Programmed Synthesis of Sn ₃ N ₄ Nanoparticles via a Soft Chemistry Approach with Urea: Application for Ethanol Vapor Sensing

Metal nitrides are a significant class of multifunctional materials that have attracted a huge and ever-increasing interest for their new structural and redox chemical, as well as physical, characteristics. In this work, we present a designed synthesis of Sn 3 N 4 nanoparticles through a soft urea route for the first time. The strategy includes the synthesis of gel-like tin–urea precursor and subsequent transformation to Sn 3 N 4 nanoparticles via thermal treatment of the as-prepared precursor under NH 3 flow. Various techniques were employed to characterize the structure and morphology of the as-prepared Sn 3 N 4 samples. When innovatively utilized as sensing material for a gas sensor, Sn 3 N 4 nanoparticles exhibited high sensitivity, excellent cyclability, and long-term stability to ethanol at the operating temperature of 120 °C, which is lower than those of metal oxide-based ethanol sensors. This research work provides an efficient method for preparing Sn 3 N 4 nanoparticles that are promising sensing materials for ethanol gas sensors.