Work

Efficient Suppression of Electron–Hole Recombination in Oxygen-Deficient Hydrogen-Treated TiO2 Nanowires for Photoelectrochemical Water Splitting

Year: 2013

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide There is an increasing level of interest in the use of black TiO 2 prepared by thermal hydrogen treatments (H:TiO 2 ) due to the potential to enhance both the photocatalytic and the light-harvesting properties of TiO 2 . Here, we examine oxygen-deficient H:TiO 2 nanotube arrays that have previously achieved very high solar-to-hydrogen (STH) efficiencies due to incident photon-to-current efficiency (IPCE) values of >90% for photoelectrochemical water splitting at only 0.4 V vs RHE under UV illumination. Our transient absorption (TA) mechanistic study provides strong evidence that the improved electrical properties of oxygen-deficient TiO 2 enables remarkably efficient spatial separation of electron–hole pairs on the submicrosecond time scale at moderate applied bias, and this coupled to effective suppression of microsecond to seconds charge carrier recombination is the primary factor behind the dramatically improved photoelectrochemical activity.

Source: The Journal of Physical Chemistry C

DOI: 10.1021/jp4099914

Authors: Federico M. Pesci, Gongming Wang, David R. Klug, Yat Li, Alexander J. Cowan

Institutions: Imperial College London, University of California, Santa Cruz, University of Liverpool

Language: English

Topic: TiO2 Photocatalysis and Solar Cells

Subfield: Renewable Energy, Sustainability and the Environment

Field: Energy

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $4,500