以Mn(Ac)2和Co(Ac)2作为前驱体,导电碳Ketjenblack (KB)作为负载碳源,采用水解-水热法制备氮掺杂的MnCo2O4/N-KB催化剂材料,对其结构特征和碱性溶液中氧还原反应的催化性能进行表征,并进一步分析其氧还原反应活性。结果表明:MnCo2O4/N-KB催化剂的形态是KB骨架上生长纳米级MnCo2O4,并且在N-KB和MnCo2O4之间形成化学耦合,产生协同作用,有效提高了MnCo2O4/N-KB催化剂的氧还原活性。MnCo2O4与N-KB的质量比为1∶9时,MnCo2O4/N-KB催化剂在O2饱和0.1mol·L-1KOH溶液中对氧还原反应的电催化性能最佳,反应的极限电流密度为5.7 mA·cm-2,半波电位接近0.81 V,电子转移数为4。在相同负载量下,MnCo2O4/N-KB催化剂相比商用Pt/C(电流密度5.2 mA·cm-2,半波电位0.83 V)有着更高的极限电流密度和耐久性。
MnCo2O4/N-KB catalysts was prepared by hydrolysis-hydrothermal method,in which Mn(Ac)2 and Co(Ac)2 were used as precursors and nitrogen doped conductive carbon Ketjenblack(KB)was used as the carbon source.The microstructure of the MnCo2O4/N-KB catalysts and its catalytic performance for oxide reduction reaction were studied.The results showed that chemical coupling was formed between N-KB and MnCo2O4.It produced synergistic effect and effectively improved the oxygen reduction activity of MnCo2O4/N-KB catalyst.When the mass ratio of MnCo2O4 to N-KB was 1∶9,the limiting current density of the reaction was 5.7 mA·cm-2 and the half wave potential was close to 0.81 V.MnCo2O4/N-KB catalyst obtained the best electrocatalytic performance for oxygen reduction.Comparing to the commercial Pt/C catatlyst with a current density of 5.2 mA·cm-2 and a half-wave potential 0.83 V,MnCo2O4/N-KB catalyst had a highly active oxygen reduction with higher ultimate current density and durability under the same capacity condition.
Chinese Journal of Inorganic Chemistry
oxygen reduction reaction
manganese cobalt spinel