Shao Shaofeng, Xie Chunyu, Zhang Lei, Wei Song, Kim Hyoun Woo, Kim Sang Sub
Institute of Advanced Materials and Flexible Electronics (IAMFE), School of Chemistry and Materials Science, Nanjing University of Information Science & Technology, 210044 Nanjing, China.
Division of Materials Science and Engineering, Hanyang University, Seoul 04763, Republic of Korea.
ACS Appl Mater Interfaces. 2021 Mar 31;13(12):14447-14457. doi: 10.1021/acsami.0c20566. Epub 2021 Mar 19.
It is an effective strategy to enhance the sensitivity of semiconductor metal oxides (SMOs) being sensitized with CsPbI nanocrystals (NCs) by adjusting the heterostructure between CsPbI and SMO nanomaterials. In this work, for the first time, a porous 3D multiple-walled carbon nanotube (MWCNT) network uniformly coated with SnO quantum nanoparticles (QNPs) and CsPbI nanocrystals were prepared via a simple solvent vapor-induced self-assembly method. The fabricated CsPbI-SnO/MWCNT nanocomposite with vapor-induced self-assembly exhibits superior stability against the moisture as well as an excellent sensing response. The results imply that the rational design of the metal halide perovskite NC/SMO heterostructure can not only improve the stability but also meet the requirements of sensing application. The self-assembled SnOQNP/MWCNT can facilitate the dispersion of small-sized nanoparticles and efficaciously prevent the detachment of CsPbI. Compared with pristine SnO and SnO/MWCNT sensors, the CsPbI-modified SnO/MWCNT nanostructure exhibited a remarkable sensitivity of 39.2 for 0.2 ppm NH, rapid response/recovery time of 17/18 s, and excellent selectivity towards NH. In particular, we applied machine learning methods, including principal component analysis (PCA) and support vector machines (SVMs), to analyze the sensing performance of the CsPbI-SnO/MWCNT sensor and found that the combined effects of CsPbI-SnO/MWCNT heterointerfaces contributed to the improvement of selectivity of sensors. The excellent NH for sub-ppm level concentration is ascribed to the high sensing activity of the CsPbI NC-based heterojunction. This work may not only enrich the family of high-performance breath detection materials but also provide a good example for designing reasonable composite materials with specific properties in the field of metal halide perovskite/SMO heterojunctions.
通过调整CsPbI与半导体金属氧化物（SMO）纳米材料之间的异质结构，是提高用CsPbI纳米晶体（NCs）敏化的半导体金属氧化物（SMOs）灵敏度的有效策略。在这项工作中，首次通过简单的溶剂蒸汽诱导自组装方法制备了均匀涂覆有SnO量子纳米颗粒（QNPs）和CsPbI纳米晶体的多孔3D多壁碳纳米管（MWCNT）网络。通过蒸汽诱导自组装制备的CsPbI-SnO/MWCNT纳米复合材料对水分具有优异的稳定性以及出色的传感响应。结果表明，合理设计金属卤化物钙钛矿NC/SMO异质结构不仅可以提高稳定性，还能满足传感应用的要求。自组装的SnO QNP/MWCNT可以促进小尺寸纳米颗粒的分散，并有效防止CsPbI的脱离。与原始的SnO和SnO/MWCNT传感器相比，CsPbI修饰的SnO/MWCNT纳米结构对0.2 ppm NH₃表现出39.2的显著灵敏度、17/18 s的快速响应/恢复时间以及对NH₃的优异选择性。特别是，我们应用了包括主成分分析（PCA）和支持向量机（SVM）在内的机器学习方法来分析CsPbI-SnO/MWCNT传感器的传感性能，发现CsPbI-SnO/MWCNT异质界面的综合作用有助于提高传感器的选择性。对于亚ppm级浓度的优异NH₃传感性能归因于基于CsPbI NC的异质结的高传感活性。这项工作不仅可以丰富高性能呼吸检测材料家族，还可以为在金属卤化物钙钛矿/SMO异质结领域设计具有特定性能的合理复合材料提供一个很好的例子。
