Showing papers by "Prashant V. Kamat published in 1988"

Photoelectrochemistry in particulate systems. 7. Electron-transfer reactions of indium sulfide semiconductor colloids

Abstract: Small semiconductor colloids of In/sub 2/S/sub 3/ have been prepared in aqueous and nonaqueous media and their absorption properties characterized. A transient photobleaching and formation of S/sup .-/ and S/sub 2/H/sub 2//sup .-/ radicals have been observed upon laser pulse (355 nm) excitation of these colloids. With the aid of transient absorption spectra, the anodic corrosion process in these semiconductor colloids has been elucidated by using laser flash photolysis and pulse radiolysis techniques. With the use of a zwitterionic viologen compound, the interfacial charge-transfer process at the semiconductor surface has been studied. The quantum yield for the reduction of zwitterionic viologen was 0.07, which is similar to the value obtained with other metal chalcogenide semiconductor colloids. The microenvironment of the stabilizer (Nafion) influenced the charge-transfer process between the semiconductor and the redox decay.