Home > Articles > Published articles > Control of the polarization of ferroelectric capacitors by the concurrent action of light and adsorbates |
Date: | 2018 |
Abstract: | Ferroelectric perovskites hold promise of enhanced photovoltaic efficiency and photocatalytic activity. Consequently, the photoresponse of oxide ferroelectric thin films is an active field of research. In electrode/ferroelectric/electrode devices, internal charge in the ferroelectric, free charge in the electrodes, and buried adsorbates at interfaces combine to screen the ferroelectric polarization and to stabilize the polar state. Under illumination, photoinduced carriers and photodissociated adsorbates may disrupt the screening equilibrium, modifying the switchable polarization and altering its expected benefits. Here, we explore the photoresponse of BaTiO thin films in a capacitor geometry, focusing on the effects of visible illumination on the remanent polarization. By combining ferroelectric and X-ray photoelectron spectroscopy, we discover that photoreaction of charge-screening HO-derived adsorbates at the buried metal-ferroelectric Pt/BaTiO interface plays an unexpected pivotal role, enabling a substantial modulation (up to 75%) of the switchable remanent polarization by light. These findings illustrate that the synergy between photochemistry and photovoltaic activity at the surface of a ferroelectric material can be exploited to tune photoferroelectric activity. |
Grants: | Ministerio de Economía y Competitividad MAT2017-85232-R Ministerio de Economía y Competitividad SEV-2015-0496 Ministerio de Economía y Competitividad MAT2015-73839-JIN Ministerio de Economía y Competitividad MAT2014-56063-C2-1-R Ministerio de Economía y Competitividad IJCI-2014-19102 Ministerio de Economía y Competitividad SEV-2013-0295 Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-734 |
Note: | Altres ajuts: the ICN2 is funded by the CERCA programme/ Generalitat de Catalunya. |
Rights: | Tots els drets reservats. |
Language: | Anglès |
Document: | Article ; recerca ; Versió acceptada per publicar |
Subject: | Ferroelectric ; Photovoltaic ; Water ; Adsorbates ; Photocatalysis ; Barium titanate ; Screening ; Depolarization field |
Published in: | ACS applied materials & interfaces, Vol. 10, issue 28 (July 2018) , p. 23968-23975, ISSN 1944-8252 |
Postprint 25 p, 1.2 MB |