A DFT study on PtMo resistance to SO_2 poisoning  

作　　者：XIA MeiRong LIU Ying LI Li XIONG Kun QI XueQiang YANG LinJiang HU BaoShan XUE Yun WEI ZiDong 

机构地区：[1]The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Chemistry and Chemical Engineering, Chongqing University

出　　处：《Science China Chemistry》2013年第7期1004-1008,共5页中国科学（化学英文版）

基　　金：financially supported by the National Basic Research Program of China (973 Program, 2012CB215500, 2012CB720300);the National Natural Science Foundation of China (51072239, 20936008);the Fundamental Research Funds for the Central Universities (CDJZR-12228802)

摘　　要：Pt is a catalyst in proton exchange membrane fuel cell （PEMFC）, and its activity will be degraded in the air due to the exist- ence of SOx impurities. On strategy is introducing of Mo into the Pt catalyst because it can improve the SOx-tolerance capacity. Based on the aforementioned phenomenon, a density function theory （DFT） study on SOx adsorbed on Pt（111） and PtMo（111） was performed to enhance Pt catalytic activity. The adsorption energy of adsorbed species, the net change, partial density of state （PDOS）, and d-band center were calculated and analyzed comparatively. The results show that the presence of Mo-atom weakens the S-Pt bond strength and reduces the adsorption energies for SO2, S and SO3 on PtMo（111）. Moreover, the Mo atom weakens the effects of SO2 on the PtMo（lll） electronic structure and makes the catalyst maintains its original electronic structure after SO2 adsorption as compared with Pt（111）.Pt is a catalyst in proton exchange membrane fuel cell (PEMFC), and its activity will be degraded in the air due to the existence of SOx impurities. On strategy is introducing of Mo into the Pt catalyst because it can improve the SOx -tolerance capacity. Based on the aforementioned phenomenon, a density function theory (DFT) study on SO x adsorbed on Pt(111) and PtMo(111) was performed to enhance Pt catalytic activity. The adsorption energy of adsorbed species, the net change, partial density of state (PDOS), and d-band center were calculated and analyzed comparatively. The results show that the presence of Mo-atom weakens the S-Pt bond strength and reduces the adsorption energies for SO2 , S and SO3 on PtMo(111). Moreover, the Mo atom weakens the effects of SO2 on the PtMo(111) electronic structure and makes the catalyst maintains its original electronic structure after SO2 adsorption as compared with Pt(111).

关 键 词：density functional theory SO2 Pt PTMO partial density of states fuel cells ELECTROCATALYSIS 

分 类 号：O643.36[理学—物理化学]