Weng Kaiyi, Peng Jiahe, Shi Zuhao, Arramel Arramel, Li Neng
State Key Laboratory of Silicate Materials for Architectures, School of Materials and Engineering, Wuhan University of Technology, Wuhan430070, China.
Shenzhen Research Institute of Wuhan University of Technology, Shenzhen518000, Guangdong, China.
ACS Omega. 2023 Jan 19;8(4):4261-4269. doi: 10.1021/acsomega.2c07492. eCollection 2023 Jan 31.
Ammonia (NH) detection at the early stage is an important precaution for human health and agricultural production. However, conventional sensing materials are difficult to achieve all the targeted operational performances such as low power consumption and high selectivity. MXenes are a type of graphene-like emergent material equipped with abundant surface sites benefiting gas-sensing applications. In the work, we discuss the sensing performance of TiCO to anticipate harmful and polluting NH gases by density functional theory and nonequilibrium Green's function. The adsorption geometry, charge difference density, and partial density of states are discussed to understand the nature of interactions between gas molecules and TiCO. The theoretical results show that only NH adsorbs onto the nanosheet through chemisorption. Then, a two-electrode TiCO-based gas sensor device is built to unravel the transport properties. Current under different bias voltages indicates the TiCO-based sensor could maintain extremely high sensitivity, demonstrating that TiCO has great potential for the NH sensor with high selectivity, excellent sensitivity, and low energy consumption. Upon external electric fields, the adsorption energy and charge transfer can be tuned effectively, suggesting that TiCO is a versatile agent as an ammonia-sensing material.
早期检测氨（NH₃）对人类健康和农业生产而言是一项重要的预防措施。然而，传统传感材料难以实现诸如低功耗和高选择性等所有目标操作性能。MXenes是一类类似石墨烯的新兴材料，具有丰富的表面位点，有利于气体传感应用。在这项工作中，我们通过密度泛函理论和非平衡格林函数来探讨Ti₃C₂O₂对有害和污染性NH₃气体的传感性能。我们讨论了吸附几何结构、电荷差分密度和态密度，以了解气体分子与Ti₃C₂O₂之间相互作用的本质。理论结果表明，只有NH₃通过化学吸附作用吸附到纳米片上。然后，构建了一种基于Ti₃C₂O₂的两电极气体传感器装置来揭示其传输特性。不同偏置电压下的电流表明，基于Ti₃C₂O₂的传感器能够保持极高的灵敏度，这表明Ti₃C₂O₂在具有高选择性、优异灵敏度和低能耗的NH₃传感器方面具有巨大潜力。在外部电场作用下，吸附能和电荷转移可以得到有效调节，这表明Ti₃C₂O₂作为一种氨传感材料是一种多功能介质。
