能源被認為是世界人口的重要需求,由于人口激增和工業(yè)革命,全世界對能源的需求大大增加。幾十年來,嚴峻的環(huán)境污染問題和化石燃料減少的趨勢不斷激勵著研究人員,科學(xué)家和政策制定者去探索替代能源以滿足世界人口對能源的需求。就可再生能源而言,氫(H2)燃料被視為清潔,可持續(xù)和環(huán)保的燃料。為了減少環(huán)境污染問題并增強可再生能源的能源供應(yīng)和儲存,通過電化學(xué)電解水分解制氫被認為是重要的可再生能源手段之一,其中借助聚合物質(zhì)子交換膜電解槽(PEMWE)技術(shù)產(chǎn)生清潔能源H2是目前主要手段。但是,由于在電解池的陽極室中發(fā)生的析氧反應(yīng)(OER)的緩慢動力學(xué),大大抑制了電解池產(chǎn)生的H2的速率。實際上,OER被認為是復(fù)雜且關(guān)鍵的半反應(yīng),該過程需要轉(zhuǎn)移四個電子來完成反應(yīng),與反應(yīng)標準熱力學(xué)數(shù)值1.23伏特相比,OER然后需要較大的過電勢來克服能量壁壘。目前,已證明貴金屬氧化物,尤其是二氧化銥(IrO2)和二氧化釕(RuO2)是有效生產(chǎn)氫氣的OER催化劑。但是,這些貴金屬非常昂貴,阻礙了該技術(shù)在工業(yè)規(guī)模上的商業(yè)化應(yīng)用。因此,如今最小化利用OER復(fù)合材料中貴重金屬并增強其活性和耐酸性被認為是一個巨大的挑戰(zhàn)。這也將會使可再生能源...

【文章頁數(shù)】：157 頁

【學(xué)位級別】：博士

【文章目錄】：
Abstract
摘要
Chapter Ⅰ Introduction
    1.1 Background
    1.2 Current environmental scenario
        1.2.1 Sources and occurrence of air pollution
        1.2.2 Sources and occurrence of water pollution
    1.3 Renewable energy sources
    1.4 Electrochemical approaches towards renewable energy
        1.4.1 Multifunctional electrochemical as-synthesized composites
            1.4.1.1 Trifunctionality electrocatalytic materials
            1.4.1.2 Bifunctional electrocatalytic materials
    1.5 Oxygen evolution reaction (OER) electrocatalysts
        1.5.1 Doping of transition metals into noble metal oxides
        1.5.2 Doping of noble metals into transition metal oxides
        1.5.3 Perovskites based OER materials
        1.5.4 Mixed oxides based OER materials
    1.6 Current Status of the OER catalysts
    1.7 Aim of the research study
        1.7.1 Materials, experimental methods, and characterization techniques
        1.7.2 Mixed oxide composite of IrO₂ and MoO3

        1.7.3 Mixed oxide composite of RuO₂ and MoO₃

        1.7.4 Mixed oxide composite of IrO₂ and WO₃

        1.7.5 Conclusions and future recommendations
    1.8 Innovations in current research study
Chapter Ⅱ Materials, experimental methods, and characterization techniques
    2.1 Experimental materials, chemical reagents, and instruments
        2.1.1 List of instruments
        2.1.2 List of chemical reagents, and materials
    2.2 Experimental methods
        2.2.1 Hydrothermal method
        2.2.2 Two step chemical method
    2.3 Physical characterization techniques
        2.3.1 Energy-dispersive X- ray spectroscopy (EDS)
        2.3.2 Brauner-Emmett-Teller (BET) surface areas
        2.3.3 X-Ray powder diffraction (XRD) analysis
        2.3.4 Scanning, field emission and transmission electron microscopic images(SEM,FE-SEM, TEM)
        2.3.5 X-Ray photoelectron spectroscopy (XPS) analysis
    2.4 Electrochemical performance analysis
        2.4.1 Electrodes preparations
        2.4.2 Reference electrode calibration
        2.4.3 Solution resistance measurements
        2.4.4 Voltammetry measurements
        2.4.5 Electrochemical properties calculations
            2.4.5.1 Tafel slope calculations
            2.4.5.2 Bulk mass activity calculations
            2.4.5.3 Turn over frequency (TOF) calculations
Chapter Ⅲ Unraveling the beneficial electrochemistry of IrO₂/MoO₃ hybrid as a highly stable and efficient OER catalyst
    3.1 Introduction
    3.2 Synthesis of IrO₂-MoO₃ Composites
    3.3 Results and discussion
        3.3.1 Structural morphologies of as-synthesized composites
        3.3.2 XRD,EDS,and HAADF-STEM analysis
        3.3.3 XPS study
        3.3.4 Electrochemical performance of composites
    3.4 Summary
Chapter Ⅳ Boosted up stability and activity of oxygen vacancy enriched RuO₂/MoO₃ mixed oxide
    4.1 Introduction
    4.2 Synthesis of Ru_xMo_1-xO_δcomposites
    4.3 Results and discussion
        4.3.1 Morphological analysis of various composites
        4.3.2 XRD and EDS analysis
        4.3.3 Electrochemical characterization of composites
        4.3.4 XPS study
    4.4 Summary
Chapter V Facile synthesis of IrO₂ nanoparticles decorated＠WO₃ as mixed oxide composite for outperformed oxygen evolution reaction
    5.1 Introduction
    5.2 Fabrication of different composites
        5.2.1 Synthesis of WO₃ composite
        5.2.2 Synthesis of IrO₂/WO₃ composites
        5.2.3 Synthesis of pure IrO₂ composite
    5.3 Results and discussion
        5.3.1 Structures of as-synthesized composites
        5.3.2 XRD characterization and compositional analysis
        5.3.3 Electrochemical characterizations of mixed oxide composites
        5.3.4 Reaction mechanism of oxygen evolution reaction (OER) in acidic media
        5.3.5 XPS study of mixed oxide composites
    5.4 Summary
Chapter Ⅵ Conclusions and future recommendations
    6.1 Schematic conclusions
    6.2 Future recommendations
References
Published work during PhD
Acknowledgement



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