Few-Atomic-Layers Iron for Hydrogen Evolution from Water by Photoelectrocatalysis
Baowen Zhou,
Pengfei Ou,
Roksana Tonny Rashid,
Srinivas Vanka,
Kai Sun,
Lin Yao,
Haiding Sun,
Jun Song,
Zetian Mi
Affiliations
Baowen Zhou
Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, MI 48109, USA; Department of Electrical and Computer Engineering, McGill University, 3480 University Street, Montreal, QC H3A 0E9, Canada
Pengfei Ou
Department of Mining and Materials Engineering, McGill University, 3610 University Street, Montreal, QC H3A 0C5, Canada
Roksana Tonny Rashid
Department of Electrical and Computer Engineering, McGill University, 3480 University Street, Montreal, QC H3A 0E9, Canada
Srinivas Vanka
Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, MI 48109, USA
Kai Sun
Department of Materials Science and Engineering, University of Michigan, 2300 Hayward Street, Ann Arbor, MI 48109, USA
Lin Yao
Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, 19 Zhongguancundonglu, Beijing 100190, P. R. China
Haiding Sun
School of Microelectronics, University of Science and Technology of China, 244 Huangshan Road, Hefei, Anhui 230026, P. R. China
Jun Song
Department of Mining and Materials Engineering, McGill University, 3610 University Street, Montreal, QC H3A 0C5, Canada; Corresponding author
Zetian Mi
Department of Electrical Engineering and Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, MI 48109, USA; Department of Electrical and Computer Engineering, McGill University, 3480 University Street, Montreal, QC H3A 0E9, Canada; Corresponding author
Summary: The carbon-free production of hydrogen from water splitting holds grand promise for the critical energy and environmental challenges. Herein, few-atomic-layers iron (FeFAL) anchored on GaN nanowire arrays (NWs) is demonstrated as a highly active hydrogen evolution reaction catalyst, attributing to the spatial confinement and the nitrogen-terminated surface of GaN NWs. Based on density functional theory calculations, the hydrogen adsorption on FeFAL:GaN NWs is found to exhibit a significantly low free energy of −0.13 eV, indicative of high activity. Meanwhile, its outstanding optoelectronic properties are realized by the strong electronic coupling between atomic iron layers and GaN(10ī0) together with the nearly defect-free GaN NWs. As a result, FeFAL:GaN NWs/n+-p Si exhibits a prominent current density of ∼ −30 mA cm−2 at an overpotential of ∼0.2 V versus reversible hydrogen electrode with a decent onset potential of +0.35 V and 98% Faradaic efficiency in 0.5 mol/L KHCO3 aqueous solution under standard one-sun illumination.
