Abstract
The potential of formic acid as hydrogen sources in fuel cell has received considerable attention, due to its low temperature operation and shown higher efficiencies than other alcohol based fuel cells. Formic acid decomposition then plays an important role in a formic acid fuel cells. Experimentally, it was reported that the formic acid adsorbs and decomposes as formate on Cu(110) at room temperature. While, decomposition does not take place at room temperature on the close-packed surface of Cu(111). On Cu(111) surface, formic acid forms polymeric structure at low temperature, in which the hydrogen bonding network has a role to stabilizes the adsorption. Many theoretical study have been done to investigate single molecule HCOOH adsorption and decomposition on transition metal surfaces. However, the detail mechanism of HCOOH decomposition from polymeric structures is still obscure. Therefore, we investigate the mechanism of HCOOH decomposition from polymeric structures by means density functional study. The formic acid decomposition is evaluated in monomer, -chain and -chain case. Desorption and decomposition process of formic acid are through the HCOO-mediated pathways. The polymeric structure of formic acid stabilizes the formic acid adsorption on Cu surface. We also observe the decomposition process take place at the edge of the polymer rather than middle part of perfect polymer chains.
