Enhancement of H2-sensing Properties of F-doped SnO2 Sensor by Surface Modification with SiO2

Sensors

Chi-Hwan Han¹  Sang-Do Han¹ 

[1] Photo- & Electro-Materials Research Center, Korea Institute of Energy Research, 71-2 Jangdong Yusung, Daejeon 305-343, Korea

关键词: F-doped SnO₂ sensor;    Surface modification;    Sodium silicate;    H₂ sensitivity;    MEMS technology;   

DOI  :  10.3390/s6050492

来源: mdpi

【 摘 要 】

Effects of surface chemical modification with sodium silicate on the gas-sensing properties of F-doped SnO₂ gas sensor designed and fabricated employing micro-electro mechanical system (MEMS) technology were investigated. Gas sensing properties of the sensor were checked against combustible gases like H₂, CO, CH₄ and C₃H₈ at a heater voltage of 0.7 V. The H₂ sensitivity of the surface modified F-doped SnO₂ micro sensor markedly increased and reached S = 175 which was found to be about 40 times more than that of unmodified sensor (S = ∼ 4.2). The increase in the sensitivity is discussed in terms of increased resistivity and reduced permeation of gaseous oxygen into the underlying sensing layer due to the surface modification of the sensor. The present micro-hydrogen sensor with enhanced sensitivity due to SiO₂ incorporation is a low energy consuming portable sensor module that can be mass-produced using MEMS technology at low cost.

【 授权许可】

Unknown   
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