Zhu Li-Yuan, Yuan Kai-Ping, Yang Jia-He, Hang Cheng-Zhou, Ma Hong-Ping, Ji Xin-Ming, Devi Anjana, Lu Hong-Liang, Zhang David Wei
State Key Laboratory of ASIC and System, Shanghai Institute of Intelligent Electronics & Systems, School of Microelectronics, Fudan University, 200433 Shanghai, China.
Inorganic Materials Chemistry, Ruhr-University Bochum, 44780 Bochum, Germany.
Microsyst Nanoeng. 2020 May 4;6:30. doi: 10.1038/s41378-020-0142-6. eCollection 2020.
Highly sensitive and selective hydrogen sulfide (HS) sensors based on hierarchical highly ordered SnO nanobowl branched ZnO nanowires (NWs) were synthesized via a sequential process combining hard template processing, atomic-layer deposition, and hydrothermal processing. The hierarchical sensing materials were prepared in situ on microelectromechanical systems, which are expected to achieve high-performance gas sensors with superior sensitivity, long-term stability and repeatability, as well as low power consumption. Specifically, the hierarchical nanobowl SnO@ZnO NW sensor displayed a high sensitivity of 6.24, a fast response and recovery speed (i.e., 14 s and 39 s, respectively), and an excellent selectivity when detecting 1 ppm HS at 250 °C, whose rate of resistance change (i.e., 5.24) is 2.6 times higher than that of the pristine SnO nanobowl sensor. The improved sensing performance could be attributed to the increased specific surface area, the formation of heterojunctions and homojunctions, as well as the additional reaction between ZnO and HS, which were confirmed by electrochemical characterization and band alignment analysis. Moreover, the well-structured hierarchical sensors maintained stable performance after a month, suggesting excellent stability and repeatability. In summary, such well-designed hierarchical highly ordered nanobowl SnO@ZnO NW gas sensors demonstrate favorable potential for enhanced sensitive and selective HS detection with long-term stability and repeatability.
通过结合硬模板处理、原子层沉积和水热法的顺序工艺，合成了基于分级高度有序的SnO纳米碗分支ZnO纳米线（NWs）的高灵敏度和选择性硫化氢（HS）传感器。在微机电系统上原位制备了分级传感材料，有望实现具有卓越灵敏度、长期稳定性和重复性以及低功耗的高性能气体传感器。具体而言，分级纳米碗SnO@ZnO NW传感器在250℃检测1 ppm HS时显示出6.24的高灵敏度、快速的响应和恢复速度（分别为14秒和39秒）以及优异的选择性，其电阻变化率（即5.24）比原始SnO纳米碗传感器高2.6倍。传感性能的提高可归因于比表面积的增加、异质结和同质结的形成以及ZnO与HS之间的额外反应，这通过电化学表征和能带排列分析得到证实。此外，结构良好的分级传感器在一个月后保持稳定性能，表明具有出色的稳定性和重复性。总之，这种精心设计的分级高度有序纳米碗SnO@ZnO NW气体传感器在增强灵敏和选择性HS检测以及长期稳定性和重复性方面显示出良好的潜力。
