高温热裂解电催化剂Ketjen Black EC300J碳黑负载钴卟啉的氧还原性能

选用具有高介孔表面积和高导电性能的碳黑Ketjen Black EC 300J(简称KB)作为载体,制备了碳黑负载钴卟啉(CoTMPP/KB),经过900℃热处理后得到电催化剂,用于燃料电池阴极氧还原反应.利用循环伏安法(CV)研究了碳载体不同预处理方法以及高温热处理对碳黑负载钴卟啉电催化剂的氧还原催化性能的影响.结果...

High-temperature Pyrolysis of Ketjen Black EC 300J Supported Cobalt Porphyrin Complexes as Electrocatalysis for Oxygen Reduction

Carbon black EC 300J (KB) with high mesoporous area and electrical conductivity was used as support for cobalt tetramethoxyphenylporphyrin (CoTMPP) to prepare the cathode electrocatalysts (CoTMPP/KB) for the oxygen reduction in proton exchange membrane fuel cell (PEMFC). The influence of chemical pretreatment of carbon black supports and 900 ℃ heat-treating of the electrocatalysts on the electrocatalytic activities for oxygen reduction of CoTMPP/KB were investigated by cyclic voltammogram (CV). Results show that with 6 mol?L-1 HNO3 pretreatment of carbon support and 900 ℃ heat-treatment of the catalyst, although the pyrolysis occurred for the CoTMPP structure, the electrocatalyst shows the best catalytic performance for oxygen reduction, both the cathodic peak potential ( Ep ) and the maximum capacitive current ( Ip ) have been improved. The surface properties and the microstructures of both the carbon black KB and the electrocatalyst have been investigated by IR, XRD, TEM and nitrogen adsorption/desorption. After the pretreatment with 6 mol?L-1 HNO3, the concentration of hydroxyl group and other oxygen-groups has been increased on KB surface and no obvious particle aggregation of KB has been observed, an average particle size of about 30 nm of KB has been observed; The pore structure of the catalysts is mainly composed of mesopores and has a narrow pore size distribution, which prove CoTMPP/KB to be a good electrocatalyst; CoC3 (101) and metallic Co(111) have been formed in the catalyst after 900 ℃ heat-treatment, and the cobalt ions have been well dispersed in the carbon black surface, with mean pore size of 8.2 nm and surface area of 463.4 m2?g-1.