title: Blending Cr2O3 into a NiO-Ni electrocatalyst for sustained water splitting.
abstract: The rising H2 economy demands active and durable electrocatalysts based on low-cost, earth-abundant materials for water electrolysis/photolysis. Here we report nanoscale Ni metal cores over-coated by a Cr2 O3 -blended NiO layer synthesized on metallic foam substrates. The Ni@NiO/Cr2 O3 triphase material exhibits superior activity and stability similar to Pt for the hydrogen-evolution reaction in basic solutions. The chemically stable Cr2 O3 is crucial for preventing oxidation of the Ni core, maintaining abundant NiO/Ni interfaces as catalytically active sites in the heterostructure and thus imparting high stability to the hydrogen-evolution catalyst. The highly active and stable electrocatalyst enables an alkaline electrolyzer operating at 20 mA cm(-2) at a voltage lower than 1.5 V, lasting longer than 3 weeks without decay. The non-precious metal catalysts afford a high efficiency of about 15 % for light-driven water splitting using GaAs solar cells.
authors: Department of Chemistry, Stanford University, Stanford, CA 94305 (USA).
authors: Ming
authors: M
authors: Gong
authors: Materials Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (USA).
authors: Wu
authors: W
authors: Zhou
authors: Department of Chemistry, Stanford University, Stanford, CA 94305 (USA).
authors: Michael James
authors: MJ
authors: Kenney
authors: Alta Devices, Sunnyvale, CA 94805 (USA).
authors: Rich
authors: R
authors: Kapusta
authors: Alta Devices, Sunnyvale, CA 94805 (USA).
authors: Sam
authors: S
authors: Cowley
authors: Department of Chemistry, Stanford University, Stanford, CA 94305 (USA).
authors: Yingpeng
authors: Y
authors: Wu
authors: Department of Chemistry, Stanford University, Stanford, CA 94305 (USA).|School of Physics and Electronics, Hunan University, Changsha, 410082 (China).
authors: Bingan
authors: B
authors: Lu
authors: Department of Chemistry, Stanford University, Stanford, CA 94305 (USA).|Green Energy and Environment Research Laboratories, Industrial Technology Research Insititute, Hsinchu, 31040 (Taiwan, ROC).
authors: Meng-Chang
authors: MC
authors: Lin
authors: Department of Chemistry, Stanford University, Stanford, CA 94305 (USA).|Department of Chemistry, National Taiwan Normal University, Taipei, 11677 (Taiwan, ROC).
authors: Di-Yan
authors: DY
authors: Wang
authors: Department of Chemistry, Stanford University, Stanford, CA 94305 (USA).
authors: Jiang
authors: J
authors: Yang
authors: Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei, 106 (Taiwan, ROC).
authors: Bing-Joe
authors: BJ
authors: Hwang
authors: Department of Chemistry, Stanford University, Stanford, CA 94305 (USA). hdai@stanford.edu.
authors: Hongjie
authors: H
authors: Dai
keywords: chromium oxide; electrocatalysts; hydrogen-evolution reaction; sustainable chemistry; water splitting