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El control de relajación de la atmósfera iónica de la dinámica de transferencia de electrones en una fusión
Dongil Lee1, Amanda S Harper, Joseph M DeSimone
1Kenan Laboratories of Chemistry and NSF Science & Technology Center for Environmentally Responsible Solvents and Processes, University of North Carolina, Chapel Hill, NC 27599, USA.
Journal of the American Chemical Society
|January 23, 2003
Resumen
La sorción de dióxido de carbono mejora el transporte de carga en las fusiones de poliéteres redox. Este estudio revela que la presión de CO2 aumenta la difusión y las tasas de autointercambio de electrones, controladas por la relajación del contraion y la dinámica del disolvente poliéter.
Área de la Ciencia:
- La electroquímica es electroquímica.
- Ciencia de los materiales Ciencia de los materiales.
- Química Física es la química física.
Sus antecedentes:
- Los materiales de sales fundidas son prometedores para aplicaciones electroquímicas.
- Comprender los mecanismos de transporte de carga es crucial para optimizar el rendimiento del material.
- Las fusiones híbridas de poliéter redox ofrecen propiedades únicas para el almacenamiento y la conversión de energía.
Objetivo del estudio:
- Para investigar el efecto de la absorción de dióxido de carbono (CO2) en el transporte de carga en una fusión híbrida de poliéter redox.
- Para determinar cómo la presión de CO2 influye en los coeficientes de difusión y las tasas de autointercambio de electrones.
- Para aclarar la relación entre los parámetros de transporte de carga y las propiedades físicas del material.
Principales métodos:
- Las mediciones electroquímicas se llevaron a cabo en un poliéter redox híbrido fundido, [Co(fenantrolina) ((3)) ](MePEG-SO ((3)) ((2)).
- La presión de CO2 fue variada de 0 a 800 psi (54 atm) a 23 grados C.
- Se midieron los coeficientes de difusión física (D ((PHYS), D ((COUNTERION)) y las constantes de la tasa de autocambio de electrones (k ((EX)).
Principales resultados:
- La sorción de CO2 aceleró significativamente el transporte de carga en la sal fundida.
- El aumento de la presión de CO2 condujo a un mayor D ((PHYS), k ((EX) y D ((COUNTERION)).
- Las tasas de autointercambio de electrones se correlacionan linealmente con los coeficientes de difusión, en particular D ((COUNTERION).
Conclusiones:
- Las constantes de la velocidad de autointercambio de electrones están controladas por la relajación de la atmósfera de contrarios alrededor de los complejos de cobalto.
- Las fluctuaciones del disolvente poliéter, influenciadas por la sorción de CO2, rigen la relajación de la contración.
- Este trabajo demuestra un nuevo mecanismo de dinámica de disolventes que controla la transferencia de electrones en fundidos redox semisólidos.
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