Facile Synthesis and Optimization of High-Performance H2S Gas Sensors Based on Pt-Co3O4@ZnO Nanofibers With Dual-MOF Structure

Metal-organic framework (MOF) materials are recognized as outstanding templates for preparing porous metal oxides used as gas-sensitive materials. Here, a facile synthesis strategy is proposed to prepare Pt-Co₃O₄@ZnO hollow porous nanofibers with MOF-on-MOF structure and noble metal for gas-sensing applications. Sensors fabricated with this unique nanomaterial show fast response, low detection limit (LOD), high selectivity, and good stability to H₂S gas. Notably, the gas response of the sensor with Pt-Co₃O₄/ZnO nanofibers is three times that for the sensor with Co₃O₄/ZnO, and the optimal operating temperature is reduced by $125~^{\circ }$ C. Furthermore, the gas-sensing mechanism is proposed in detail, and theoretical calculations based on the first principles further reveal the performance enhancement of Pt-Co₃O₄/ZnO nanofibers to H₂S. This study offers a strategy for fabricating noble metal-dropping dual MOFs-based nanofibers with abundant pores and high surface area for high-performance gas-sensing applications.