ساخت و بررسي حسگر مقاومتي لايه‌نازك SnO₂ با كمك تابش فرابنفش براي تشخيص گاز هيدروژن

Hydrogen has emerged as a promising clean energy carrier due to its high energy density an‎d zero carbon emission during utilization. However, the high flammability an‎d wide explosive range of hydrogen require the development of reliable, sensitive, an‎d low-power hydrogen detection systems. In this study, UV-assisted SnO₂ thin-film resistive gas sensors were fabricated on glass substrates using the pulsed laser deposition (PLD) technique for hydrogen sensing applications. The influence of UV irradiation duration on the hydrogen sensing performance of SnO₂ thin films was systematically investigated. The fabricated sensors were subjected to different UV treatment times, an‎d their sensing characteristics were eva‎luated through dynamic resistance measurements under various operating conditions. The effect of UV irradiation duration on the surface activation an‎d hydrogen sensing behavior of SnO₂ was investigated by comparing the response characteristics of different samples. The sensing performance of the fabricated SnO₂ sensors was analyzed by eva‎luating dynamic response behavior, operating temperature dependence, hydrogen concentration effects, selec‎tivity, an‎d humidity influence. The results demonstrated that UV irradiation significantly affects the sensing characteristics of SnO₂ thin films by modifying surface electronic states, enhancing oxygen adsorption behavior, an‎d improving the interaction between hydrogen molecules an‎d chemically adsorbed oxygen species. The hydrogen sensing mechanism was explained based on the surface charge transfer model of n-type SnO₂ semiconductors. In air atmosphere, oxygen adsorption on the SnO₂ surface leads to electron depletion an‎d an increase in sensor resistance. Upon exposure to hydrogen, the reaction between hydrogen molecules an‎d adsorbed oxygen species releases electrons back into the conduction ban‎d, resulting in resistance modulation. The obtained results confirm that UV treatment is an effective approach for improving the hydrogen sensing performance of SnO₂ thin-film sensors. The combination of PLD-grown SnO₂ films an‎d UV-induced surface activation provides a promising strategy for developing efficient resistive hydrogen sensors with improved sensing characteristics.

مهدي رنجبر

سميه كياني

كيومرث زرگوش , پيمان صاحب سرا