Electrocatalyst synthesized from metal organic frameworks

Pt nanoparticles as the common electrocatalyst for proton exchange membrane fuel cells (PEMFCs) were prepared for the first time from metal organic frameworks (MOFs). Pt containing MOF was synthesized and subsequently subjected to pyrolytic carbonization under non-reactive gas atmosphere. Upon pyrolysis, Pt nanoparticles embedded in electronically conductive carbon media were produced. The assynthesized MOF materials and the prepared electrocatalysts were characterized by XRD, N-2 physisorption, TEM and XPS. The Pt dispersion of obtained electrocatalysts was determined by hydrogen chemisorption. Their conductivity was measured by impedance spectroscopy. The membrane-electrode assemblies (MEAs) made of these electrocatalysts were tested as both anode and cathode in a H-2/air single cell fuel cell. As the anode, the most promising electrocatalyst (C-3) demonstrated an open circuit voltage of 970 mV and power density of 0.58 W mg(Pt)(-1) comparable to the commercial electrode power density (0.64 W mg(Pt)(-1)) at 0.6 V in a single cell test. At the cathode, a power density of 0.38 W mg(Pt)(-1) at 0.6 V was achieved. This confirms the promising potential of this simple approach to be used as a technique to prepare efficient fuel cell electrocatalysts. (C) 2013 Elsevier B.V. All rights reserved.