CuO/ZnO hollow nanocages derived from metal−organic frameworks for ultra-high and rapid response H2S gas sensor

Rapid and effective hydrogen sulfide ( H 2 S ) detection is vital to ensure safety in industrial environments, where it is a common toxic gas. This study utilized Zn-based metal-organic frameworks (MOFs) as precursors to prepare hollow nanocage structure-like CuO/ZnO sensors. By optimizing the ratio of CuO to ZnO, the resulting CuO/ZnO nanomaterials demonstrated ultra-high sensitivity and a swift response to low H 2 S concentrations. The experimental results show that, thanks to its unique nanocage structure and abundant active sites on the surface, the sensor responds up to 3423 to 10 ppm H 2 S with a response time of only 10 s. In addition, the sensor exhibits good stability, selectivity and low lower detection limit at a low operating temperature of 115 °C, and the lower limit of detection for H 2 S reaches 100 ppb (3.04). Furthermore, the examination of the gas-sensing mechanism exposed the collaboration of CuO/ZnO nanocages in gas adsorption and electron transportation. Remarkably, the generation of p-n heterostructures greatly enhanced the sensitivity and selectivity towards H 2 S , while providing a model for constructing and producing high-performance and enduring sensors.