Abstract: In past decades，more intensive researches have been focused on the development of non-noble-metal catalysts for oxygen reduction reaction (ORR) in fuel cells in order to replace the Pt-based catalyst with high cost and scarcity，as fuel cells were recognized as one of the most promising power sources due to their high efficiency and low emissions. In present work，a natural polymer，chitosan (CS)，was reacted with salicylaldehyde to produce chitosan salicylaldehyde schiff-base (CS-Sal)，which then chelated with iron salt to obtain Fe complexes of chitosan salicylaldehyde schiff-base (Fe-CS-Sal). Subsequently，Fe-CS-Sal was mixed with high pure graphite and fully grinded with pestle in a mortar for homogeneous mixing to obtain carbon supported iron complex Fe-CS-Sal/C. Then，the resulting Fe-CS-Sal/C was heat-treated at different temperatures under N2 atmosphere getting a series of Fe-N-C-t (t= 200℃，400℃，600℃，800℃，1000℃) catalysts. Cyclic voltammetry (CV) and chronocoulometry (CC) in electrochemical workstation were used to study electrocatalytic performance of the Fe-N-C-t catalysts for oxygen reduction reaction (ORR). FT-IR and XRD were used to characterize the structure of Fe-N-C-t catalyst with different electrocatalytic activity to ORR. The ORR reaction kinetic parameters were further calculated according to cyclic voltammetry and the possible ORR mechanism occurring with the Fe-N-C-t catalysts was proposed in this paper.

Key words: heat treatment, Fe-N-C-T, electrocatalysis, oxygen reduction, kinetics, heat treatment, Fe-N-C-t, electrochemistry, catalysts, oxygen reduction, kinetics

摘要： 选用天然高分子化合物壳聚糖（CS）与水杨醛（salicylaldehyde）反应生成壳聚糖水杨醛席夫碱（CS-Sal），CS-Sal又与过渡金属Fe盐发生螯合反应，得到壳聚糖水杨醛席夫碱Fe配合物（Fe-CS-Sal）。将Fe-CS-Sal负载于活化的高纯石墨上，在N2氛围中进行不同温度的热处理，得到系列催化剂Fe-N-C-t（t=200℃，400℃，600℃，800℃，1000℃）。运用循环伏安法（CV）、计时库仑法（CC）研究了Fe-N-C-t催化剂电催化氧还原反应（ORR）的催化性能，并结合FT-IR、XRD结构表征，探索了Fe-N-C-t催化剂电催化ORR的催化活性位。结果表明，催化剂Fe-N-C-1000对ORR的电催化活性最好。同时根据循环伏安法和计时电流法计算得出ORR的动力学参数，提出了在此催化剂上可能发生的ORR的催化机理。

关键词: 热处理, Fe-N-C-t, 电催化, 氧还原, 动力学, 热处理, Fe-N-C-t, 电化学, 催化剂, 氧还原, 动力学