Texture and Bandgap Tuning of Phase Pure Cu2O Thin Films Grown by a Simple Potentiostatic Electrodeposition Technique

Highly-textured phase pure Cu2O thin films have been grown on fluorine-doped SnO2 substrates by a simple electrodeposition technique with varying deposition voltages (-0.3 to -1.0 V). Surface morphology characterization by scanning electron microscopy revealed that the deposited thin films coherently carpet the underlying substrate and are composed of sharp faceted well-defined grains of 0.5 – 1.0 µm sizes. The optical bandgap of the as-grown samples was calculated in the range of 1.95 – 2.20 eV. The performance of Cu2O films was tested by estimating LED 'ON/OFF' modulated surface photovoltage into a photoelectrochemical cell at a zero bias.