One‐dimensional hollow porous Ru–CuO nanofibers covered with ZIF‐71 for H 2 S gas sensing and its first‐principle study

Abstract Based on the unique catalytic properties of precious metals, the introduction of precious metals into metal oxide semiconductors will greatly improve the gas‐sensitive properties of materials. As a new type of porous material, metal–organic frameworks (MOF) can be used for gas separation and adsorption due to their adjustable pore size and acceptable thermal stability. In this work, the ZIF‐71 MOF was synthesized on CuO nanofibers doped with different concentrations of Ru to form a Ru–CuO@ZIF‐71 nanocomposite sensor, which was then used for H 2 S detection. The sensor shows sensitivity to trace amounts of H 2 S gas (100 ppb), and the response is greatly enhanced at the optimal Ru doping ratio and operating temperature. The introduction of the ZIF‐71 membrane can significantly increase the selectivity of the sensor while further improving the sensitivity. Finally, the possible sensing mechanism of the Ru–CuO@ZIF‐71 sensor was explored. The enhancement of the H 2 S gas sensing properties may be attributed to the catalysis of Ru and the formation of the Schottky junction at the Ru–CuO interface. Besides, the calculation based on density functional theory reveals enhanced adsorption capacities of CuO for H 2 S after Ru doping. Therefore, the Ru–CuO@ZIF‐71 sensor has strong application potential in exhaled gas detection and portable detection of H 2 S gas in industrial environments.