Few-Atomic-Layers Iron for Hydrogen Evolution from Water by Photoelectrocatalysis

Autor: Baowen Zhou, Pengfei Ou, Roksana Tonny Rashid, Srinivas Vanka, Kai Sun, Lin Yao, Haiding Sun, Jun Song, Zetian Mi
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: iScience, Vol 23, Iss 10, Pp 101613- (2020)
Druh dokumentu: article
ISSN: 2589-0042
DOI: 10.1016/j.isci.2020.101613
Popis: 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.
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