Enhanced Selectivity of Hydrogen Sulfide Gas by Hybrid Zeolitic Imidazolate Framework-67/2D Platinum Diselenide-Based...

We developed a novel hybrid gas sensor by integrating zeolitic imidazolate framework-67 (ZIF-67) onto platinum diselenide (PtSe₂) layered thin films, synthesized via a plasma-assisted selenization process. This approach addresses the critical challenge of scalability in 2D material-based sensors. By leveraging the distinct adsorption energies of gas molecules at the metal centers in ZIF-67, the sensors exhibited a significantly enhanced H₂S response of up to 163% at 10 ppm and remarkable selectivity against NH₃, achieving a response ratio (S_H2S/S_NH3) of 10.9. We calculated a theoretical limit of detection (LOD) of 12 ppb, demonstrating suitability for trace-level environmental monitoring. Long-term stability tests over a month demonstrated the superior stability of ZIF-67@PtSe₂ layered films compared to pristine PtSe₂, while maintaining robust performance under high-temperature and high-humidity conditions. Density functional theory (DFT) calculations revealed that ZIF-67 acts as a molecular sieve, selectively capturing H₂S while hindering access to NH₃, elucidating the underlying mechanism for the enhanced selectivity. Crucially, we successfully demonstrated the fabrication of a 4-inch wafer-scale device featuring a highly uniform ZIF-67@PtSe₂ layered thin film that exhibited excellent gas-sensing performance. These results validate the feasibility and potential for large-scale, high-volume manufacturing of ZIF-67@PtSe₂ sensors, bridging the gap between laboratory-scale devices and commercial applications.