RT Journal Article
T1 Charge Dynamics as Probed by Small Signal-Modulated Photocurrent and Impedance Spectroscopy of Metal Vanadate Semiconductors and Alloys
A1 Expósito Gálvez, Juan Carlos
A1 Rawat, Abhishek
A1 Rajeshwar, Krishnan
A1 Oskam, Gerko
K1 Photoelectrochemistry
K1 Charge transfer
K1 Carrier recombination
K1 External quantum efficiency
K1 N-type semiconductors
AB This study presents the combined and complementary use of two techniques, namely, intensity modulated photocurrent spectroscopy (IMPS) and photoelectrochemical impedance spectroscopy (PEIS) for the study of partially or wholly replacing copper with an alkaline earth metal (Mg, Ca) in a metavanadate compound matrix (MV2O6). To this end, the three reference compounds (CuV2O6, CaV2O6, MgV2O) and two alloy compositions (Mg0.1Cu0.9V2O6 and Ca0.1Cu0.9V2O6), obtained from a solution combustion technique, were screen-printed on fluorine-doped tin oxide glass (FTO) substrates. Wavelength discrimination for optical excitation of these semiconductor samples was provided by using high-power LED (front-side) illumination with different wavelengths, UV (λ = 370 nm), blue (λ = 455 nm), green (λ = 535 nm), and red (λ = 670 nm). A nonunity photogeneration yield of mobile charge carriers was seen in a trend reminiscent of previous data on binary oxides or even for other types of ternary copper oxides from other laboratories. The dynamic aspects of charge transfer and carrier recombination are discussed using the combined IMPS-PEIS data along with other optical (e.g., diffuse reflectance spectroscopy) and photoelectrochemical data.
PB ACS
YR 2025
FD 2025
LK https://hdl.handle.net/10433/25536
UL https://hdl.handle.net/10433/25536
LA en
NO ACS Appl .Opt. Mater .2025,3, 1684−1695
NO Consejería de Universidad, Investigación e Innovaciónof the Junta de Andalucía (Spain) under grant ProyExcel_00543 (H2SOLDIR)Ministerio de Ciencia e Innovación of Spain, Agencia Estatal de Investigación (AEI) and EU (FEDER) under grants TED2021-129758B-C33 (TransEL) and PID2022-140061OB-I00 (DEEPMATSOLAR).UTA/NU Partnership for Research and Education in Materials (DMR-2425164.
NO Universidad Pablo de Olavide. Departamento de Sistemas Físicos, Químicos y Naturales
DS RIO
RD Apr 27, 2026