CO2/H2O电化学重整转化制取合成气阵列电极的构建及基础研究

Synthesis gas fuel produced efficiently by CO2/H2O co-electrolysis of Solid Oxide Electrolysis Cell coupling carbon-free energy is a research focus in the fields both new energy and CCU(carbon dioxide capture and utilization). Electrodes of current Solid Oxide Electrolysis Cell are composed of disordering porous ceramic composite, there exists the key scientific problems of strong electrochemical polarization, strong concentration polarization and short life while CO2/H2O co-electrolysis. Aiming at the key scientific problems, the proposal brings forward new structure concept and preparation method of array ceramic nanorods electrode whose mass transfer channels of electron, oxygen ion and gases are highly ordering, moreover, the research of structure building and controllable preparation of array nanorods with characteristics of ordering oxygen ion conduction, controllable preparation and structure-activity relationship of nano catalyst layer, electrochemical model of ordering membrane electrode assembly, and electrochemistry behavior of CO2/H2O co-electrolysis in single Solid Oxide Electrolysis Cell will be carried out in this work. The results of building a new strucure solid oxide electrolysis cell with controllable array three-dimensional network mass transfer structure of oxygen ion, electron and gases, clarifying the oxygen ion conduction rule in array nanorods, developing electrochemical model of the electrode, explaining the quantitative relationship between electrode catalytic dynamic and microstructure, and revealing evolution of performance and structure for array nanorods are be expected. The theory and method for preparation of high performance ordering ceramic membrane electrode of Solid Oxide Electrolysis Cell will be gained by the project implementation, which is a foundation for application of the high temperature and high performance CO2/H2O co-electrolysis.

固体氧化物电解池耦合无碳能源将CO2/H2O高效电化学重整制取合成气燃料，是目前CO2转化利用领域的研究热点。现有固体氧化物电解池的电极为无序化的多孔复合陶瓷结构，存在电极强极化能耗高、原料气转化率低以及短寿命的关键科学问题。本申请提出电子、氧离子和气体多相传质高度有序化的阵列陶瓷电极的新体系及其基础研究，主要开展阵列YSZ纳米棒的生长机理与有序化氧离子导体可控制备、纳米催化剂层的调控与构效关系、有序化膜电极催化反应机理以及CO2/H2O共电解电化学行为研究。预期构建出低能耗、高转化率和长寿命的固体氧化物电解池新体系与理论基础。实现电极的多相传质三维网络微结构有序化；阐明阵列纳米棒电极的荷电输运机制，以及催化动力学与有序结构的定量关系；揭示阵列纳米棒微结构与性能的长期演变规律。该项目实施将创新高性能有序化陶瓷膜电极制备理论和方法，为CO2/H2O高效稳定共电解提供科学基础和技术支撑。

固体氧化物电解池耦合无碳能源将CO2/H2O高效电化学重整制取合成气燃料，是目前CO2转化利用领域的研究热点。现有固体氧化物电解池的电极为无序化的多孔复合陶瓷结构，存在电极强极化能耗高、原料气转化率低以及短寿命的关键科学问题。.针对上述科学问题，本项目提出了简化CO2/H2O 高温共电解电极的几何结构新思路，并成功制备出阵列YSZ纳米棒电极以及由其构成的SOEC电解池新体系。主要开展了阵列YSZ纳米棒||致密YSZ层||阵列YSZ纳米棒一体化新结构的构建，纳米催化剂的浸渍制备与优化，有序阵列SOEC膜电极的制备研究；并开展了阵列纳米催化剂层的调控与其电化学行为，有序化阵列膜电极的电化学模型，SOEC单体共电解性能研究。.项目主要成果为：1）通过利用溶胶凝胶法－模板法的联用，构建出了阵列YSZ纳米棒基体，并采用负压浸渍法制备出了阵列纳米棒电极，形成纳米Ni颗粒包覆YSZ纳米棒的阴极和LSM包覆YSZ 纳米棒的阳极新型SOEC有序化膜电极。实现了电极的氧离子、电子、气体通道的三维网络结构定向、可控设计；2）通过纳米催化剂在纳米棒表面上的生长，催化剂的成相浸渍量等微结构和相结构特性与溶液浓度等的定量研究, 揭示了阵列纳米棒微结构与CO2/H2O高温电化学重整性能的构效关系。在800 oC下，阳极不通入气体，阴极通入500m L/min湿度为90%的混合气体(氢气:CO2=10：1)，电流密度为0.323 A/cm时，系统效率高达到80.8%。在性能上全面优于传统SOEC膜电极；3）发表了SCI收录论文14篇，论文引用39次；申请了中国发明专利12件；培养了博士后一名、研究生3名。.该项目成果破解了制约CO2/H2O 共电解强电化学极化、强浓差极化、原料气转化率低以及短寿命的科学问题，带动了下一代有序化陶瓷膜电极的制备技术发展，为CO2/H2O高效电化学重整制取合成气应用奠定了理论和技术基础。