Effect of processing parameters on anodic nanoporous tungsten oxide film structure and porosity for hydrogen detection

Abstract

Abstract

Review on the Synthesis Methods of Nano-Tungsten Oxide Dihydrate Colloid

“…The electrode where ions are oxidized or neutral substances lose electrons, is called anode whereas ions are reduced or neutral substances gain electrons on the surface of a cathode. The anodization setup is supported by applying the electric field between the two electrodes for a desired period and the electrical current will result in electrochemical reactions on the surface of both the electrodes, which leads to anodic corrosion through an oxidation process causing the materials to be released into the electrolyte medium from corrosive oxidation of the anode [14,26]. Fig.…”

“…Similarly, Yang et al [14] studied the effect of voltage on nanoporous tungsten oxide film structure by anodic oxidation. Sputtered Tungsten layer was used in a typical anodization setup with graphite sheet as counter electrode.…”

“…When the voltage was increased to 30 V, increase in the particle size was noticed as 43 nm pore size was obtained. The porosity of the surface increased and stable structure was obtained at 50 V but raising the potential to 60 V or 80 V destroyed the pore structure and the film consisted of agglomerated oxide particles thus the particle size of the obtained structure also reduced to just above 50 nm [14]. Therefore, both the studies concluded that a gradual increase in particle size was witnessed with increase in applied voltage, but the thickness of oxide layer and nanostructure morphology is compromised at applied potential of above 50 V. It can be deduced from this conclusion that the potential of 50 V is most suitable for the synthesis of tungsten oxide material as regular and stable nanostructures are achieved.…”

“…Considering the significance of Tungsten Oxide Dihydrate due to its extensive properties, researchers have used multiple methods to synthesize this material. Until now, researchers have commonly used sol-gel Synthesis [11], hydrolysis [12], electrodeposition [13] and anodization [14] for the synthesis. Each of these methods have their own impact on the structure of the synthesized material including particle size, conductivity and antibacterial properties hence it is vital to study these methods for the uniformity in synthesis of nano structured tungsten oxide dihydrate for its wider usage in the applications [15][16].…”

Electrodeposition of WO3 Nanoparticles for Sensing Applications

“…An example of a hydrogen gas sensor was built by Yang et al [67] through anodic oxidation of a tungsten layer previously deposited by radio frequency magnetron sputtering on a sapphire substrate (Fig. 6).…”