Wei Huang1, Catalin Harnagea1, Xin Tong1,2, Daniele Benetti1, Shuhui Sun1, Mohamed Chaker1, Federico Rosei1,3, Riad Nechache4. 1. Centre Énergie, Matériaux et Télécommunications , Institut National de la Recherche Scientifique , 1650, Boulevard Lionel-Boulet , Varennes , Québec J3X 1S2 , Canada. 2. School of Chemistry and Materials Science , Guizhou Normal University , Guiyang 550001 , People's Republic of China. 3. Institute of Fundamental and Frontier Science , University of Electronic Science and Technology of China , Chengdu 610054 , People's Republic of China. 4. École de Technologie Supérieure , 1100 Rue Notre-Dame Ouest , Montréal , Québec H3C 1K3 , Canada.
Abstract
The photoelectric properties of multiferroic double-perovskite Bi2FeCrO6 (BFCO), such as above-band gap photovoltages, switchable photocurrents, and bulk photovoltaic effects, have recently been explored for potential applications in solar technology. Here, we report the fabrication of photoelectrodes based on n-type ferroelectric (FE) semiconductor BFCO heterojunctions coated with p-type transparent conducting oxides (TCOs) by pulsed laser deposition and their application for photoelectrochemical (PEC) water oxidation. The photocatalytic properties of the bare BFCO photoanodes can be improved by controlling the FE polarization state. However, the charge recombination as well as the limited charge transfer kinetics in the photoanode/electrolyte cause major energy loss and thus hinder the PEC performance. We show that this problem may be addressed by the deposition of an ultrathin p-type NiO layer on the photoanode to enhance the charge transport kinetics and reduce charge recombination at surface-trapped states for increased surface band bending. A fourfold enhancement of photocurrent density, up to 0.4 mA cm-2 (at +1.23 V vs RHE), a best performance of stability over 4 h, and a high incident photon-to-current efficiency (∼3.7%) were achieved under 1 sun illumination in such p-NiO/n-BFCO heterojunction photoanodes. These studies reveal the optimization of PEC performance by polarization switching of BFCO and the successful achievement of p-TCOs/n-FE heterojunction photoanodes that are able to sustain water oxidation that is stable for many hours.
The photoelectric properties of multiferroic n class="Chemical">double-perovskite Bi2FeCrO6 (pan> class="Chemical">BFCO), such as above-band gap photovoltages, switchable photocurrents, and bulk photovoltaic effects, have recently been explored for potential applications in solar technology. Here, we report the fabrication of photoelectrodes based on n-type ferroelectric (FE) semiconductor BFCO heterojunctions coated with p-type transparent conducting oxides (TCOs) by pulsed laser deposition and their application for photoelectrochemical (PEC) water oxidation. The photocatalytic properties of the bare BFCOphotoanodes can be improved by controlling the FE polarization state. However, the charge recombination as well as the limited charge transfer kinetics in the photoanode/electrolyte cause major energy loss and thus hinder the PEC performance. We show that this problem may be addressed by the deposition of an ultrathin p-type NiO layer on the photoanode to enhance the charge transport kinetics and reduce charge recombination at surface-trapped states for increased surface band bending. A fourfold enhancement of photocurrent density, up to 0.4 mA cm-2 (at +1.23 V vs RHE), a best performance of stability over 4 h, and a high incident photon-to-current efficiency (∼3.7%) were achieved under 1 sun illumination in such p-NiO/n-BFCO heterojunction photoanodes. These studies reveal the optimization of PEC performance by polarization switching of BFCO and the successful achievement of p-TCOs/n-FE heterojunction photoanodes that are able to sustain water oxidation that is stable for many hours.
Authors: Adriana Augurio; Alberto Alvarez-Fernandez; Vishal Panchal; Bede Pittenger; Peter De Wolf; Stefan Guldin; Joe Briscoe Journal: ACS Appl Mater Interfaces Date: 2022-03-10 Impact factor: 9.229