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–Shäfer (QLS) method and employed as the electrochemical identification layer for the wearable sensor. Thanks to the attractive electron-transfer 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，对性能卓越的可穿戴气体传感器产生了前所未有的需求。在这项研究中，柔性 nn 异质结薄膜首先由金属卟啉配合物 5,10,15,20-四（1-芘基）卟啉钴（II）（CoTPyrP）和氮掺杂氧化石墨烯（NGO）薄膜制成，使用溶液-处理准朗缪尔-谢弗 (QLS) 方法并用作可穿戴传感器的电化学识别层。由于从卟啉到 NGO 的有吸引力的电子转移特性，以及在 NGO 上具有不同电负性的 N 和 C 原子对电子传输的局部调节，所得传感器对 NO ₂、SO ₂、NH ₃、H ₂显示出良好的响应S 气体的低检测限 (LOD) 分别为 6、74、113 和 178 ppb。异质结薄膜均匀致密的结构提供了优异的机械柔韧性，并抑制了气体渗入薄膜中以获得快速恢复速度。此外，还建立了由NGO/CoTPyrP异质结和CoTPyrP薄膜传感器组成的传感器阵列，实现了四种有害气体的选择性识别。目前的工作为实际系统中危险气体的识别提供了潜在的应用，并提出了一种有效的方法来开发用于可穿戴气体传感器的新型柔性 nn 异质结。