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Title: Titanium and Magnesium Co-Alloyed Hematite Thin Films for Photoelectrochemical Water Splitting

Journal Article · · Journal of Applied Physics
DOI:https://doi.org/10.1063/1.3699016· OSTI ID:1045091

Using a combination of density functional theory calculation and materials synthesis and characterization we examine the properties of charge-compensated Ti and Mg co-alloyed hematite thin films for the application of photoelectrochemical (PEC) water splitting. We find that the charge-compensated co-alloying results in the following effects: (1) It enhances the solubility of Mg and Ti, which leads to reduced electron effective mass and therefore increased electron mobility; (2) It tunes the carrier density and therefore allows the optimization of electrical conductivity; and (3) It reduces the density of charged defects and therefore reduces carrier recombination. As a result, the Ti and Mg co-alloyed hematite thin films exhibit improved water oxidation photocurrent magnitudes as compared to pure hematite thin films. Our results suggest that charge-compensated co-alloying is a plausible approach for engineering hematite for the application of PEC water splitting.

Research Organization:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Solar Energy Technologies Office
DOE Contract Number:
AC36-08GO28308
OSTI ID:
1045091
Report Number(s):
NREL/JA-5200-53919; JAPIAU; TRN: US201214%%919
Journal Information:
Journal of Applied Physics, Vol. 111, Issue 7; Related Information: Article No. 073502; ISSN 0021-8979
Country of Publication:
United States
Language:
English

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