Fe-N-C材料是一类重要的电催化还原CO₂为CO的催化剂,但其只能在较正的电位和较窄的电位窗口实现CO的高选择性,不能满足串联催化中CO被进一步还原的要求。因此,以高纯Fe(phen)₃Cl₂(phen=1,10-邻菲罗啉)晶体和ZIF-8为前驱体,通过热解得到新颖的Fe-N-C担载γ-Fe₂O₃空心球材料。利用SEM、HR-TEM、XRD、XPS等对催化剂进行表征,并对其电催化还原CO₂的性能进行测试。结果表明,该催化剂在-0.5~-1.1 V(相对于可逆氢电极)宽电位窗口表现出优异的CO选择性(CO的法拉第效率大于97%),且在-0.6 V连续电解2h后电流密度和CO的法拉第效率均基本保持不变,表现出卓越的稳定性。

Fe-N-C materials are promising catalysts for the electroreduction of CO₂ to CO,but they can achieve high CO selectivity only at relatively positive potentials and within a narrow potential window,which does not meet the requirement for the further reduction of CO in tandem catalysis.A novel γ-Fe₂O₃ hollow spheres dispersed on Fe-N-C materials are obtained through the pyrolysis of Fe(phen)₃Cl₂ crystals and ZIF-8.These materials are characterized by means of SEM,HR-TEM,XRD,XPS,etc.,and their performance are tested as the catalyst in electrocatalysis reduction of carbon dioxide.It is verified that the catalyst exhibits excellent CO selectivity with the faradaic efficiency (FE_CO) exceeding 97% over a broad potential window ranging from -0.5V to -1.1V vs.reversible hydrogen electrode.The catalyst can maintain its current density and FE_CO after the electrolysis has been performed at -0.6V for 2 h,showing outstanding stability.

聂邓根(1997-),男,硕士生,研究方向为电催化CO₂还原,1606105345@qq.com;郭振国(1988-),男,博士,副研究员,硕士生导师,研究方向为电催化和光催化CO₂还原,通讯联系人,gzg2020@hfut.edu.cn。