Combined Theoretical and Experimental Investigations of Atomic Doping To Enhance Photon Absorption and Carrier Transport of LaFeO3 Photocathodes
Year: 2019
Type: article
Abstract: Perovskite-type lanthanum iron oxide, LaFeO 3, is a p-type semiconductor that can achieve overall water splitting using visible light while maintaining photostability. These features make LaFeO 3 a promising photocathode candidate for various photoelectrochemical cells. Currently, the photoelectrochemical performance of a LaFeO 3 photocathode is mainly limited by considerable bulk electron–hole recombination. This study reports a combined theoretical and experimental investigation on the atomic doping of LaFeO 3, in particular, substitutional doping of La 3+ with K +, to increase its charge-transport properties and decrease electron–hole recombination. The computational results show that K-doping enhances not only the charge-transport properties but also photon absorption below the bandgap energy of the pristine LaFeO 3 . The effect of K-doping was systematically investigated by comparing the electronic and atomic structures, majority carrier density, hole-polaron formation, and optical properties of pristine and K-doped LaFeO 3 . The computational results were then verified by experimentally characterizing the crystal structures, compositions, optical properties, and photoelectrochemical properties of LaFeO 3 and K-doped LaFeO 3 electrodes. For this purpose, pristine LaFeO 3 and K-doped LaFeO 3 were prepared as high-surface-area, high-purity photoelectrodes having the same morphology to accurately and unambiguously evaluate the effect of K-doping. The combined computational and experimental investigations presented in this study provide useful insights into the effect of composition tuning of LaFeO 3 and other p-type oxides with a perovskite structure.
Source: Chemistry of Materials
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: green
Awards: G1285306620, G1847291448, G241279073, G3226045097, G3262563802, G357145406, G4258199888, G5102516135, G5696392313, G5765906131, First-Principles Design of Charged Defects for Two-dimensional Quantum Technologies, G6965541988, Understanding and Enhancing Electronic Coupling Between Metal Halide Perovskite Quantum Dots Through Surface Molecular Engineering, G7463374569, ELECTROCHEMICAL SYNTHESIS OF POLYCRYSTALLINE SEMICONDUCTOR ELECTRODES WITH CONTROLLED COMPOSITIONS AND MORPHOLOGIES FOR USE IN SOLAR FUEL PRODUCTION, G872144517, G951619839
OpenAlex ID: W2957364075