Fe-Co-N-C氧还原催化剂的制备及性能

Synthesis and Properties of Fe-Co-N-C Catalysts for Oxygen Reduction Reaction

为了提高氮掺杂碳(N-C)材料的氧还原性能,采用后吸附法基于可在高温炭化过程中形成富缺陷碳材料及均匀分散的高活性M-N_(x)位点的沸石咪唑酯骨架-8衍生制备了Fe-Co-N-C催化剂。电化学测试结果表明采用150 mg Co-N-C催化剂吸附0.07 mmol Fe制备的Fe-Co-N-C催化剂在0.1 mol/L HClO_(4)中具有较高的半波电位(0.843 V vs. RHE)和较低的过氧化氢产率(<4%)。物性表征结果表明Fe-Co-N-C催化剂的优异氧还原活性可归因于其双金属活性位点(Fe/Co-N_(x))、丰富的微/介孔结构、较高的石墨化程度以及Fe/Fe_(3)C和Fe-N_(x)的共同作用。

To improve the oxygen reduction performance of nitrogen-doped carbon(N-C)material,a post-adsorption method was used based on zeolite imidazolate framework-8(ZIF-8)that can form defect-rich carbon materials and uniformly dispersed and highly active M-N_(x) sites during high-temperature carbonization,and ZIF-8-derived Fe-Co-N-C catalysts were synthesized.Electrochemical characterizations show that the Fe-Co-N-C catalyst derived from 150 mg of Co-N-C adsorbing 0.07 mmol of Fe(acac)_(3) has the largest half wave potential of 0.843 V vs.oxygen reduction reaction in 0.1 mol/L of HClO 4,and a low hydrogen peroxide yield(<4%).Physicochemical characterization indicates that the high oxygen reduction reaction activity of Fe-Co-N-C can be attributed to its bimetallic active site(Fe/Co-N_(x)),rich micro/mesoporous structure,high degree of graphitization,and the collective effectof Fe/Fe_(3)C and Fe-N_(x).