Change in crystalline structure of W₁₈O₄₉nanowires induced by X-ray irradiation and its effects on field emission

Abstract

W18O49 nanowires were synthesized by thermal evaporation, and the effects of X-ray irradiation on their crystalline structure, chemical composition, and field emission properties were systematically investigated.

Identifying chemical and physical changes in wide-gap semiconductors using real-time and near ambient-pressure XPS

“…XPS studies of semiconductor surfaces can therefore in principle provide a correlation between the energy band profile and changes in the surface chemical environment induced, for example, by adsorption, heating and irradiation. 16–18 However, additional measurements are required to identify the influence of sample inhomogeneity and the influence of the measurement method such as final state effects, radiation damage and surface charging. 19,20…”

“…XPS studies of semiconductor surfaces can therefore in principle provide a correlation between the energy band prole and changes in the surface chemical environment induced, for example, by adsorption, heating and irradiation. [16][17][18] However, additional measurements are required to identify the inuence of sample inhomogeneity and the inuence of the measurement method such as nal state effects, radiation damage and surface charging. 19,20 Here we show how different mechanisms are responsible for the observed core level binding energy changes for a metal alloy and two wide-gap semiconductors when the temperature is cycled between room temperature and 600 C. Using real-time and near-ambient pressure XPS, where temperature and pressure are the only variables, the dominant physical and chemical effects are identied and corrected.…”

Defect Mediated W18O49 Nanorods Bundle for Nonenzymatic Amperometric Glucose Sensing Application

“…Guo et al, has reported a very high sensitivity and linearity range using Cu-coated nanoporous gold film as electrode for the glucose sensor but practically it is less feasible due to the uses of costly gold (Au) electrode for the growth of nanostructure . In particular, tungsten-based oxide semiconductors are exhibiting a versatile role in different applications viz., electrochemistry, catalysis, sensing, photovoltaic, and field emission due to its optimum band gap and environmental friendliness. − Among other tungsten-based oxides, W 18 O 49 with a monoclinic structure has been widely used because of its dominating defect yielding novel properties in the nanometer regime . It has an advantage of mixed valence tungsten ions, which makes it worthy for various different aspects like different kinds of gas sensing. − It is favored by the metal nanoparticles in terms of broad dispersion and strong bonding due to the oxygen vacant sites on its surface.…”

“…13−15 Among other tungsten-based oxides, W 18 O 49 with a monoclinic structure has been widely used because of its dominating defect yielding novel properties in the nanometer regime. 16 It has an advantage of mixed valence tungsten ions, which makes it worthy for various different aspects like different kinds of gas sensing. 17−19 It is favored by the metal nanoparticles in terms of broad dispersion and strong bonding due to the oxygen vacant sites on its surface.…”

X‐ray‐induced reduction of a surfactant/polyoxotungstate hybrid compound

“…Metal cations with no valence electrons (eg, Cr 6+ , Fe 3+ , Cu 2+ and Ce 4+ ) are highly susceptible to X‐ray‐induced photoreduction . X‐rays can also break bonds between adsorbed H 2 O and O 2 , forming reactive monoatomic ions that can react with the surface …”