Organic-Polyoxometalate Co-Crystal-Derived Mesoporous Metal Carbides/Nitrides for Hydrogen Production from Seawater

本项目的目标是实现高Mo/W含量和结晶度的介孔金属碳化物/氮化物析氢反应(HER)催化剂的可规模合成。我们提出了一种新的沉淀法来合成有机-多金属氧酸盐(POM)共晶和有机-POM-二氧化硅复合材料，这些复合材料可以直接转化为介孔Mo/W碳化物/氮化物。在这些共晶结构中，POM保证了高的Mo/W含量，而不同的氨基官能化苯衍生物作为配位连接剂和碳/氮源。二氧化硅纳米颗粒将被添加作为模板，并在最终材料中产生介孔。在第一步中，我们将对有机聚甲醛晶体的结构和形貌进行充分的探索。此外，还将阐明所选择的合成条件对这些有机-聚甲醛-二氧化硅复合材料的形成和结构的影响。经过炭化和脱模板剂处理后，得到的介孔Mo/W碳化物/氮化物将首先在标准电解液中用作HER催化剂，然后应用于组装分水电解槽。总体而言，这一建议包含了几个研究目标，从选择合适的有机分子来获得有机-POM共晶并控制/优化其形态、组成和结晶度，到由其制备介孔Mo/W碳化物/氮化物，最后对这些材料进行电化学和电催化测试，以实现从海水中析氢。

The aim of this project is to achieve a scalable synthesis of mesoporous metal carbide/nitride-based hydrogen evolution reaction (HER) catalysts with high Mo/W content and crystallinity. We propose a novel precipitation method to synthesize organic-polyoxometallate (POM) co-crystals and organic-POM-silica composites which can be directly transferred into mesoporous Mo/W carbides/nitrides. In these co-crystal structures, the POM ensures a high Mo/W content while different amino-functionalized benzene derivatives serve as coordination linkers and carbon/nitrogen sources. Silica nanoparticles will be added to act as a template and generate mesoporosity in the final materials. In the first step, the structure and morphology of the organic-POM crystals will be fully explored. Furthermore, the influence of the chosen synthetic conditions on the formation and structure of these organic-POM-silica composites will be elucidated. After carbonization and template removal, the resulting mesoporous Mo/W carbides/nitrides will be applied as catalysts for HER first in standard electrolytes, and then applied to assemble water splitting electrolyzers. Overall, this proposal contains several research objectives starting from the selection of suitable organic molecules to obtain organic-POM co-crystals and controlling/optimizing their morphology, composition, and crystallinity, to the fabrication of mesoporous Mo/W carbide/nitrides therefrom, and finally electrochemical and electrocatalytic tests of these materials for water electrolysis with the specific objective to achieve hydrogen evolution from seawater.