Interplay of band energetics and photo/electro/chemical activity of SnO2 thin films

Abstract

The ALD-SnO2 thin films are prepared at FTO and Au(111) substrates. Their investigation is referenced, if relevant, to a model system of SnO2 cassiterite (001) single crystal. Open questions about the photoelectrochemical activity and band energetics after calcination and UV-excitation are addressed. We analyze the data from AFM, Raman, Kelvin probe, photoelectrochemistry of water oxidation and electrochemical impedance spectroscopy (flatband potentials determined from Mott–Schottky plots) in aqueous and acetonitrile media. Calcination of ALD-SnO2 causes strong enhancement of work functions, surface coarsening, and decrease of band-gap. Graphical abstract: (Figure presented.).