High efficiency of Pt2+ - CeO2 novel thin film catalyst as anode for proton exchange membrane fuel cells

The elevated price of Pt limits the large-scale implementation of commercial proton exchange membrane fuel cells, which effectively convert chemical energy into electricity. In order to increase the cost-efficiency in proton-exchange membrane fuel cells, we have designed a family of novel anode catalysts consisting of thin films of ceria with low Pt loadings sputtered on a nanostructured carbon support. Remarkably, only such small amounts of Pt are necessary for achieving power density values comparable to the reference commercial catalysts, which results in excellent specific activities of our samples. By combining photoelectron spectroscopy and catalytic performance analysis, we have shown that the surface Pt2+ species in cerium oxide exhibit high electrocatalytic activity. Density functional theory calculations show that the great stability of Pt2+ species on ceria makes these resistant to reduction by hydrogenation and suggests that the formation of such stable surface complexes prevents degradation of the nanostructured composite. (C) 2016 Elsevier B.V. All rights reserved.