Rapid hydrogenation of VO2 thin films via metal-acid contact method using mild electric fields at room temperature

Abstract Five thin films of VO2 were grown on single-crystal sapphire substrates in identical deposition conditions using pulsed excimer laser with an objective to study hydrogenation under different electric fields at room temperature. For hydrogenation, a self-made steup was used with the provision of the negative (film) and positive electrodes in acidic solution. The microstructural, crystallographic and electrical properties were studied in detail. By applying only a trivial voltage of 0.001 mV at 3 cm distance for hydrogenation just for 30 seconds, the resistivity of the film decreased by one order of magnitude at room temperature, indicating incorporation of a good amount of hydrogen in VO2. We find that the hydrogenation is not only sustainable and reversible but a lot more rapid as compared to other techniques.