多酸为母体在碳载体上可控生长双金属氧化物用于电催化还原CO2

The electroreduction of carbon dioxide has many advantages, such as mild reaction conditions, strong controllability of processes, but the preparation of CO2 reduction catalysts with high conversion and selectivity is still a big challenge. Based on improving the efficiency of conversion from CO2 and selectivity, this project proposes the controllable preparation of bimetallic oxides assembled from polyoxometalates as precursors loading on carbon carriers for electrocatalytic CO2 reduction. The combination of two kinds of metal oxides and carbon carrier will generate the synergetic effect, which enhances the catalytic activities. Polyoxometalates are easy to coordinate with transition metals forming bimetallic clusters due to their high negative charge, which will enhance the effective contact between the two types of metals and regulate the proportion of the metals at the atomic level. Then the bimetallic clusters will be anchored on carbon carriers through coupling agents, and futher be transformed into small-sized bimetallic oxides/carbon complexes. Adjusting the structures, types, the numbers of vacancies of polyoxometalates, and the types of transition-metals, will regulate the proportion and valence of the metals at the atomic level, to further modulate the conversion and selectivity. The electrocatalytic performance for CO2 reduction reaction will be tested by using cyclic voltammetry and AC impedance technique. The theoretical simulation methods are applied to investigate the mechanism of electroreduction of CO2. The relationship between the structure and electrochemical performance will be explored and comprehend, which provides the experimental basis and theoretical support for the future development of non-noble metal catalysts with highly efficient for electrochemical reduction of CO2.

电催化还原CO2具有反应条件温和、过程可控等优势，但制备具有高转化率和选择性的CO2还原电催化剂依然是挑战。本项目立足提高转化率和选择性，提出多酸为母体制备双金属氧化物/碳复合材料用于电催化还原CO2的构想，利用其结合两种金属氧化物及碳载体的优势，充分发挥协同催化效应。利用多酸具有高负电荷易与过渡金属形成双金属簇合物，增强金属间的接触，通过偶联剂将此类簇锚定在碳载体上，进一步转化获得小尺寸双金属氧化物/碳复合体。改变多酸种类、结构、缺位度及过渡金属种类，可以从原子水平控制金属比例和价态，进而调控催化还原CO2转化率和选择性。结合多种手段研究材料微观结构及组分间相互作用。采用循环伏安、交流阻抗等研究材料对CO2还原反应电催化性能。采用理论模拟方法探究CO2电催化还原机制。理解催化剂结构、界面作用、表面性质与催化性能间的关系，为今后开发高效电化学还原CO2非贵金属催化剂提供实验依据和理论支持。

电催化还原CO2具有反应条件温和、过程可控等优势，但制备具有高转化率和选择性的CO2还原电催化剂依然是挑战。本项目提出多酸为母体制备双金属化合物/碳复合材料用于电催化还原CO2的构想，利用其结合两种金属化合化物及碳载体的优势，充分发挥协同催化效应。利用多酸具有高负电荷易与过渡金属形成双金属簇合物，增强金属间的接触，通过偶联剂将此类簇锚定在碳载体上，进一步转化获得小尺寸双金属氧化物/碳复合体。通过改变多酸的种类、结构和缺位度，调节过渡金属的种类，我们获得了一系列的以钨（钼、钒）基多酸为前驱体制备的双金属复合材料，并进行了相应的性能测试，我们发现控制粒子的尺寸、调控表面性质、构建异质界面等等有利于提高催化反应活性。在本项目资助下发表SCI研究论文15篇，其中由1篇论文被选为杂志的封面论文，为多金属氧酸盐化学在材料和能源领域的应用提供材料和实验数据。