Highly Sensitive Ammonia Gas Sensors at Room Temperature Based on the Catalytic Mechanism of N,C Coordinated Ni Single-Atom Active Center  

作　　者：Wenjing Quan Jia Shi Min Zeng Wen Lv Xiyu Chen Chao Fan Yongwei Zhang Zhou Liu Xiaolu Huang Jianhua Yang Nantao Hu Tao Wang Zhi Yang 

机构地区：[1]National Key Laboratory of Advanced Micro and Nano Manufacture Technology,Shanghai Jiao Tong University,Shanghai 200240,People’s Republic of China [2]Department of Micro/Nano Electronics,School of Electronic Information and Electrical Engineering,Shanghai Jiao Tong University,Shanghai 200240,People’s Republic of China [3]Shanghai Key Laboratory of Intelligent Sensing and Detection Technology,School of Mechanical and Power Engineering,East China University of Science and Technology,Shanghai 200237,People’s Republic of China

出　　处：《Nano-Micro Letters》2024年第12期515-531,共17页纳微快报（英文版）

基　　金：supported by the National Key Research and Development Program of China(2022YFB3205500);the National Natural Science Foundation of China(62371299,62301314 and 62101329);the China Postdoctoral Science Foundation(2023M732198);the Natural Science Foundation of Shanghai(23ZR1430100);supported by the Center for High-Performance Computing at Shanghai Jiao Tong University.

摘　　要：Significant challenges are posed by the limitations of gas sensing mechanisms for trace-level detection of ammonia(NH3).In this study,we propose to exploit single-atom catalytic activation and targeted adsorption properties to achieve highly sensitive and selective NH3 gas detection.Specifically,Ni singleatom active sites based on N,C coordination(Ni-N-C)were interfacially confined on the surface of two-dimensional(2D)MXene nanosheets(Ni-N-C/Ti_(3)C_(2)Tx),and a fully flexible gas sensor(MNPE-Ni-N-C/Ti_(3)C_(2)Tx)was integrated.The sensor demonstrates a remarkable response value to 5 ppm NH3(27.3%),excellent selectivity for NH3,and a low theoretical detection limit of 12.1 ppb.Simulation analysis by density functional calculation reveals that the Ni single-atom center with N,C coordination exhibits specific targeted adsorption properties for NH3.Additionally,its catalytic activation effect effectively reduces the Gibbs free energy of the sensing elemental reaction,while its electronic structure promotes the spill-over effect of reactive oxygen species at the gas-solid interface.The sensor has a dual-channel sensing mechanism of both chemical and electronic sensitization,which facilitates efficient electron transfer to the 2D MXene conductive network,resulting in the formation of the NH3 gas molecule sensing signal.Furthermore,the passivation of MXene edge defects by a conjugated hydrogen bond network enhances the long-term stability of MXene-based electrodes under high humidity conditions.This work achieves highly sensitive room-temperature NH3 gas detection based on the catalytic mechanism of Ni single-atom active center with N,C coordination,which provides a novel gas sensing mechanism for room-temperature trace gas detection research.

关 键 词：Gas sensor Single atom Catalytic activation Targeted adsorption End-sealing passivation 

分 类 号：TQ426[化学工程] TP212[自动化与计算机技术—检测技术与自动化装置]