本篇研究主要探討氧化鋅-還原型氧化石墨烯複合材料薄膜應用於室溫下感測二氧化氮氣體，首先使用旋轉塗佈法製備氧化鋅-氧化石墨烯複合材料薄膜，接著利用退火熱處理形成氧化鋅-還原型氧化石墨烯複合材料薄膜，其製程方式簡單以及擁有低成本之優勢。藉由改變摻雜氧化鋅的含量，改善氣體感測器之響應度。由實驗結果得知，摻雜比例為ZnO/GO=0.08的氧化鋅-還原型氧化石墨烯氣體感測器在室溫下對二氧化氮氣體擁有最佳響應度，當二氧化氮氣體濃度為100 ppm時，其響應度為45%，摻雜比例為ZnO/GO=0.08的氧化鋅-還原型氧化石墨烯氣體感測器在室溫下量測不同濃度二氧化氮時，亦具備良好的線性趨勢、響應時間、恢復時間以及氣體選擇性之優點，當退火時間增加至2小時，其在室溫下對100 ppm 二氧化氮之響應度為48%。

In this study, the high performances room temperature nitrogen dioxide (NO2) gas sensors were fabricated using zinc oxide-reduced graphene oxide (ZnO-rGO) composite films as sensing materials. The ZnO-rGO composite films were synthesized by annealing the zinc oxide-graphene oxide (ZnO-GO) composite films in Ar flow at 300℃ for 1 h which were prepared by spin-coating. Moreover, the ZnO-rGO composite films possessed several advantages, including easy fabrication and low cost. By varying the doping amount of ZnO, the response of gas sensors would be enhanced. According to the experimental results, the gas sensors using ZnO-rGO composite films which the weight ratio (ZnO/GO) was 0.08 as sensing materials exhibited the better NO2 sensing response at room temperature. The ZnO-rGO gas sensors (ZnO/GO=0.08) exhibited the sensing response of 45% under 100 ppm NO2 gas. Moreover, the ZnO-rGO gas sensors (ZnO/GO=0.08) which annealed in Ar flow at 300℃ for 2 h and 3 h possessed the gas response of 48% and 42% under 100 ppm NO2. The performances of the ZnO-rGO gas sensors (ZnO/GO=0.08) sensing different concentration of NO2 at room temperature not only had good linearly curve but also exhibited other advantages such as good response time, recovery time, and selectivity.

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