Covalent Organic Framework-Enhanced Metal Halide Perovskites for Selective and Sensitive Gas Sensing
Wen Ye1,2, Meng Li3, Guixiang Li4,5, Lihua Jiang1, Shun Tian5, Shihong Dong6, Qingfeng Xu1, Dongyun Chen1(陈冬赟)*, Mohammad Khaja Nazeeruddin5,7*, Paul J. Dyson5*, Antonio Abate4,8,9*, Jian-Mei Lu1（路建美）*
1College of Chemistry Chemical Engineering and Materials Science Collaborative Innovation Center of Suzhou Nano Science and Technology National United Engineering Laboratory of Functionalized Environmental Adsorption Materials Soochow University Suzhou215123, China
2Key Laboratory of Intelligent Optoelectronic Devices and Chips of Jiangsu Higher Education Institutions School of Physical Science and Technology Suzhou University of Science and Technology Suzhou 215009, China
3Key Lab for Special Functional Materials of Ministry of Education, School of Nanoscience and Materials EngineeringHenan UniversityKaifeng 475004, China
4Helmholtz-Zentrum Berlin für Materialien und Energie GmbH14109 Berlin,Germany
5Institute of Chem. Sciences and Engineering École Polytechnique Fédérale de Lausanne (EPFL) Lausanne CH-1015, Switzerland
6Suzhou Shijing Technology Co., Ltd58 Jinrui Road, Suzhou 215137, China
7Mechanical and Energy Engineering DepartmentCollege of EngineeringImam Abdulrahman Bin Faisal UniversityDammam 34212, Saudi Arabia
8Department of Chemistry Bielefeld University, Universitätsstraße 2533615 Bielefeld, Germany
9Department of Chemical Materials and Production Engineering University of Naples Federico II.Naples Piazzale Vincenzo Tecchio 80, Naples 80125, Italy
Adv. Funct. Mater. 2025, 35, 2418897
Abstract: Solution-processed lead-free halide perovskite gas sensors possess low gas detection limits, offering promising alternatives to traditional metal oxide chemiresistors. However, halide perovskite chemiresistors often suffer from poor selectivity and durability due to a lack of coordinatively unsaturated surface metal ions and their sensitivity to humidity. To address these issues, a general strategy is presented in which the Cs2PdBr6 perovskite surface is coated with covalent organic framework (COF) to provide hybrid sensor materials that are highly sensitive to specific gases and demonstrate excellent stability under real-working conditions. The hybrid chemiresistors demonstrate high sensitivity and controllable selectivity toward NO2 or NH3 gases. Specifically, TAPB–PDA@Cs2PdBr6 achieves a detection limit of 10 ppb for NO2, the lowest value reported for a perovskite-based gas sensor, maintaining its performance after continuous exposure to ambient air for several weeks. In contrast, COF-5@Cs2PdBr6 shows high selectivity to NH3 and has a detection limit of 40 ppb. Structural and spectroscopic characterization combined with mechanistic studies provide molecular-level insights into the outstanding properties of these new hybrid sensor materials, which set a new benchmark in the field, i.e., surpassing the selectivity and sensitivity of conventional halide perovskite sensors.
Article information://doi.org/10.1002/adfm.202418897
