Video Experimental Relacionado
Updated: Jul 9, 2025
10:21
Developing Photosensitizer-Cobaloxime Hybrids for Solar-Driven H2 Production in Aqueous Aerobic Conditions
Published on: October 5, 2019
8.4K
Producción de hidrógeno fotocatalítico centrado en ligandos en un complejo de rueda de remo con luz roja
Matthew T Fortunato1, Curtis E Moore1, Claudia Turro1
1Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43214, United States.
Journal of the American Chemical Society
|December 6, 2023
Resumen
Se sintetizaron nuevos complejos de rodio con el ligando bpnp. El complejo 4 demostró la producción fotocatalítica de H2 centrada en el ligando, la primera de este tipo de reacción.
Área de la Ciencia:
- Química de coordinación
- Fotocatálisis
- Ciencias de los materiales
Sus antecedentes:
- Los dímeros de rodio (II,II) son conocidos por sus estructuras electrónicas únicas y su potencial catalítico.
- El diseño de ligandos es crucial para ajustar las propiedades y la reactividad de los complejos metálicos.
- La comprensión de las interacciones metal-ligando es clave para desarrollar fotocatalizadores eficientes.
Objetivo del estudio:
- Sintetizar y caracterizar una nueva serie de complejos de rodio (II,II) con ligandos axiales variables.
- Investigar las propiedades fotofísicas y el comportamiento electroquímico de estos complejos.
- Para explorar su potencial en la producción de hidrógeno fotocatalítico.
Principales métodos:
- Síntesis de complejos cis-[Rh2{DTolF) 2{bpnp) {L) ]2+ (L = pdz, cinn, bncn).
- Análisis electroquímico (voltametría cíclica) para determinar los potenciales de reducción.
- Espectroscopia de absorción UV-Vis para el estudio de las transiciones electrónicas.
- Experimentos fotocatalíticos con irradiación de luz visible en presencia de un reductor de sacrificio y ácido.
Principales resultados:
- Los complejos de rodio sintetizados exhiben distintas bandas de transferencia de carga de metal/ligando a ligando (ML-LCT).
- El complejo 4, con el ligando benzo[c]cinolina (bncn), mostró actividad fotocatalítica para la producción de H2.
- La producción de H2 con un volumen de negocios de 16 se logró utilizando el complejo 4 en condiciones específicas.
- El cierre axial del ligando bpnp impidió la formación de hidruro de Rh-H, localizando la reactividad en el ligando bncn.
Conclusiones:
- El estudio presenta nuevos complejos de rodio (II,II) con propiedades fotofísicas sintonizables.
- El ligando benzo[c]cinolina en el complejo 4 se identifica como el sitio activo para la producción de H2 fotocatalítico.
- Este trabajo demuestra el primer ejemplo de producción de H2 centrada en ligandos en sistemas bimetálicos de rodio.
Videos de Conceptos Relacionados
02:17Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.3K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.3K
02:13Reduction of Alkenes: Catalytic Hydrogenation
12.1K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
12.1K
01:26Photochemical Electrocyclic Reactions: Stereochemistry
1.8K
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
1.8K
01:29The Photochemical Reaction Center
4.1K
Reaction centers are pigment-protein complexes that initiate energy conversion from photons to chemical entities. Therefore, photochemical reaction center is a more appropriate term that describes these complexes. The Nobel laureates Robert Emerson and William Arnold provided the first experimental evidence of photochemical reaction centers by demonstrating the participation of nearly 2,500 chlorophyll molecules for the release of just one molecule of oxygen. Despite thousands of photosynthetic...
4.1K
01:34The Z-Scheme of Electron Transport in Photosynthesis
10.2K
The light reactions of photosynthesis assume a linear flow of electrons from water to NADP+. During this process, light energy drives the splitting of water molecules to produce oxygen. However, oxidation of water molecules is a thermodynamically unfavorable reaction and requires a strong oxidizing agent. This is accomplished by the first product of light reactions: oxidized P680 (or P680+), the most powerful oxidizing agent known in biology. The oxidized P680 that acquires an electron from the...
10.2K
02:24Reduction of Alkynes to cis-Alkenes: Catalytic Hydrogenation
7.7K
Introduction
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
Like alkenes, alkynes can be reduced to alkanes in the presence of transition metal catalysts such as Pt, Pd, or Ni. The reaction involves two sequential syn additions of hydrogen via a cis-alkene intermediate.
7.7K