Yang Min, Au Christian, Deng Guowei, Mathur Shaurya, Huang Qiuping, Luo Xiaolan, Xie Guangzhong, Tai Huiling, Jiang Yadong, Chen Chunxu, Cui Zheng, Liu Xiaoyang, He Chaozheng, Su Yuanjie, Chen Jun
College of Chemistry and Life Science, Sichuan Provincial Key Laboratory for Structural Optimization and Application of Functional Molecules, Chengdu Normal University, Chengdu 611130, China.
State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China.
ACS Appl Mater Interfaces. 2021 Nov 10;13(44):52850-52860. doi: 10.1021/acsami.1c10805. Epub 2021 Oct 29.
NiWO microflowers with a large surface area up to 79.77 m·g are synthesized in situ via a facile coprecipitation method. The NiWO microflowers are further decorated with multi-walled carbon nanotubes (MWCNTs) and assembled to form composites for NH detection. The as-fabricated composite exhibits an excellent NH sensing response/recovery time (53 s/177 s) at a temperature of 460 °C, which is a 10-fold enhancement compared to that of pristine NiWO. It also demonstrates a low detection limit of 50 ppm; the improved sensing performance is attributed to the porous structure of the material, the large specific surface area, and the p-n heterojunction formed between the MWNTs and NiWO. The gas sensitivity of the sensor based on daisy-like NiWO/MWCNTs shows that the sensor based on 10 mol % (MWN10) has the best gas sensitivity, with a sensitivity of 13.07 to 50 ppm NH at room temperature and a detection lower limit of 20 ppm. NH, CO, NO, SO, CO, and CH are used as typical target gases to construct the NiWO/MWCNTs gas-sensitive material and study the research method combining density functional theory calculations and experiments. By calculating the morphology and structure of the gas-sensitive material NiWO(110), the MWCNT load samples, the vacancy defects, and the influence law and internal mechanism of gas sensitivity were described.
通过简便的共沉淀法原位合成了表面积高达79.77 m²·g的NiWO微花。将NiWO微花进一步用多壁碳纳米管（MWCNTs）修饰并组装成用于NH检测的复合材料。所制备的复合材料在460℃温度下表现出优异的NH传感响应/恢复时间（53秒/177秒），与原始NiWO相比提高了10倍。它还显示出50 ppm的低检测限；传感性能的提高归因于材料的多孔结构、大比表面积以及MWNTs和NiWO之间形成的p-n异质结。基于雏菊状NiWO/MWCNTs的传感器的气敏性表明，基于10 mol%（MWN10）的传感器具有最佳气敏性，在室温下对50 ppm NH的灵敏度为13.07，检测下限为20 ppm。以NH、CO、NO、SO₂、CO和CH₄作为典型目标气体来构建NiWO/MWCNTs气敏材料，并研究结合密度泛函理论计算和实验的研究方法。通过计算气敏材料NiWO(110)、MWCNT负载样品的形貌和结构，描述了空位缺陷以及气敏性的影响规律和内在机制。
