Ag@SnO2/CsPbBr3 nanocomposite gas sensor for well-behaved low-concentration ethanolamine sensing at room temperature

Abstract

It is a novel-effective process for realizing high-efficiency sensing and continuous gas monitoring by introducing precious metals into metal–oxide–semiconductors (MOSs). In this study, Ag is exploited to prepare surface functionalized SnO2 nanoparticles (NPs) and innovative xAg@SnO2/CsPbBr3, activating and catalyzing the gas sensing reactions on semiconductors. The results show that the precious metal Ag NPs promote the directional transport of carriers, thus improving the gas sensing performances. In addition, innovative xAg@SnO2/CsPbBr3 composites originated from Ag@SnO2 NPs and 3-mercaptopropionic acid treated all-inorganic perovskite CsPbBr3 are constructed to further accelerate electron transfer on heterointerfaces, enabling continuous and efficient monitoring of ethanolamine (EA) at room temperature. The sensing properties of Ag@SnO2/CsPbBr3 on various volatile organic compounds are investigated. Compared with pure CsPbBr3, the EA response of as-prepared 2Ag@SnO2/CsPbBr3 is obviously improved by about sevenfold. The response/recovery time is greatly shortened, besides the good stability. Another interesting result for xAg@SnO2/CsPbBr3 is the lower limit of detection of 44.43 ppb. The work demonstrates that Ag modification facilitates the adsorption/desorption rate and the response. Furthermore, the catalytic activation of noble metal Ag NPs and the synergistic interaction of SnO2/CsPbBr3 nano-heterojunctions promote EA sensing performances at room temperature.