Electrical characterization of H2S adsorption on hexagonal WO3 nanowire at room temperature

Abstract

We have characterized the electrical transport properties of Au/WO 3 nanowire/Au devices in ambient air and gaseous H 2 S to investigate the adsorption kinetics of H 2 S molecules on the surface of WO 3 nanowire at room temperature. The WO 3 nanowire devices exhibit increasing linear conductance and electrical hysteresis in H 2 S. Furthermore, the contact type between Au electrode and WO 3 nanowire can be converted from original ohmic/Schottky to Schottky/ohmic after being exposed to H 2 S. These results suggest that adsorbed H 2 S molecules are oxidized by holes to form hydrogen ions and S atoms, which will result in formation of hydrogen tungsten bronze and desorption of previously chemically adsorbed H 2 O molecules. Adsorbed H 2 S molecules can also oxidize previously adsorbed and ionized oxygen, which will release the electrons from the ionized oxygen and then weaken upward band bending at the surface of WO 3 nanowire. V C 2014 AIP Publishing LLC. [http://dx.

Large-scale synthesis and quantitative characterization of size-controllable potassium tungsten bronze nanowires

“…Therefore, the unnatural increase in the crystal lattice microstrain might be attributed to the aggregation of potassium ions induced by heat treatment in the 1D hexagonal channels. In the as-synthesized K 0.26 WO 3 nanowires (x = 0.26 < 0.33), the evenly distributed K + ion vacancies prefer to order or aggregate to form superlattice structures during annealing just like in its 2D and 3D systems [20,21,26]. After all, the as-synthesized K 0.26 WO 3 nanowires have also been turned into particles after being oxidized in oxygen atmosphere, in which WO 3 and K 2 OW 7 O 21 phases can be detected by XRD (datum reported elsewhere).…”

“…Hexagonal M x WO 3 nanowires grow always along the c direction under normal conditions [11][12][13][14][15][16], and then the M + ions in the 1D tunnels can drift or diffuse easily along the axial direction under external excitation such as electrical field [17]. Therefore, the electrical properties such as the resistance as well as the optical properties such as the color can be well modulated simultaneously by modulating the distribution of the M + ions along the nanowire [18][19][20]. The resistive switching performance of the Au/h-WO 3 nanowire/Au device can be enhanced remarkably when the water-oxidized hydrogen ions are implanted into WO 3 lattice [21][22][23][24][25].…”

Research Progress of Gas Sensing Performance of 2D Hexagonal WO3

“… The microstructure of h-WO 3 nanoparticle, nanowire, film, and nanosphere (A) 0D h-WO 3 nanoparticle ( Szilágyi et al, 2010 ). (B) 1D h-WO 3 nanowire ( Liu et al, 2014 ). (C) 2D h-WO 3 film ( Meng et al, 2015 ).…”

Phase-Control-Enabled Enhancement in Hydrophilicity and Mechanical Toughness in Nanocrystalline Tungsten Oxide Films for Energy-Related Applications

“…12−15 In fact, the design and development of novel architectures of stoichiometric or nonstoichiometric WO 3 and their hydrated materials at the nanoscale dimensions have emerged as the efficient means to utilize the material's potential in current and future technological applications, especially in photoelectrochemical energy-related applications. 1,[4][5][6][7][8][9]11 Such approaches and nanoscale architectures enabled integration of WO 3 -based materials in many of the current and emerging technologies including mechanical/chemical sensors, 1 photoelectrochemical cells (PECs), 3 displays, 3 variable reflectance mirrors, 4 chemical/ electrochemical sensors, 2,16 lithium batteries, 2,6 photocatalysis, and even photodetector materials, 4,5 electrochemical industry, 5 and environmental engineering. 6 For instance, in the design and development of PECs, nanoscale architectures of WO 3 regarded as an attractive photocatalyst for O 2 generation since it exhibits the desirable properties and phenomena.…”

“…Tungsten oxide (WO 3 ) exhibits quite interesting physical, chemical, electronic, and optical properties, which makes these materials interesting for a multitude of scientific and technological applications. − Recently, synthesis, characterization, and performance evaluation of low-dimensional structures, including nanorods to ultrathin films, of WO 3 are attracting the interest of the scientific community largely due to their novel properties and potential applications in numerous technologies. − In fact, the design and development of novel architectures of stoichiometric or nonstoichiometric WO 3 and their hydrated materials at the nanoscale dimensions have emerged as the efficient means to utilize the material’s potential in current and future technological applications, especially in photoelectrochemical energy-related applications. ,− , Such approaches and nanoscale architectures enabled integration of WO 3 -based materials in many of the current and emerging technologies including mechanical/chemical sensors, photoelectrochemical cells (PECs), displays, variable reflectance mirrors, chemical/electrochemical sensors, , lithium batteries, , photocatalysis, and even photodetector materials, , electrochemical industry, and environmental engineering . For instance, in the design and development of PECs, nanoscale architectures of WO 3 regarded as an attractive photocatalyst for O 2 generation since it exhibits the desirable properties and phenomena.…”