Direct Observation of the Chemical Transformations in BiVO4 Photoanodes upon Prolonged Light-Aging Treatments

Exposing BiVO photoanodes to light-aging treatments is known to produce a significant photocurrent enhancement. Until now, the interpretation given to this phenomenon is associated to the formation of oxygen vacancies and little is reported about chemical changes in the material. Herein, the chemica...

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Detalles Bibliográficos
Autores: Arcas, Ramón, Cardenas-Morcoso, Drialys, Spadaro, Maria Chiara, García-Tecedor, Miguel, Mesa, Camilo A., Arbiol, Jordi, Fabregat-Santiago, Francisco, Giménez, Sixto, Mas-Marzá, Elena
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2022
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/280553
Acceso en línea:http://hdl.handle.net/10261/280553
Access Level:acceso abierto
Palabra clave:Bi segregation
BiVO4
Light-aging treatments
Oxygen vacancies
Descripción
Sumario:Exposing BiVO photoanodes to light-aging treatments is known to produce a significant photocurrent enhancement. Until now, the interpretation given to this phenomenon is associated to the formation of oxygen vacancies and little is reported about chemical changes in the material. Herein, the chemical segregation of Bi species toward the surface upon light-aging treatment is demonstrated, which takes place with the concomitant formation of intra-bandgap states associated to the oxygen vacancies. It is further demonstrated that these intra-bandgap states are photoactive and generate photocurrent under infrared excitation. These results highlight the importance of understanding light-induced effects while employing multinary metal oxide photoelectrodes.