Photo-induced electron transfer between hypocrellins and nano-sized semiconductor CdS : -EPR study on the kinetics of photosensitized reduction in HA-CdS and HB-CdS systems

Science in China. Series C, Life Sciences
Z ZhouZ Zhang

Abstract

Both HA-CdS and HB-CdS (Hys-CdS, Hys represents HA, HB) complex systems were established according to the dynamics of heterogeneous electron-transfer process[Formula: see text]. In these systems, the electron transferring from(1)Hys* to conduction band of CdS is feasible. Determined from the fluorescence quenching, the apparent association constants (K(app)) between Hypocrellin A (HA), Hypocrellin B. (HB) and CdS sol. were about 940 (mol/L)(-1), 934 (mol/L)(-1), respectively. Fluorescence lifetime measurements gave the rate constant for the electron transfer process from(1)HA*,(1)HB* into conduction band of CdS semiconductor as 5.16 x 10(9) s(-1), 5.10 x 10(9) s(-1), respectively. TEMPO (2,2,6,6-tetramethy-1-piperdinyloxy), a stable nitroxide radical, was used in the kinetic study of the reduction reaction taking place on the surface of a CdS colloidal semiconductor, kinetics equation of the reaction was determined with the electron paramagnetic resonance (EPR) method, and the reaction order of TEMPO is zero. When Hys were added, the rate of EPR increased greatly. By comparing rate constants, the Hys-CdS systems were revealed to be about 350 times more efficient than CdS sol. alone in the photoreduction of TEMPO under visible l...Continue Reading

References

Jul 15, 1992·Journal of Photochemistry and Photobiology. B, Biology·W Nenghui, Z Zhiyi

❮ Previous
Next ❯

Citations


❮ Previous
Next ❯

Related Concepts

Related Feeds

Cardiac Conduction System

The cardiac conduction system is a specialized tract of myocardial cells responsible for maintaining normal cardiac rhythm. Discover the latest research on the cardiac conduction system here.

Related Papers

Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
A Kathiravan, R Renganathan
Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
A KathiravanS Sekar
Journal of Colloid and Interface Science
A Kathiravan, R Renganathan
© 2022 Meta ULC. All rights reserved