二维NiFe-N_(x)-C催化剂的制备及电催化二氧化碳还原性能研究

Synthesis of 2D NiFe-N_(x)-C materials for electrocatalytic CO_(2)reduction

为降低碳基催化剂Ni-N位点上CO_(2)的活化能垒,并解决Fe-N位点上的CO中毒问题,以NaCl为模板,采用限制溶剂生长和热解法合成了具有NiFe-Nx双活性位点的超薄二维碳基催化剂(ZNF-900)。结果显示:ZNF-900具有超高的电催化CO_(2)还原生成CO的选择性(FECO>97%)和电流密度(j_(CO)=37.3 mA·cm^(-2))。通过XPS、Raman等表征和EIS、Tafel斜率等电化学分析方法,证明Ni和Fe之间存在协同促进作用,从而促进了催化剂表面CO_(2)分子的吸附和CO产物的脱附。

In order to reduce the energy barrier of CO_(2)activation at Ni-N sites and solve the problem of CO poisoning at Fe-N sites,an ultra-thin two-dimensional carbon-based catalyst(ZNF-900)with NiFe-Nx active sites was synthesized by limited solvent growth and pyrolysis methods.The ZNF-900 has ultra-high selectivity(FECO>97%)and CO partial current density(j_(CO)=37.3 mA·cm^(-2))for electrocatalytic CO_(2)reduction to CO.By XPS,Raman,EIS,Tafel slope and other analytic methods,it is proved that there is a synergistic promoting effect between Ni and Fe,which promotes the adsorption of CO_(2)mole-cules and the desorption of CO products on the surface of catalysts.