High-performance and wearable hazardous gases sensor based on n-n heterojunction film of NGO and tetrakis(1-pyrenyl)porphyrin

High-performance and wearable hazardous gases sensor based on n-n heterojunction film of NGO and tetrakis(1-pyrenyl)porphyrin

The popularity of "Internet of Things" and portable electronic devices creates unprecedented demands for wearable gas sensors with excellent performance. In this study, the flexible n-n heterojunction film is firstly produced from metalloporphyrin complex 5,10,15,20-tetrakis(1-pyrenyl) porphyrin cobalt (II) (CoTPyrP) and nitrogen-doped graphene oxide (NGO) film, using solution-processing quasi-Langmuir-Shafer (QLS) method and employed as the electrochemical identification layer for the wearable sensor. Thanks to the attractive electrontransfer properties from porphyrin to NGO, and the local regulation of electron transport by N and C atoms with different electronegativity on NGO, the resulting sensor shows good responses to NO2, SO2, NH3, H2S gases with the low detection limit (LOD) of 6, 74, 113 and 178 ppb, respectively. The uniform and compact structure of the heterojunction films provide excellent mechanical flexibility and suppress the penetration of gases into the film to obtain fast recovery speed. In addition, a sensor array consisting of NGO/CoTPyrP heterojunction and CoTPyrP film sensor is established, achieving selective identification of four hazardous gases. The present work provides potential application for hazardous gases identification in actual systems, and proposes an effective method to develop new flexible n-n heterojunctions for wearable gas sensors.

“物联网”和便携式电子设备的普及对性能优异的可穿戴式气体传感器产生了前所未有的需求。在本研究中，首先利用溶液处理准朗缪尔 - 谢弗（QLS）方法，由金属卟啉配合物5,10,15,20 - 四（1 - 芘基）卟啉钴（II）（CoTPyrP）和氮掺杂氧化石墨烯（NGO）薄膜制备出柔性n - n异质结薄膜，并将其用作可穿戴式传感器的电化学识别层。由于卟啉到NGO具有吸引人的电子转移特性，以及NGO上不同电负性的N和C原子对电子传输的局部调节，所得传感器对NO₂、SO₂、NH₃、H₂S气体表现出良好的响应，其检测限（LOD）分别为6、74、113和178 ppb。异质结薄膜均匀且致密的结构提供了优异的机械柔韧性，并抑制气体渗透到薄膜中，从而获得快速的恢复速度。此外，建立了一个由NGO/CoTPyrP异质结和CoTPyrP薄膜传感器组成的传感器阵列，实现了对四种有害气体的选择性识别。本研究为实际系统中有害气体的识别提供了潜在应用，并提出了一种开发用于可穿戴式气体传感器的新型柔性n - n异质结的有效方法。