过渡金属-氮共掺杂炭基催化剂广泛应用于电催化二氧化碳还原反应（CO₂RR）。为解决催化剂存在的催化活性及选择性问题,以乙二胺与硝酸镍发生配位反应形成的三乙二胺合镍小分子络合物作为氮源和镍源,分别以亲水氧化石墨烯及疏水炭黑为载体,得到两类镍-氮共掺杂多孔炭基催化剂。通过X射线衍射及透射电镜等手段分析了镍物种在不同处理阶段的存在形式。CO₂RR性能测试表明,同一炭载体具有不同金属负载量的催化剂经过酸洗处理除去镍纳米颗粒后,一氧化碳分电流密度得到明显提升,表明原子级分散的镍物种是CO₂RR的活性位点。在-0.8 V（vs.RHE）,不同催化剂的一氧化碳法拉第效率均达到90%。与亲水炭材料作为载体相比,疏水炭材料为载体制备的催化剂一氧化碳分电流密度更高,这表明疏水炭载体有利于过渡金属络合物在载体骨架中的负载与分散,进而抑制后续处理过程中活性物质的损失,从而获得高活性的镍-氮共掺杂炭基电催化剂。

Transition metal-nitrogen co-doped carbon-based catalysts have attracted widely attention in electrocatalytic CO₂ reduction reaction（CO₂RR）.To solve the problems of catalytic activity and selectivity of catalysts,two kinds of Ni-N co-do-ped porous carbon-based catalysts were prepared by using triethylenediamine,a small molecule complex,formed by the coor-dination reaction between ethylenediamine and nickel nitrate and hydrophilic GO and hydrophobic carbon black were select-ed as the support,respectively.The existing forms of nickel species in different processing stages were discussed by X-ray diffraction and transmission electron microscopy.The CO₂RR performance showed that the CO current density had been enhanced when the catalyst with different metal loadings on the same carbon support was pickled to remove nickel nanoparticles,which indicated that the nickel species in high dispersion were beneficial to the electrocatalytic reduction of CO₂.At the potential of -0.8 V(vs.RHE),the catalysts with different carbon supports reached a CO Faradic efficiency of 90%.Compared with hydrophilic carbon materials as supports,hydrophobic carbon materials as supports had higher carbon monoxide partial current density,which indicated that hydrophobic carbon supports were conducive to the loading and dispersion of transition metal complexes in the framework of the support,and then inhibited the loss of active substances in the subsequent treatment process,so as to obtain high activity Ni-N co-doped carbon based electrocatalysts.