Mn²⁺-Doped CsPbCl₃ Nanocrystals for Ammonia Gas Sensing

All inorganic perovskite nanocrystals (NCs) have emerged as versatile materials for gas sensing due to their tunable optical properties and high surface-to-volume ratios. However, CsPbCl 3 has limitations when it comes to gas sensing. In this study, we explore the potential of Mn 2+ -doped CsPbCl 3 NCs as a room-temperature sensing platform for ammonia (NH 3 ) gas detection. By incorporating Mn 2+ dopants into the CsPbCl 3 lattice, we enhance the sensitivity of the NCs to NH 3 gas. Additionally, NH 3 molecules interact with the NCs, leading to the dynamic passivation of Cl – vacancies. We systematically investigate the sensing performance of Mn:CsPbCl 3 NCs by using varying NH 3 concentrations, different exposure conditions, and exposure cycles, revealing a reversible and concentration-dependent response. The sensor based on Mn 2+ -doped CsPbCl 3 NCs has good selectivity for NH 3 at room temperature, showing a higher sensitivity (2.12 at 100 ppm) than the pure CsPbCl 3 NC sensor (1.10 at 100 ppm), and good repeatability. The unique optical properties of Mn:CsPbCl 3 NCs, coupled with their responsiveness to NH 3, make them promising candidates for developing efficient and cost-effective room-temperature NH 3 gas sensors. This work contributes to the advancement of NC-based gas sensing technologies and highlights the potential of Mn-doped CsPbCl 3 NCs in environmental monitoring, industrial safety, and other gas sensing applications.