Cathodic electrodeposition of ZnO and CuSCN thin films in the presence of glutathione

Abstract

The effect of a tripeptide molecule glutathione (γ-L-glutamyl-L-cysteniylglycine, QCG) is studied as a structure-directing agents (SDA) for cathodic electrodeposition of ZnO and CuSCN from aqueous solutions, which are known to be wide bandgap semiconductors of n and p types, respectively. From experiences, hard Lewis basic –COOH group act as an anchor to the hard Lewis acidic Zn(II) sites of ZnO, whereas soft Lewis basic groups such as –SH and –NH2 are expected to interact with soft Lewis acidic Cu(I) sites of CuSCN. QCG have all these anchoring groups within its structure and was found to affect the growth of both ZnO and CuSCN, leading to alteration of crystallographic orientations and evolution of unique nanostructures.