Characterization of Ag-doped ZnO thin films by spray pyrolysis and its using in enhanced photoelectrochemical performances

Abstract

In this work, Ag:ZnO thin films have been prepared by spraying a mixture of zinc acetate dehydrate and silver nitrate precursors on (ITO)-coated glass substrates at optimized conditions of substrate temperature and a solution concentration. In the current study, we show the effect of Ag doping on the morphological and photoelectrochemical properties of ZnO thin films. The SEM observations exhibit indeed a low change in the size of the surface crystallite after doping. For instance, we have investigated the silver doping effect on the electrochemical behavior taking place at the ZnO/electrolyte interface. The interface has been modeled as an equivalent circuit consisting of a parallel charge transfer resistance RCt and a constant phase element (CPE) in series with a resistance of electrolyte RS. An optimization of the doping percentage has shown that the ZnO photoanode doped with 2% Ag gives the best photoelectrochemical performances.