【作者】 刘健；

【导师】 高岩；

【作者基本信息】 大连理工大学 ， 化学工程（专业学位）， 2020， 硕士

【摘要】 作为传统能源,化石能源是有限的,同时化石燃料的燃烧会产生大量的温室气体和一些有毒的污染物,产生很严重的环境污染问题。因此,开发一些可持续的清洁能源来取代传统的化石能源成为解决上述问题最为可行的方法。氢气作为一种清洁并且来源丰富的能源载体受到了研究者们的广泛关注。获得氢气的途径有很多,水分解反应就是一条非常重要的途径,其中的水氧化反应（OER）包含四个质子和电子的转移以及O-O键的形成,是水分解反应的关键步骤,因此开发高效的催化剂来提高反应的动力学并降低其过电位是十分重要的。早期研究者们主要研究的是单金属水氧化催化剂,后来大量的研究表明,基于单金属的水氧化催化剂的催化能力是有限的,而通过向单金属催化剂中掺杂一些其他金属后,可以调整催化剂材料的电子结构并降低OER中间体的吸附能,同时在催化过程中不同金属之间具有一定的协同作用,这能够大幅提升催化剂的催化能力。基于以上这些背景,本文采用水热和电化学沉积的方法在泡沫镍基底上原位生长出碱式碳酸钴纳米线后,再将Fe负载在纳米线的表面,最终制得Fe-CCH/NF水氧化电极。在1 M KOH电解液中,当电流密度达到100 mA/cm²时,过电位仅有255 mV,塔菲尔曲线的斜率为32.1 mV/dec,并且在10 mA/cm²的电流密度下长时间电解50 h仍能稳定存在。此外,还通过简单的电化学沉积的方法依次在三维导电基底泡沫镍上沉积CeO₂和FeOOH水氧化催化剂,然后采用高温磷化的方法在管式炉中煅烧后制备出所需的FeP-CeO₂/NF电极。该电极在1 M KOH溶液中,达到100 mA/cm²的电流密度仅需要245 mV的过电位,塔菲尔曲线的斜率只有39.1 mV/dec,并且可以稳定工作50 h以上。更多还原

【Abstract】 Fossil energy is limited and non-renewable as a traditional energy source on the earth.Meanwhile,the burning of fossil fuels will generate a large number of greenhouse gases and some toxic pollutants,which will cause serious environmental pollution problems.Therefore,developing some sustainable and clean energy to replace traditional energy is the most feasible way to solve this problem.Hydrogen as a clean and abundant energy carrier has attracted widespread attention from researchers around the world.Water decomposition reaction is a very important way to produce hydrogen gas.The oxygen evolution reaction（OER）,which includes four proton and four electron transformations together with O-O bond formation,is the basis of water splitting process.Therefore,it is important to develop efficient catalysts to accelerate the OER kinetics and reduce the overpotential associated with this reaction.Early researchers mainly studied single-metal water oxidation catalysts,and a large number of later studies showed that the catalytic ability of single-metal-based water oxidation catalysts was limited.By doping a single metal catalyst with some other metal,the electronic structure of the catalyst can be adjusted and the adsorption energy of the OER intermediate can be reduced.At the same time,there is a certain synergy between different metals in the catalytic process,which can greatly improve the catalytic effect.Based on these backgrounds,in this paper,hydrothermal and electrochemical deposition methods were sequentially used to grow alkaline cobalt carbonate nanowires in situ on a nickel foam substrate and support Fe on the surface of the nanowires to finally obtain Fe-CCH/NF water oxidation electrode.In the electrolyte of 1 M KOH,the electrode exhibits outstanding performance for OER with an overpotential of only 255 mV at a current density of 100 mA/cm²,the slope of tafel curve is 32.1 mV/dec,and it can work steadily for more than 50 h under the current density of 10 mA/cm2.In addition,a simple electrochemical deposition method was used to load CeO₂ and FeOOH water oxidation catalyst on the three-dimensional conductive base nickel foam,and then the required FeP-CeO₂/NF electrode was prepared by calcination in a tube furnace using a high-temperature phosphating method.The electrode exhibits outstanding performance for OER with an overpotential of only 245 mV at a current density of 100 mA/cm²,a Tafel slope as low as 39.1 mV/dec and excellent durability for 50 h at a current density of 10mA/cm² in an alkaline solution.更多还原