Doping Mo on Tungsten Oxide Thin Film and Photoelectrochemical Measurement

Tungsten oxide (WO3) is semiconductor material which can be used for various applications. Especially, one-dimensional (1-D) nanostructured WO3 shows the high photoelectrochemical (PEC) performance due to high surface area and short transport route of electron–hole pair. The flame vapor deposition (FVD) process is an efficient and economical method for preparation of the 1-D nanos-tructured WO3 thin film. Molybdenum doping is a well-known method to improve the PEC performance of WO3 by reducing band gap and increasing electrical property. In this study, we prepared the 1-D WO3 nanostructures doped with Mo by FVD single step process. We confirmed that Mo was successfully doped on WO3 without changing significantly the original nanostructure, crystal structure and chemical bonding state of WO3 thin film. As a result of PEC measurement, the pho-tocurrent densities of WO3 thin film with Mo doping were higher by about 1.4 to 2 times (for applied voltage above 0.7 V vs. SCE) than those without Mo doping.