The influence of PdO content on circular photocurrent in resistive Ag/Pd films

Resumo

We have studied the influence of PdO content in resistive Ag/Pd films (consisting of this oxide and Ag–Pd solid solution) on photocurrent dependent on the sign of circular polarization of the exciting radiation. The photocurrent was excited by nanosecond pulsed laser radiation with a 532 nm wavelength and measured in the direction perpendicular to the plane of laser beam incidence onto the film. The content of PdO in the film was varied by electrolytic reduction of Pd from PdO in sulfuric acid solution. Raman spectroscopy and X-ray diffraction measurements showed that reduced PdO content in the film leads to nonlinear decrease in the magnitude of photocurrent. It is established that photocurrent is also observed when PdO is fully absent on the film surface. The obtained results suggest that the nature of photocurrent in Ag/Pd films is related to the structure of Ag–Pd solid solution.