A stable and humidity resistant NH3 sensor based on luminous CsPbBr3 perovskite nanocrystals

Recent years, sensors based on perovskite nanomaterials have become one of the most interesting fields while their instability remains as one of the major obstacles for further advancement. In this work, for the first time, a facile and controllable strategy was proposed for in-situ growth of stable CsPbBr 3 nanocrystals in SiO 2 network on poly (vinylidene fluoride) membrane. The formation of SiO 2 network was triggered by the fast hydrolysis of (3-aminopropyl)triethoxysilane as the precursor. Characterization results including UV–vis, FTIR, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) indicate successful formation of CsPbBr 3 –SiO 2 nanocomposites. With the protection from SiO 2 network, the fluorescence intensity of CsPbBr 3 nanocrystals maintains 88.11% of initial intensity after 104 days in ambient environment and is stable during the humidity test (RH = 90%, for 30 min). CsPbBr 3 –SiO 2 nanocomposite based membrane can be applied as fluorescent sensors for NH 3 determination in high concentration range based on fluorescence quenching, which shows good linearity, accuracy, precision, and specificity toward NH 3 over common organic vapors. • With the protection from SiO 2 network, CsPbBr 3 nanocrystals own high stability in ambient environment. • Porous structure of PVDF membrane is beneficial for the nucleation and growth of CsPbBr 3 nanocrystals and gas adsorption. • The whole process of fabrication literally consists of stirring and dropping. • The sensor shows good selectivity, precision and accuracy for NH 3 sensing. • The sensor fills in the shortage of devices capable of high concentration monitoring of NH 3 .