Determination of the flatband potential of semiconductor particles in suspension by photovoltage measurement

Abstract The flatband potentials, Efb, of CdS and CdS Ag 2 S (1.5wt%) particles have been determined from photovoltage measurements in the presence of electron acceptor methyl viologen (MV2+). Measurements have been taken whilst irradiating the semiconductor suspensions with visible light. This is one of the simplest and newly developed techniques for the determination of the Efb of semiconductors. The Efb for CdS and CdS Ag 2 S (1.5wt%) are found to be −0.724 V and −0.761 V respectively vs SCE at pH 14.

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