In Situ Growth of NiO@SnO2 Hierarchical Nanostructures for High Performance H2S Sensing
In Situ Growth of NiO@SnO2 Hierarchical Nanostructures for High Performance H2S Sensing
复制标题
用于高性能 H2S 传感的 NiO@SnO2 分层纳米结构的原位生长
DOI：
10.1021/acsami.9b13001
复制
发表时间：
2019-11-27
影响因子：
9.5
通讯作者：
Qin, Sujie
中科院分区：
文献类型：
--
作者：
Liu, Lin;Wang, Yingyi;Qin, Sujie
具有大比表面积的异质结构金属氧化物是构建高性能气体传感器的关键。然而，使用浆料涂覆和丝网印刷方法来制造气体传感器不能导致传感器的高均匀性和再现性。在这里，通过化学浴沉积法而不是印刷涂布和浆料涂布方法，在陶瓷微芯片上原位生长由SnO 2纳米针（NiO@SnO2）装饰的NiO球来检测H2S。通过改变NiO@SnO2分级纳米结构的生长时间来调整其形貌和组成，以优化其传感性能。NiO@SnO2 HNS（2 h）对1 ppm H2S的响应比纯NiO纳米片高23倍以上，比纯SnO 2纳米片高17倍。这种显著的增强归因于NiO@SnO2 HNS的大表面积以及SnO 2和NiO的异质界面处的p-n异质结。在SnO 2和NiO的异质界面处的耗尽层（W-SnO 2和W-NiO）的变化很大程度上取决于靶气体的性质（例如，吸电子性（NO2）或供电子性（H2S））。
Heterostructured metal oxides with large specific surface area are crucial for constructing gas sensors with high performance. However, using slurry-coating and screen-printing methods to fabricate gas sensors cannot result in high uniformity and reproducibility of the sensors. Here, NiO nanowalls decorated by SnO2 nanoneedles (NiO@SnO2) were in situ grown on ceramic microchips via a chemical bath deposition method to detect H2S instead of print-coating and slurry-coating methods. The morphologies and compositions of the NiO@SnO2 hierarchical nanostructures (HNSs) were well tuned by varying the growth time of the NiO@SnO2 HNSs to optimize the sensing performance. The response of the NiO@SnO2 HNSs (2 h) to 1 ppm of H2S was over 23-fold higher than that of the pure NiO nanowalls and 17-fold higher than that of the pure SnO2 nanosheets. This dramatic enhancement is attributed to the large surface area of the NiO@SnO2 HNSs and the p-n heterojunction at the heterointerface of SnO2 and NiO. The variation in the depletion layers (W-SnO2 and W-NiO) at the heterointerface of SnO2 and NiO greatly depends on the properties of the target gases (e.g., electron-withdrawing property (NO2) or electron-donating property (H2S)).