Electrochemical carbon dioxide reduction reaction (CO₂RR) provides a promising pathway for both decreasing atmospheric CO₂ concentration and producing valuable carbon‐based fuels. To explore efficient and cost‐effective catalysts for electrochemical CO₂RR is of great importance, but remains challenging. Se‐doped carbon nanosheets (Se‐CNs) with a micro‐, meso‐, and macroporous structure are proposed for electrochemical CO₂RR. Such an electrocatalyst combines the advantages of Se optimized active sites, hierarchical pores for facilitating reactant or ion penetration, transport and reaction, and large surface area for more accessible active sites. This Se‐CNs electrocatalyst exhibits over 11‐times enhanced partial current density of CO than the CNs without Se doping and high selectivity (90%) for CO₂ electroreduction to CO at a low potential of −0.6 V versus the reversible hydrogen electrode (vs RHE). Density function theoretical calculations reveal that the Se introduction in CNs lowers the free energy barrier of CO₂RR and inhibits hydrogen evolution reaction effectively, thus improving the selectivity for CO₂ reduction to CO. This work presents a new member of the metal‐free electrocatalyst family, which is easily prepared, low cost, adjustable, and highly efficient for CO₂RR.

中文翻译：

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硒掺杂的层状多孔碳纳米片作为一种有效的无金属电催化剂，可减少二氧化碳排放

电化学二氧化碳还原反应（CO ₂ RR）为降低大气中CO ₂浓度和生产有价值的碳基燃料提供了有希望的途径。探索用于电化学CO ₂ RR的高效且具有成本效益的催化剂非常重要，但仍具有挑战性。提出了具有微孔，中孔和大孔结构的硒掺杂碳纳米片（Se-CNs）用于电化学CO ₂RR。这种电催化剂结合了Se优化的活性位点，便于反应物或离子渗透，传输和反应的分层孔以及更大的表面积（更易于访问的活性位点）的优点。这种Se-CNs电催化剂比未掺杂Se的CNs表现出的CO局部电流密度提高11倍以上，相对于可逆氢电极（vs ），在低电位-0.6 V时，CO ₂电还原为CO的选择性高（90％）RHE）。密度泛函理论计算表明，CNs中Se的引入降低了CO ₂ RR的自由能垒，有效抑制了氢的析出反应，从而提高了对CO ₂的选择性。这项工作提出了一种无金属的电催化剂家族的新成员，它易于制备，成本低，可调节且对CO ₂ RR高效。