Semiconductor interfacial carrier dynamics via photoinduced electric fields

Abstract

Charge separation viewed in reflection When light strikes a semiconductor, excited electrons travel across the interface. Y. Yang et al. applied ultrafast reflection spectroscopy to probe this process in a gallium indium phosphide system used for hydrogen generation from water (see the Perspective by Hansen et al. ). Platinum and titanium dioxide (TiO 2 ) coatings enhanced charge separation of the excited electrons from the positive holes they left behind. TiO 2 , however, was more effective at suppressing the reverse process of unproductive recombination. Science , this issue p. 1061 ; see also p. 1030