High Performance H<sub>2</sub>S Sensor Based on Ordered Fe<sub>2</sub>O<sub>3</sub>/Ti<sub>3</sub>C<sub>2</sub> Nanostructure at Room Temperature
Changkun Qiu, Hao Zhang, Qingrun Li, Yifan Song, Fei An, Haozhi Wang, Shiqiang Wang, Liang Zhu, Dongzhi Zhang, Zhe Yang
Abstract
The utilization of a heterogeneous nanojunction design has shown significant enhancements in the gas sensing capabilities of traditional metal oxide gas sensors. In this study, a novel room temperature H 2 S gas sensor employing Fe 2 O 3 functionalized Ti 3 C 2 MXene as the sensing material has been developed. This sensor exhibits a broad detection range (0.01–500 ppm), low detection limit (10 ppb), and rapid response/recovery times (10 s/15 s), making it ideal for ppb-level H 2 S detection. The exceptional gas sensitivity of Fe 2 O 3 /Ti 3 C 2 composite to H 2 S can be attributed to several key factors. First, the unique layered frame structure of Fe 2 O 3 /Ti 3 C 2 significantly amplifies the surface area of the hybrid material, enhancing the absorption and diffusion capabilities of H 2 S molecules. Second, the abundance of functional groups (–O, –OH, and –F) on the surface of Ti 3 C 2 MXene nanosheets provides additional active sites for H 2 S adsorption, The density functional theory calculation confirms that the adsorption energy of the Fe 2 O 3 /Ti 3 C 2 composite for H 2 S (−2.93 eV) is significantly lower than that of pure Fe 2 O 3 (−2.37 eV) and Ti 3 C 2 (−0.2 eV). Lastly, the remarkable metal conductivity of Ti 3 C 2 MXene ensures efficient electron transfer, thereby enhancing overall sensing performance.