Enabling selective, room-temperature gas detection using atomically dispersed Zn

Abstract Atomically dispersed metal catalysts (AMC) provide superb catalytic performance and 100 % atom utilization. AMC provide an almost perfect solution to the limitations of poor selectivity and high power consumption in semiconductor gas sensor applications. Herein, we report the synthesis of AMC ZnNC materials and their application as highly selective room temperature gas sensors for the first time. Various characterization methods including scanning transmission electron microscopy and X-ray absorption spectroscopy corroborate the presence of atomically dispersed Zn with ZnNC2 coordination. As a sample of AMC for gas detection, the AMC ZnNC2-based sensor has 25 % response to 1500 ppm ethanol (C2H5OH) at room temperature (∼25 °C) with excellent selectivity. Density functional theory calculations revealed that ethanol was chemically absorbed on ZnNC2 by forming a strong Zn-O bond, leading to obvious charge transfer from ethanol to ZnNC2. The sensor response can be attributed to the chemical adsorption of ethanol molecules rather than a redox reaction on the ZnNC2 surface. The approach proposed here should yield similar novel developments in gas sensing.