【作者】 杨广武；

【导师】 力虎林；

【作者基本信息】 兰州大学 ， 分析化学， 2009， 博士

【摘要】 燃料电池（FC）和电化学电容器（EC）是目前电化学能量存储/转化领域研究开发的重点和热点。燃料电池由于具有能量转换效率高、对环境友好、容量可调等优点而受到世界各国的极大关注。电化学电容器结合了物理电容器高功率及传统电池高能量密度的优点,其应用领域广泛,已成为新型化学电源研究中的热点之一,但是无论是燃料电池还是电化学电容器,其性能表现、制造成本以及使用寿命都在很大程度上的依赖于器件的电极材料和结构。本论文综述了当前该两类器件电极材料的最新研究进展,并就相关电极材料制备,改性以及在这两类能量存储/转化装置中的应用进行了深入的研究,主要内容如下:1.采用的π-π吸附技术和热处理的方法在多壁碳纳米管上沉积Pt纳米粒子（Pt/MWCNTs）。通过透射电子显微镜（TEM）和X-射线衍射仪（XRD）等手段对Pt/MWCNTs进行了表征。电化学实验结果表明,Pt/MWCNTs对甲醇具有很好电催化氧化作用和电化学稳定性。2.在乙醇溶液中,将卞硫醇保护的银纳米粒子通过π-π相互作用沉积在多壁碳纳米管表面上（Ag/MWCNTs）。通过TEM和XRD等手段对Ag/MWCNTs进行了表征。电化学实验结果表明,Ag/MWCNTs对肼具有很好电催化氧化作用。3.以Brij 56/MnAc₂/KAc水溶液体系的六角相溶致液晶为模板,利用恒电位电沉积技术在AAO/Ti/Si模板的Ti基底上成功制备出了介孔MnO₂纳米线阵列电极。小角XRD,场发射扫描电子显微镜（FESEM）、TEM等测试证明该介孔纳米线材料具有多孔的三维结构。电化学测试表明,MnO₂纳米线阵列电极的比容量达到了496Fg^-1。证明这种电极在电化学电容器方面具有潜在的应用价值。4.在Ni（NO）₂水溶液中,通过直流电化学沉积的方法在镍网上沉积了一层Ni（OH）₂,制备出了Ni（OH）₂-Ni foam电化学电容器电极材料。通过FESEM和XRD等手段对Ni（OH）₂-Ni foam进行了表征。电化学测试表明表明,Ni（OH）₂-Ni foam的单电极比电容达到了3152 Fg^-1,是已报道的最大的单电极比电容。进一步的研究表明,沉积温度和退火温度对Ni（OH）₂-Ni foam电极电化学性能具有明显的影响。更多还原

【Abstract】 Fuel cell （FC） and electrochemical capacitor （EC） are two kinds of important energy storage/conversion devices that are being studied widely at present. On account of large energy conversion efficiency and green environmental conservation, PEMFC has attracted much attention all over the world. EC has already become one of the research interests related to new chemical energy sources studies because of its higher power density and longer cycle life than secondary batteries and its higher energy density compared to conventional electrical double-layer capacitors. Generally, the cost and the life of FC and EC are restricted by the material and the structure of the electrode.In this thesis, we have reviewed the newest development in the research of electrode materials of both FC and EC devices, prepared relevant electrode materials and explored their applications in these two kinds of devices in detail. The main content is as follows:1. Multi-walled carbon nanotubes （MWCNTs） were functionalized viaπ-πinteraction with benzyl mercaptan. The subsequent bonding of thiol groups with Pt offered strong adhesion of Pt nanoparticles on MWCNT surface. Thermal treatment was introduced as the essential step of catalyst preparation. The structure and morphology of the resulting Pt/MWCNT composite were characterized by transmission electron microscopy （TEM） and X-ray diffraction （XRD）, the results show that Pt nanoparticles were highly dispersed and effectively adhered on MWCNTs. The excellent electrocatalytic activity of the Pt/MWCNT composite for the oxidation of methanol was demonstrated by cyclic voltammetry.2. A simple method is devised to deposit highly monodispersed Ag nanoparticles （about 5 nm） on MWCNTs, which started from an initial modification of Ag nanoparticles with benzyl mercaptan molecules. By simply tuning the relative ratio of Ag catalyst to MWCNTs in solution, Ag/MWCNT composite with different Ag content can be achieved. The as-prepared Ag/MWCNT composite materials showed high electrocatalytic activity towards hydrazine oxidation, which was ascribed to the high dispersion of Ag nanoparticles on MWCNT surface. 3. We report here for the first time on the synthesis of mesoporous MnO₂ nanowire array on conductive Ti/Si substrate The morphology of the material is significantly controlled by the conjunct template of anodic aluminum oxide （AAO） and the hexagonal phase of a lyotropic liquid crystalline Low-angle XRD, field emission scanning electron microscope （FESEM） and TEM studies show that the nanowire has a coarse structure, which provides a high specific surface area. Galvanostatic charge/discharge measurements reveal that this porous, three-dimensional electrode material has excellent electrochemical capacitance between potential range of -0.1-0.9 V, and a maximum specific capacitance as high as 493 F g^-1 could be achieved in Na₂SO₄ (0.5 mol L^-1) solution at a charge/discharge current density of 4 A g^-1.4.Ni（OH）₂ thin film with porous and three-dimensional （3D） nanostructures was simply fabricated on nickel foam substrate by direct current electrodeposition from aqueous solution of Ni（NO₃）₂. The morphology and composition of the electrodeposited layer coated on nickle network were characterized by FESEM and XRD Cyclic voltammetric, galvanostatic charge/discharge and electrochemical impedance spectroscopic measurements reveal that the as-prepared electrode material has ultrahigh capacitance between potential range of -0.05-0.45 V, and a maximum specific capacitance as high as 3152 F g^-1 could be achieved in 3% KOH solution at a charge/discharge current density of 4 A g^-1. The capacitive performances of Ni（OH）₂-Ni electrode are approximately dependent on the deposition temperature and the anneal temperature.更多还原