纳米金电催化还原CO2的载体效应

Support Effect of Nano-gold Electrocatalytic Reduction of CO

通过化学还原法制备得到了不同载体(碳纳米管(CNT)、炭黑(CB)、石墨碳(GC)、介孔碳(MC))负载的纳米Au催化剂,研究了载体对纳米Au电催化还原CO2的影响。Au/CNT和Au/CB催化剂的载体具有较大比表面积,分别为90.1、81.5 m2/g,并且载体与纳米Au之间具有强结合能。4种催化剂电催化还原CO2的性能结果显示,Au/CB催化剂具有更好的稳定性,28 h的稳定性测试中,CO的法拉第效率(FE)仅下降5%;Au/CNT催化剂的催化活性和选择性最高,起始电压仅为-0.4 V,且此时还原产物CO的法拉第效率约为100%。相比较之下,Au/GC和Au/MC催化剂上CO2反应活性低和选择性差,在稳定性测试中对CO的选择性都降为0。

Nano Au catalysts supported on carbon nanotubes(CNT),carbon black(CB),graphite carbon(GC)and mesoporous carbon(MC)were prepared by chemical reduction method.The effect of the support on the nano-Au electrocatalytic reduction of CO2 was explored.The supports of Au/CNT and Au/CB catalysts have large specific surface areas of 90.1,81.5 m2/g,respectively,with strong binding energy between the support and nano-Au.The performance results of four catalysts for electrocatalytic reduction of CO2 show that Au/CB catalyst has better stability.In the 28-hour stability test,the Faraday efficiency of CO decreased by only 5%.Au/CNT catalyst has the highest catalytic activity and selectivity.The initial voltage is only-0.4 V,and the Faraday efficiency of the reduction product CO is about 100%.In comparison,the Au/GC and Au/MC catalysts have low CO2 reactivity and poor selectivity,and the selectivity to CO in stability tests was reduced to zero.