Optical and structural characterization of tungsten oxide electrodeposited on nanostructured porous silicon: Effect of annealing atmosphere and temperature

•WO3/PS composite results in an increase in effective surface area of WO3.•Temperature dependence of PL shows annihilation/enhancement of signal in air/N2.•Rectifying behavior of WO3/PS decreases by ∼7 times after annealing under N2.•Potential applications: increase in sensing/catalytic performance of WO3 and LEDs. Optical and structural properties of tungsten oxide (WO3), electrodeposited on luminescent nanostructured porous silicon (PS) have been investigated as a function of annealing atmosphere and temperature. Physical and optical properties of WO3/PS hybrid structures were analyzed using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and photoluminescence (PL) spectroscopy. Our experimental results reveal that evolution of PL peak, corresponding to band edge emission of WO3, increases with annealing temperature under nitrogen atmosphere in contrast with air atmosphere. Rectifying behavior of WO3/PS structures exhibits a decrease by a factor of approximately 7 in the annealed sample as compared to as deposited samples under nitrogen conditions. Such composites have potential applications in diodes technology as well as in improving sensing/catalytic performance of WO3.