大孔碳载Ir催化剂对氨氧化的电催化性能

分别以大孔炭(MC)和Vulcan XC-72炭黑(XC)为载体，制备了Ir/MC和Ir/XC催化剂。 在用X射线能量色散谱(EDS)、X射线衍射(XRD)谱、拉曼光谱对催化剂表征的基础上，用电化学技术研究了2种炭载Ir催化剂对氨氧化的电催化性能，发现氨在Ir/MC催化剂电极上，氧化峰峰电流密度比在Ir/XC催化剂电极上大38.7%左右，而且电催化稳定性明显好于Ir/XC催化剂。 由于Ir/MC和Ir/XC催化剂的Ir粒子平均粒径和相对结晶度相似，因此，这只能归结于MC有大的孔径和孔率及高的石墨化程度引起的高电导率。 所以MC是一种比XC更好的催化剂的炭载体。

Electrocatalytic Performance of Ir Catalyst Supported on Macroporous Carbon for Ammonia Oxidation

Macroporous carbon supported Ir(Ir/MC) and Vulcan XC-72 carbon supported Ir(Ir/XC) catalysts were prepared respectively.Based on the characterization of the catalysts using the energy dispersive spectroscopy,X-ray diffraction spectroscopy and Raman spectroscopy,the electrocatalytic performances of the two catalysts for the ammonia oxidation were investigated.It was found that the peak current density of the ammonia oxidation at the Ir/MC catalyst electrode is 38.7% larger than that at the Ir/XC catalyst electrode and the electrocatalytic stability of the Ir/MC catalyst is better than that of the Ir/XC catalyst.Because the average size and the relative crystallinity of the Ir particles in the Ir/MC catalyst is similar to that in the Ir/XC catalyst,the above results can be attributed to the larger pore size and porosity as well as the higher conductivity due to the high graphitization extent of MC.