Highly Sensitive\nEthylene Glycol Gas Sensor Based\non MIL-68(In)@ZIF‑8 Derivative

Ethylene glycol, as a colorless and\ntasteless organic\ncompound,\nis an important industrial raw material but can be hazardous to the\nenvironment and human health. Thus, the development of high-performance\nsensing materials is required for the monitoring of ethylene glycol.\nIn this paper, a method to synthesize In<sub>2</sub>O<sub>3</sub>@ZnO\nusing MIL-68(In)@ZIF-8 to serve as a sacrificial template is proposed\nfor testing ethylene glycol sensing capabilities. For verifying an\neffective improvement in gas-sensitive performance by bimetallic organic\nskeleton (MOF) synthesized heterojunctions, we performed gas-sensitive\ntests on In<sub>2</sub>O<sub>3</sub>, ZnO, and In<sub>2</sub>O<sub>3</sub>@ZnO. In<sub>2</sub>O<sub>3</sub>@ZnO has the best sensitivity\nto ethylene glycol, including ultrahigh response value (20 ppm-200.12),\nmoderate response/recovery time (53/50 s), and excellent selectivity.\nThe construction of heterojunction is the main reason for enhancing\nthe ethylene glycol response of the sensor. On this basis, the gas-sensitive\nenhancement mechanism of composites is analyzed. The results show\nthat the design method of synthesizing heterojunctions using bis-MOFs\nproposes a new approach that enhances the properties of ethylene glycol.