd2+ and Pb2+, respectively. The Gr-GC-BiE the detection limits for was 0.12, 0.22 and 0.28 μg L-1 for Zn2+, Cd2+ and Pb2+ while the detection limits for the Gr-GC-SbE was 0.1, 0.3 and 0.3 μg L-1 for Zn2+, Cd2+ and Pb2+, respectively. A Gr-GCE prepared without any binding agents or metal film had detection limits for Zn2+, Cd2+ and Pb2+ of 3.9, 0.8 and 0.2 μg L-1 for Zn2+, Cd2+ and Pb2+. Real sample analysis of which was laboratory tap water was performed using the Gr-GCMEs. Only Gr-GC-HgE was sensitive enough to detect metal ions in the tap water samples at the 3ppb level whereas, the GC-BiE and GC-SbE detected the metal ions at the 10 μg L-1 to 30 μg L-1 level.
Chiou, Chuang-Fu, and 邱創富. "Electrical and humidity sensing properties of reduced graphene oxide thin film fabricated by layer-by-layer covalently anchoring on flexible substrate." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/06803273987508265099.
Повний текст джерела中國文化大學
化學系應用化學碩士班
102
Novel flexible humidity sensors were fabricated by layer-by-layer (LBL) covalently bonding graphene oxide (GO) to a gold electrode on a plastic substrate using a peptide chemical protocol and then reducing in-situGO film to a partially reduced GO film. The effect of the duration of reduction of GO film on the electrical and humidity propertiesof the reduced GO film was investigated. This flexible impedance-type humidity sensor exhibited a strong water resistance, a wide working range of humidities, a short response/recovery time, a weak dependence on temperature and good long-term stability. The different complex impedance plots obtained at low and high relative humidity indicated that the ions dominate the conductance of the anchored partially reduced GO film.
Yang, You-Hao. "Processing and Gas Barrier Behavior of Multilayer Thin Nanocomposite Films." Thesis, 2012. http://hdl.handle.net/1969.1/ETD-TAMU-2012-08-11685.
Повний текст джерелаCHEN, CHIAO-YI, and 陳喬毅. "A Study of the Electrophoretic Deposition of Graphene Oxide Thin Films in Asymmetrical AC Electric Fields." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/63tay6.
Повний текст джерела大葉大學
醫療器材設計與材料碩士學位學程
106
In the present study, graphene oxides (GrO) were synthesized by the Modified Hummer method with natural graphite powder as the raw material. The chemical structures and the surface morphology of the as-synthesized GrO were characterized by Raman and FE-SEM, respectively where aqueous GrO dispersions were prepared by adding aliquots of alcohol as solvent. The GrO thin films were prepared by electrophoretic deposition (EPD) over Indium Tin Oxide (ITO) glass substrates in asymmetric alternating current (AAC) and direct current (DC) electric fields, respectively. A preliminary study was conduct to find the appropriate EPD operation window after which the as-deposited GrO films by different deposition duration (5, 10, 20, 30 s), at identical operation voltage and frequency were compared comprehensively to investigate the effects of various modes of electric fields on the properties of the deposited GrO films. For AAC-EPD mode, all the three common waveforms has been choose, including square wave, square wave and sine wave, respectively. The former (square wave) could be named as the unbalanced electric field whose waveform was asymmetric in which the positive and negative area of the same size. In contrast, the remaining two waveforms could not meet the requirement of unbalanced electric field, i.e., a net DC current flows toward a given electrode leading to a DC and/or pulse-DC mode-like electric field. It shows that, compared to those deposited by DC-EPD, the deposition rate for those deposited by AAC modes were apparently much slower whereas different kind of waveform has made little difference in the rate of GrO film deposition. For those deposited by AAC-EPD with waveform of both square and sine wave, the behaver of rate increment about deposition time did follow the relationship of Hamker equation whereas the triangular wave did not show similar linear relationship. The complexity of the deposition behavior under the AAC electric fields could be attributed to the Stotz-Wien effect where the variation of electric filed strength with applied voltage were nonlinear, leading to different films structure and properties. It is noteworthy that for AAC-EPD films with square waveform, there is no hydrogen evolving on the cathode surface owing that all charges were flowed within the double layers in the vicinity of electrodes. In summary, the best result was obtained by AAC-EPD with square waveform at 40V, 50Hz, 25% duty cycle with deposition duration of 30s under which the as-deposited GrO films has compact surface morphology with RMS surface roughness of 4.40 nm, lowest sheet resistance of 25.93 0.85(/), and optical transmittance of 84.591%. By applying AAC-EPD with waveform of sine and triangular wave, the wrinkle on film surface becomes prominent, whereas both the optical transparency and electric conductivity for the as-deposited GrO films were deteriorated accordingly which might be ascribed to the hydrogen evolution at cathode surface during the prolonging deposition process.
WANG, YIN-YIN, and 王尹吟. "A Study on Hybrid Thin Film of Ag Nanowire and Reduced Graphene Oxide Prepared by H2-Low Damage Plasma as Flexible Transparent Electrode." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/13806060659432834588.
Повний текст джерела