Electrochemical reduction of CO2 into high value-added products is currently the effective strategy to mitigate global warming and energy storage conversion. Unfortunately, the lower selectivity, activity, and stability of electrocatalysts have been the biggest obstacle to further development. The Ni–N-doped ordered porous carbon material, which shows a unique structure and high surface area, has an excellent CO2 reduction reaction (CO2RR) activity and can also inhibit its competitive reaction-hydrogen evolution reaction (HER). Herein, we apply a simple dual-templating strategy to synthesize Ni–N-doped three-dimensional ordered macro-/mesoporous carbons (Ni–N-OMMCs) and investigate the CO2RR performance of Ni–N-OMMCs from precursors with different Ni amounts. The optimum catalyst (Ni–N-OMMC-0.6) exhibits excellent electrocatalytic activity with a maximum Faradaic efficiency of ∼98% for CO formation at −0.7 V vs the reversible hydrogen electrode (RHE) and shows a wide potential range from −0.65 to −1.0 V with a Faradaic efficiency of over 60%. In addition, after a 25 h stability test, the activity of the catalyst is only attenuated by 5.6%. This study demonstrates a promising strategy for preparing highly efficient catalysts for CO2RR.

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穆春辉 a 张艺馨 a 寇伟 a 徐联宾 * ,a,b ( a 北京化工大学有机无机复合材料国家重点实验室 北京 100029) ( b 北京化工大学教育部超重力工程研究中心 北京 100029) 摘要 多组分体系中的协同作用为设计高效的二氧化碳还原电催化剂提供了新的思路. 本工作通过双模板法和化学还 原法精心设计制备了大孔/介孔镍氮掺杂碳(Ni-N-OMMC)负载银纳米颗粒复合材料(Ag/Ni-N-OMMC), 用于高效电催化 还原 CO2为 CO. 此复合材料表现出良好的电催化活性, 在 CO2 饱和的 0.1 mol•L -1 KHCO3 电解液中, 电位为-1.0 V (相 对于可逆氢电极, RHE)时 CO 的电流密度(JCO)高达 33.29 mA•cm -2 . 并具有较宽的工作电压范围, 在-0.7～-1.0 V (vs. RHE)下, CO 的法拉第效率超过 90%. 其优异的电催化性能可能归因于 Ag 纳米颗粒与具有丰富 Ni-Nx 活性位点的 Ni-N-OMMC 载体之间的协同效应, 以及三维互联有序大孔/介孔结构提供的高比表面积和高效的质量/电荷传输.