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arXiv · 1710.05998

Vanadium substitution: a simple and efficient way to improve UV sensing in ZnO

Tulika Srivastava·Gaurav Bajpai·Gyanendra Rathore·Sajal Biring·Somaditya Sen
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Abstract

UV sensing in pure ZnO is due to oxygen adsorption/desorption process from ZnO surface. Vanadium doping improves UV sensitivity of ZnO. Enhancement in UV sensitivity in doped ZnO is attributed to trapping and de-trapping of electrons at V4+ & V5+-related defect states. An extra electron in the V4+ state is excited under UV illumination while in absence of the same a trapping happens at the V5+ state. An insight to the mechanism is obtained by an analytic study of the response phenomenon.

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Tulika Srivastava, Gaurav Bajpai, Gyanendra Rathore, Sajal Biring, Somaditya Sen. 2017-10-16. Vanadium substitution: a simple and efficient way to improve UV sensing in ZnO. https://doi.org/10.1063/1.5012877

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