陶瓷电极新型界面构筑及电重整CH4/CO2制合成气研究

Dry reforming of CH4/CO2 is an effective approach to for its utilization which has attracted wide attentions because of the potential application. However, the carbon deposition on metal catalysts from CO disproportionation reaction and CH4 thermal splitting as well as the sintering of nanocatalysts together cause performance degradation of dry reforming process. In this proposal, we aim to develop a novel process of electrochemical reforming CH4/CO2 in a solid oxide electrolysis cell in which the CO2 electrolysis is performed in cathode while the electrochemical oxidation of CH4 is simultaneously conducted in anode. We utilize the exsolution of metal-oxide interface to construct Ni1-zCuz/Nb2-xTixO4 composite electrodes and enhance the catalysis activity, coking resistance and high temperature stability. We will investigate the synergy of interface catalysis and external field to enhance the catalysis for CO2/CH4 reforming. We then study the correlation between interface architecture, interface compositions as well as the local electronic states and its influence to the reforming reactions. We finally investigate the electrochemical process of reforming of CH4/CO2 and the correlation of CH4/CO2, product selectivity, stability and cycling performances with the parameters including electrode microstructures, applied voltages and operation temperatures will also be studied. This project aims to demonstrate the construction of composite electrodes and the electrochemical reforming of CH4/CO2 into syngas, which will provide useful information for the natural gas utilization.

CH4/CO2干重整是天然气利用的有效途径，具有重要研究价值和应用前景。然而，金属催化剂由于高温CO歧化反应和CH4热裂解易积碳和烧结，会导致干重整性能衰减。本项目拟在固体氧化物电解池阴极电解CO2并同步在阳极电催化氧化CH4实现电化学重整CH4/CO2制合成气的新过程，并通过原位构筑铆合型Ni1-zCuz合金/Nb2-xTixO4金属-氧化物界面体系增强催化性能、抗积碳和稳定性。研究界面催化与外场的协同调控实现CH4向合成气直接转化对C和H原子利用率的增强机制。研究铆合型界面催化裂解CO2和CH4的机制及其与界面局域电子态的关联；研究界面结构和界面化学态对对抗积碳和稳定性的增强作用；研究电化学重整CH4/CO2制合成气的转化率、产物选择性、稳定性和循环性能对界面体系和外场如电压和温度的依赖关系。本项目拟阐明复合电极构筑及电化学重整CH4/CO2的机制，为开发利用天然气提供有价值的参考。

CH4/CO2干重整是天然气高效利用的有效途径，具有重要研究价值和应用前景。然而，金属催化剂由于CO歧化反应和CH4热裂解的积碳，以及纳米金属烧结问题，会导致干重整性能衰减。申请人制备了高性能固体氧化物电解池，分别以CO2和CH4为阴极和阳极反应物，实现了电化学重整CH4/CO2制合成气的新过程。申请人通过原位脱溶析出策略构筑了铆合型金属-氧化物界面新体系，这些新型界面结构构筑增强了抗积碳性能和高温稳定性，尤其是有助于作为三相界面显著提升了氧传输动力学。申请人通过关联电极材料的氧非化学计量比与界面活性的关系，揭示了阴极中氧空位形成及对CO2吸附活化与电催化裂解的增强机制，明确了阳极中活性氧通量对CH4活化与定向转化制合成气的强化机制。申请人通过协同调控温度场和电场，实现了CH4/CO2向合成气的高效转化，不仅为复合电极构筑提供了新方法，也对CH4/CO2的高效转化提供了新路径，为开发利用天然气提供有价值的参考。