HCOOH decomposition on Pt(111): A DFT study

SURFACE SCIENCE

卷:648

Article

Scaranto, Jessica¹  Mavrikakis, Manos¹ 

[1] Univ Wisconsin, Dept Chem & Biol Engn, 1415 Engn Dr, Madison, WI 53706 USA

关键词: Pt(111);    Formic acid;    Decomposition;    Formate;    Carboxyl;    Density functional theory;   

DOI  :  10.1016/j.susc.2015.09.023

来源: Elsevier

【 摘 要 】

Formic acid (HCOOH) decomposition on transition metal surfaces is important for hydrogen production and for its electro-oxidation in direct HCOOH fuel cells. HCOOH can decompose through dehydrogenation leading to formation of CO2 and H-2 or dehydration leading to CO and H2O; because CO can poison metal surfaces, dehydrogenation is typically the desirable decomposition path. Here we report a mechanistic analysis of HCOOH decomposition on Pt(111), obtained from a plane wave density functional theory (DFT-PW91) study. We analyzed the dehydrogenation mechanism by considering the two possible pathways involving the formate (HCOO) or the carboxyl (COOH) intermediate. We also considered several possible dehydration paths leading to CO formation. We studied HCOO and COOH decomposition both on the dean surface and in the presence of other relevant co-adsorbates. The results suggest that COOH formation is energetically more difficult than HCOO formation. In contrast, COOH dehydrogenation is easier than HCOO decomposition. We found that CO2 is the main product through both pathways and that CO is produced mainly through the dehydroxylation of the COOH intermediate. (C) 2015 Elsevier B.V. All rights reserved.

【 授权许可】

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