In this section
@article{Liu:2026:10.1039/d6se00618c,
author = {Liu, A and Kafizas, A and Ma, Y},
doi = {10.1039/d6se00618c},
journal = {Sustainable Energy and Fuels},
title = {Time-resolved spectroscopic insights into the surface energetics of SrTiO3 for water oxidation},
url = {http://dx.doi.org/10.1039/d6se00618c},
year = {2026}
}
TY - JOUR
AB - Time-resolved spectroscopies are employed to study the bias-dependent reaction kinetics of hole carriers in SrTiO<inf>3</inf> photoanodes for the water oxidation reaction. Their behavior is investigated with transient absorption and steady-state photoinduced absorption spectroscopies, focusing on the µs–s timescales that span the catalysis of water splitting. Rate law analyses are used to interpret the behavior of photogenerated holes for the water oxidation reaction, revealing second order behavior with respect to hole carriers for the rate limiting step with turnover frequencies on the order of ∼0.01–0.1 s<sup>−1</sup> observed. Unique to SrTiO<inf>3</inf>, band edge unpinning is observed, and associated with Ti<sup>3+</sup> electron traps located 0.95 eV below the conduction band, causing a shift in the conduction and valence band edges with applied potential, resulting in water oxidation kinetics that varied with applied potential too. In comparison, the kinetics of TiO<inf>2</inf> are found to be insensitive to applied potential, consistent with the Schottky junction model, where the conduction and valence band edges at the semiconductor–electrolyte interface are pinned with TOFs for hole carriers on the order of ∼5 s<sup>−1</sup>. Reconstruction of the photocurrent behavior, based on these two energetic models for SrTiO<inf>3</inf> and TiO<inf>2</inf>, highlighted the distinct differences in charge carrier dynamics and energetics in these systems despite their similar optoelectronic properties. Ultimately, we rationalize the engineering principles – that can be extended to other metal oxides – to inhibit band edge unpinning and achieve enhanced water splitting efficiency.
AU - Liu,A
AU - Kafizas,A
AU - Ma,Y
DO - 10.1039/d6se00618c
PY - 2026///
TI - Time-resolved spectroscopic insights into the surface energetics of SrTiO3 for water oxidation
T2 - Sustainable Energy and Fuels
UR - http://dx.doi.org/10.1039/d6se00618c
ER -
Dr. Andreas Kafizas
Leader - Solar Coatings Group
e-mail: a.kafizas@imperial.ac.uk
tel: +44(0)20 7594 6752
twitter: @CoatingsSolar