Hu Xiafen, Li Xiang, Yang Huimin, Xu Chengjia, Xiong Weiqiang, Guo Xiang, Xie Changsheng, Zeng Dawen
The State Key Laboratory of Materials and Processing Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China.
Hubei Sanjiang Aerospace Jianghe Chemical Technology Co., Ltd. of China, Yichang 444200, People's Republic of China.
ACS Sens. 2022 Jul 22;7(7):1894-1902. doi: 10.1021/acssensors.2c00487. Epub 2022 Jun 23.
Defect engineering has received extensive attention as an effective method to tune the gas sensing properties of semiconductor materials. Here, defective WO (D-WO) nanosheets were obtained by a simple hydrogenation process with a detection limit as low as 5 ppb for dimethyl trisulfide (DMTS) and a response of 2.3 times that of the initial WO nanosheets to 100 ppb DMTS. Importantly, X-ray photoelectron spectroscopy and Raman spectroscopy confirmed the partial loss of oxygen atoms in D-WO nanosheets, and density functional theory calculations found that the W sites near the oxygen defect showed higher adsorption energy for DMTS and transferred more electrons during the gas interaction, indicating that the active W site caused by oxygen atom loss can effectively enhance the reactivity of two-dimensional WO nanosheets. Different from the traditional oxygen defect model, this work reveals the positive effect of active metal sites on gas sensing for the first time, which is expected to provide an effective reference for the sensing application of defect engineering in metal oxides.
缺陷工程作为一种调节半导体材料气敏性能的有效方法受到了广泛关注。在此，通过简单的氢化过程制备了缺陷型WO（D-WO）纳米片，其对二甲基三硫化物（DMTS）的检测限低至5 ppb，对100 ppb DMTS的响应是初始WO纳米片的2.3倍。重要的是，X射线光电子能谱和拉曼光谱证实了D-WO纳米片中氧原子的部分损失，密度泛函理论计算发现氧缺陷附近的W位点对DMTS表现出更高的吸附能，并且在气体相互作用过程中转移了更多电子，这表明氧原子损失导致的活性W位点可以有效增强二维WO纳米片的反应活性。与传统的氧缺陷模型不同，这项工作首次揭示了活性金属位点对气敏的积极作用，有望为缺陷工程在金属氧化物传感应用中提供有效参考。
