MOF-Derived In₂O₃/BiVO₄ Composites for Sensitive and Trace Detection of <i>n</i>-C₄H₉OH

MOF-derived MOS with mesoporous structures and large surface areas are regarded as ideal materials for fabricating high-performance gas sensors. In this study, we successfully synthesized MOF-derived In₂O₃/BiVO₄ composites through a three-step method that includes solvothermal, hydrothermal, and mechanical stirring processes. The characterization results indicate that the In₂O₃/BiVO₄ composites exhibit both hollow microtube and fishbone-like structures. Notably, under 200 °C, the response of the In₂O₃/BiVO₄-2-based sensor to 100 ppm <i>n</i>-C₄H₉OH gas reaches as high as 149.2, which is 7.8-fold greater than that of pure In₂O₃. In addition, the In₂O₃/BiVO₄-2 sensor demonstrates an ultralow theoretical detection threshold (12.6 ppb), satisfactory reproducibility, and remarkable selectivity to <i>n</i>-C₄H₉OH. By integrating experimental results with first-principles calculations, we elucidate the underlying mechanisms that enable In₂O₃/BiVO₄ composites to exhibit remarkable responsiveness and exceptional selectivity toward <i>n</i>-C₄H₉OH gas. This research presents an innovative approach for creating high-performance <i>n</i>-C₄H₉OH gas-sensing materials.