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Vinculando la diferencia de potencial de superficie fotoinducida a la transferencia de carga interfacial en la
Ruotian Chen1, Deyun Zhang1,2, Ziyuan Wang1,3
1State Key Laboratory of Catalysis, Dalian National Laboratory for Clean Energy, iChEM, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Zhongshan Road 457, Dalian, Liaoning 116023, China.
Journal of the American Chemical Society
|February 16, 2023
Resumen
Las reacciones superficiales mejoran la fotovoltaje en la fotoelectrocatálisis al permitir una nueva vía de transferencia de carga. Este estudio revela una correlación lineal entre los cambios de potencial superficial y las tasas de oxidación del agua, ofreciendo una regla general para la transferencia de carga interfacial.
Área de la Ciencia:
- Ciencias de los materiales
- La electroquímica
- Fotocatálisis
Sus antecedentes:
- La transferencia de carga en las interfaces semiconductor/solución es crucial para la división fotoelectrocatalítica del agua.
- La comprensión de la transferencia de carga interfacial en la fotoelectrocatálisis es compleja debido a la luz, el sesgo y los efectos catalíticos.
- Las teorías existentes como Butler-Volmer están limitadas para los sistemas fotoelectrocatalíticos.
Objetivo del estudio:
- Para desacoplar los procesos de transferencia de carga y reacción de superficie en la fotoelectrocatálisis.
- Investigar el papel de las reacciones superficiales en el aumento de la fotovoltaica.
- Establecer una regla general para la transferencia de carga interfacial en la fotoelectrocatálisis.
Principales métodos:
- Las mediciones del potencial de superficie operando.
- Se utilizó un fotoánodo de titanato de estroncio (SrTiO3).
- Analizó la correlación entre los cambios de potencial de superficie y las tasas de transferencia de carga interfacial.
Principales resultados:
- Identificó un régimen de transferencia de carga fotoinducida relacionado con la reacción que mejora la fotovoltaica.
- Se demostró una correlación lineal entre la transferencia de carga relacionada con la reacción y las tasas de oxidación del agua.
- Este comportamiento lineal es independiente del sesgo aplicado y la intensidad de la luz.
Conclusiones:
- Las reacciones superficiales mejoran significativamente la fotovoltaica a través de un mecanismo de transferencia de carga distinto.
- Se ha descubierto una regla lineal general para la transferencia de carga interfacial en la fotoelectrocatálisis.
- Esta regla proporciona un marco fenomenológico para comprender la transferencia de carga interfacial en la división del agua.
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