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Regulación de la coordinación de un solo átomo de Rh para el derrame inverso de hidrógeno mejorado y la
Qian Zheng1, Hengyue Xu2, Yancai Yao1
1State Key Laboratory of Green Papermaking and Resource Recycling, School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.
Journal of the American Chemical Society
|November 12, 2025
Resumen
La optimización de la coordinación de un solo átomo Rh mejora el derrame inverso de hidrógeno para una hidrogenación electroquímica eficiente. Un electrodo Rh de cuatro oxígenos coordinados (Rh1O4) muestra un rendimiento superior en la electrólisis del agua, crucial para la catálisis sostenible.
Área de la Ciencia:
- Ciencias de los materiales
- La electroquímica
- Catálisis
Sus antecedentes:
- El derrame inverso de hidrógeno (RHS) es clave para la hidrogenación electroquímica, que se basa en la transferencia de hidrógeno atómico desde las superficies del catalizador.
- La eficiencia del RHS es muy sensible al entorno de coordinación y a la estructura electrónica de los sitios catalíticos monoatómicos.
Objetivo del estudio:
- Investigar el impacto de la coordinación de un solo átomo de Rh en las superficies de óxido de titanio para RHS durante la electrólisis del agua.
- Para correlacionar el número de coordinación de átomos Rh individuales con su estructura electrónica y eficiencia RHS.
- Establecer un marco para el diseño de electrocatalizadores avanzados de un solo átomo para reacciones de hidrogenación.
Principales métodos:
- Electrolisis electroquímica del agua mediante electrodos de espuma de titanio funcionalizados con átomos Rh individuales.
- Caracterización de los entornos de coordinación de un solo átomo Rh (Rh1O4, Rh1O5, Rh1O3) y sus estructuras electrónicas.
- Medición de la adsorción de hidrógeno en las barreras de energía libre de Gibbs (ΔGH*) y RHS.
Principales resultados:
- Un electrodo de un solo átomo Rh coordinado con cuatro átomos de oxígeno (Rh1O4) demostró una capacidad RHS superior en comparación con Rh1O5 y Rh1O3.
- Rh1O4 logró un ΔGH* optimizado de +0,08 eV y una barrera de energía RHS reducida de +0,55 eV.
- El Rh1O4 exhibió una constante de tasa de degradación del 4-clorfenol de 4,65 h-1, superando significativamente el Rh1O5 (1,18 h-1) y el Rh1O3 (0,16 h-1).
Conclusiones:
- La ingeniería de coordinación de un solo átomo es crítica para ajustar la dinámica de transferencia de hidrógeno atómico en RHS.
- El número de coordinación Rh-O influye directamente en el centro de la banda d de Rh, optimizando la adsorción de H* y la eficiencia de la RHS.
- La configuración Rh1O4 proporciona un modelo estratégico para el desarrollo de electrocatalizadores monoatómicos de alto rendimiento para la hidrogenación sostenible.
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