Highly Selective, ppb-Level Xylene Gas Detection by Sn<sup>2+</sup>-Doped NiO Flower-Like Microspheres Prepared by a One-Step Hydrothermal Method
Shaohe Lu,
Xuefeng Hu,
Hua Zheng,
Junwen Qiu,
Renbing Tian,
Wenjing Quan,
Xinjie Min,
Peng Ji,
Yewei Hu,
Suishi Cheng,
Wei Du,
Xiaoqiang Chen,
Beiliang Cui,
Xiaorong Wang,
Wei Zhang
Affiliations
Shaohe Lu
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 XinMofan Road, Nanjing 210009, China
Xuefeng Hu
School of Instrument Science and Opto-Electronics Engineering and Research Center for Sensor Science and Technology, Hefei University of Technology, No. 193 Tunxi Road, Hefei 230009, China
Hua Zheng
School of Electrical Engineering & Intelligentization, Dongguan University of Technology, No. 1 Daxue Rd, Dongguan 523808, China
Junwen Qiu
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 XinMofan Road, Nanjing 210009, China
Renbing Tian
School of Electrical Engineering & Intelligentization, Dongguan University of Technology, No. 1 Daxue Rd, Dongguan 523808, China
Wenjing Quan
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 XinMofan Road, Nanjing 210009, China
Xinjie Min
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 XinMofan Road, Nanjing 210009, China
Peng Ji
School of Electrical Engineering & Intelligentization, Dongguan University of Technology, No. 1 Daxue Rd, Dongguan 523808, China
Yewei Hu
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 XinMofan Road, Nanjing 210009, China
Suishi Cheng
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 XinMofan Road, Nanjing 210009, China
Wei Du
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 XinMofan Road, Nanjing 210009, China
Xiaoqiang Chen
State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, No. 5 XinMofan Road, Nanjing 210009, China
Beiliang Cui
Network Information Center, Nanjing Tech University, No. 5 XinMofan Road, Nanjing 210009, China
Xiaorong Wang
College of Electrical Engineering and Control Science, Nanjing Tech University, No. 5 XinMofan Road, Nanjing 210009, China
Wei Zhang
School of Instrument Science and Opto-Electronics Engineering and Research Center for Sensor Science and Technology, Hefei University of Technology, No. 193 Tunxi Road, Hefei 230009, China
Detecting xylene gas is an important means of avoiding human harm from gas poisoning. A precise measurement demands that the gas sensor used must have high sensitivity, high selectivity, and low working temperature. To meet these requirements, in this study, Sn2+-doped NiO flower-like microspheres (SNM) with different amounts of Sn2+ synthesized by a one-step hydrothermal process were investigated. The responses of gas sensors based on different Sn2+-doped NiO materials for various targeting gases were fully characterized. It was found that all of the synthesized materials exhibited the best gas response at a working temperature of 180 degrees, which was much lower than the previously reported working temperature range of 300−500 degrees. When exposed to 10 ppm xylene, the 8 at% Sn2+-doped NiO sensor (mol ratio) exhibited the highest response, with a value of 30 (Rg/Ra). More significantly, the detection limit of the 8 at% Sn2+-doped NiO sensor for xylene is down in the ppb level. The Sn2+-doped NiO material also exhibits excellent selectivity for other gases with long-term stability and repeatability. The significant improvement in the response to xylene can theoretically be attributed to a decrease in the intrinsic hole carrier concentration, higher amounts of adsorbed oxygen and active sites.
