Novel Interface And Study On CO₂ Electrolysis Of Nano Metal/conducitive Ceramics

With the development of modern civilization and industry,global warming has become one of the most concerned environmental problems duing to the "greenhouse effect".Excessive burning of coal,oil and natural gas has emitted a lot of greenhouse gases,and carbon dioxide is currently the highest greenhouse gas in the atmosphere.How to utilize and reduce the content of CO2 in the atmosphere is a very challenging and meaningful work.Electrochemical reduction of carbon dioxide(CO2)using renewable electricity can continue to achieve this goal.Solid oxide electrolyzer(SOE)is a device operated at high temperature,which can reduce polarization loss and use process heat to the maximum.The technology is mainly derived from solid oxide fuel cell(SOFC),and it is not perfect.Many efforts are needed in the design and optimization of new materials to meet the requirements of the application of solid oxide electrolysis cell(SOE)In many electrochemical systems,active interface plays an important role in determining the performance and life of energy materials.The nanoscale active interface is obtained by the method of in-situ growth of nanoparticles from the substrate.With the help of XRD,XPS,TG,SEM and TEM techniques,the phase,valence state,oxygen vacancy concentration,nanoscale morphology and electrochemical properties of cathode materials of different substrates(metal based electrode,metal ceramic based electrode and fluorite based electrode)were studied.By controlling the content of in situ growth MnOx on metal substrate(Ni),Ni/11%MnOx cathode exhibited the highest electrochemical performance.Ni/11%MnO,cathode shows excellent long-term performance without CO safe gas at 800 ? and 1.4 V.By controlling the content of in situ growth MnOx on the metal-ceramic substrate(Ni-YSZ),the Ni-YSZ/3%MnOx cathode exhibited the highest electrochemical performance.By regulating the proportion of in situ growth NiCu alloy on CeO2,the Ce0.9(Cu0.25Ni0.75)O2-? cathode shows the highest electrochemical performance,running for 100 hours continuously.The current density of electrolytic carbon dioxide(CO2)has almost no attenuation,showing perfect long-term performance.The electrochemical reduction performance of carbon dioxide(CO2)has been improved in a wide range of cathode materials(from metal based cathode to ceramic based catode)through the application of interface engineering.The active interface constructed of the functional and in situ growth nanoparticles,promotes the adsorption/activation of carbon dioxide(CO2).The interfacial structures of these nanoparticles with strong binding force also enhance the long-term performance of the materials.