电化学中和能辅助碱-酸电解池节能制氢

Hydrogen generation via water electrolysis is highly desirable but remains great issues of high energy consumption and high cost. The project proposed an asymmetric-electrolyte alkaline acidic cell, in which the chamber of the anode and the cathode were separated by bipolar membrane, targeting to developing a low-cost and energy-saving electrolyzer system. With the as-proposed cell, the electrochemical neutralization energy can be harvested to assist water electrolysis with decreasing the electrical energy required. In addition, the bifunctional electrocatalyst will be rationally designed and functionalized to optimize the electrocatalytic performance toward hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), in the hope to cut down the overpotential of both half reactions involved in water electrolysis. The structure-performance relationship will be also investigated by characterizing the as-designed electrocatalysts and testing their electrochemical properties and mechanism for optimizing the catalytic performance of HER and OER. The project will provide us with idea to address the big issue (high energy consumed) and is thus of great significance to the fundamental research in the fields of water electrolysis.

针对电解水制氢过程耗能大、成本高的基础科学问题，本项目申请提出通过构建由双功能催化剂电极组装的碱-酸不对称电解液电池，一方面，通过构建由双极膜隔离阳极和阴极的碱-酸电解池，可以捕获电化学中和能以协助电解水过程，减少电解水制氢过程的能耗；另一方面，通过合理的合成设计和功能化，开发在酸性溶液中对析氢反应和碱性电解液中对析氧反应具有优异催化性能的低成本高稳定性的双功能催化剂电极，以降低电解水过程中两个半反应的过电势。通过研究材料结构、形貌、组分与其催化性能与机理的构效关系，优化碱性析氧反应和酸性析氢反应的催化性能，为解决电解水制氢存在的耗能高问题提供有意义的基础科学研究。

针对电解水制氢过程耗能大、成本高的基础科学问题，项目根据申请书的研究内容，研发了系列对酸性介质阴极析氢反应和碱性介质阳极氧化反应具有优异电催化性能的双功能电极，并以此开发了具有酸性阴极液和碱性阳极液的双电解液混合电化学池，一方面，通过合理设计并结合不同合成方法，制备了在酸性溶液中对析氢反应和碱性电解液中阳极氧化反应具有优异催化性能的低成本双功能催化剂，并通过优化材料结构、形貌、组分提高相应催化性能，降低电解制氢过程中两个半反应的过电势；另一方面，通过构建由酸阴极液/碱阳极液的双电解液混合电解池，利用电化学中和能协助电解过程，显著减少了制氢过程的电耗。项目的完成不仅为发展新型电化学制氢技术提供借鉴，也为解决电解制氢过程等关键问题提供参考。