Single stranded 1D-helical Cu coordination polymer for ultra-sensitive ammonia sensing at room temperature

Abstract

With the increasing demand for ammonia applications, there is a significant focus on improving NH₃ detection performance at room temperature. In this study, we introduce a groundbreaking NH₃ gas sensor based on Cu(I)-based coordination polymers, featuring semiconducting, single stranded 1D-helical nanowires constructed from Cu–Cl and N-methylthiourea (MTCP). The MTCP demonstrates an exceptional response to NH₃ gas (>900% at 100 ppm) and superior selectivity at room temperature compared to current materials. The interaction mechanism between NH₃ and the MTCP sensor is elucidated through a combination of empirical results and computational calculations, leveraging a crystal-determined structure. This reveals the formation of NH₃–Cu and NH₃–H₃C complexes, indicative of a thermodynamically favorable reaction. Additionally, Ag-doped MTCP exhibits higher selectivity and a response over two times greater than the original MTCP, establishing it as a prominent NH₃ detection system at room temperature.