Synergism and Implications of Using Carbon Supports with Perovskites for the Oxygen Evolution and Reduction Reaction

Thursday, 1 June 2017: 09:40
Grand Salon A - Section 3 (Hilton New Orleans Riverside)
K. Stevenson (Skolkovo Institute of Technology), C. Alexander (University of Texas at Austin), A. M. Abakumov (Chemistry Department, Lomonosov Moscow State University), and K. P. Johnston (University of Texas at Austin)
Metal-Air batteries and fuel cells are a promising low-cost, high energy density storage solution to make sustainable energy resources and electric vehicles more economically viable than their fossil fuel counterparts. The major limitation that is preventing their widespread adoption are the slow kinetics of the oxygen evolution and reduction reaction which require large overpotentials to obtain reasonable current densities. Additionally, some of the best catalysts for the oxygen evolution and reduction reaction (OER and ORR) are precious metals like IrO2 and Pt respectively which make these devices impractical for large scale use. The most promising path to make a low cost highly bifunctional device is to combine two different catalysts that are separately optimized for the OER and ORR. We show that, by combining N-doped CNTs and LaNiO3, we can achieve a bifunctional window of 0.81 V at 10 and 3 mA/cm2geo for the OER and ORR respectively at 51 μg/cm2 mass loading in 0.1M KOH at room temperature. We also show that carbon corrosion and transition metal dissolution can occur which have led to spurious OER currents to be reported in the literature. Future work should be aimed at increasing the stability of both electrode materials and focusing on developing catalysts that are optimized for either the OER or ORR to combine in a device.