Bao Jiading, Wang Ye, Zhu Houbai, Yu Jiabing, Yang Xuan, Chen Xianping
Faculty of Mechanical and Electrical Engineering, Guilin University of Electronic Technology, Guangxi Key Laboratory of Manufacturing Systems and Advanced Manufacturing Technology, 541004 Guilin, China.
College of Optoelectronic Engineering and Key Laboratory of Optoelectronic Technology & Systems Education Ministry of China, Chongqing University, 400044 Chongqing, China.
Langmuir. 2024 Sep 9. doi: 10.1021/acs.langmuir.4c02295.
Two-dimensional materials, owing to their unique physical properties and high surface area, play a crucial role in intelligent sensing, particularly in the domain of atmospheric pollutant monitoring. In this work, we have extensively investigated the gas-sensing capabilities of the HfNBr monolayer for ammonia detection by introducing point defects, utilizing density functional theory and nonequilibrium Green's function calculations. Upon the introduction of point defects, the adsorption energy of HfNBr monolayers for ammonia significantly increased (from -0.162 to -1.257 eV), indicating a markedly strengthened affinity. To further elucidate the sensing mechanism, we conducted an in-depth investigation into the charge transfer dynamics, the density of states, and the charge density difference between the adsorbent and the adsorbate. Besides, we employed the NEGF method to evaluate the changes in the current-voltage characteristics of the HfNBr monolayer before and after adsorption, which revealed a remarkable change in the apparent resistance, thereby demonstrating excellent sensitivity. The exceptional performance of the HfNBr monolayer toward NH demonstrates its significant value in practical applications for ammonia detection.
二维材料因其独特的物理性质和高比表面积，在智能传感中发挥着关键作用，特别是在大气污染物监测领域。在这项工作中，我们利用密度泛函理论和非平衡格林函数计算，通过引入点缺陷，广泛研究了HfNBr单层对氨的气敏性能。引入点缺陷后，HfNBr单层对氨的吸附能显著增加（从-0.162 eV增加到-1.257 eV），表明亲和力明显增强。为了进一步阐明传感机制，我们深入研究了电荷转移动力学、态密度以及吸附剂与吸附质之间的电荷密度差。此外，我们采用非平衡格林函数方法评估了吸附前后HfNBr单层电流-电压特性的变化，结果表明表观电阻有显著变化，从而证明了其优异的灵敏度。HfNBr单层对NH的优异性能表明其在氨检测的实际应用中具有重要价值。
