A Plant‐inspired Light Transducer for High‐performance Near‐infrared Light Mediated Gas Sensing

Abstract Constructing near‐infrared light (NIR) light‐enhanced room temperature gas sensors is becoming more promising for practical application. In this study, learning from the structure and photosynthetic process of chlorophyll thylakoid membranes in plants, the first “Thylakoid membrane” structural formaldehyde (HCHO) sensor is constructed by matching the upconversion emission of the lanthanide‐doped upconversion nanoparticles (UCNPs) and the UV–vis adsorption of the as‐prepared nanocomposites. The NIR‐mediated sensor exhibits excellent performances, including ultra‐high response ( R a / R g = 2.22, 1 ppm), low practical limit of detection (50 ppb), reliable repeatability, high selectivity, and broadband spectral response. The practicality of the NIR‐mediated gas sensor is confirmed through the remote and external stimulation test. A study of sensing mechanism demonstrates that it is the UCNPs‐based light transducer produces more light‐induced oxygen species for gas response in the process of non‐radiative/radiative energy transfer, playing a key role in significantly improving the sensing properties of the sensor. The universality of NIR‐mediated gas sensors based on UCNPs is verified using ZnO, In 2 O 3, and SnO 2 systems. This work paves a way for fabricating high‐performance NIR‐mediated gas sensors and will expand the application fields of NIR light.