Co-Doped ZnO/ZIF-8 Nanorods Arrays for Outstanding Detection Performances Towards Acetone

Developing advanced acetone sensors with exceptional performance is crucial for various applications, including the noninvasive diagnosis of diabetes. In this study, core-shell nanorod arrays (NRs) composed of ZnO and cobalt-doped zeolitic imidazolate framework-8 (ZnO/ZIF-CoZn) were synthesized to achieve high sensitivity and efficiency in acetone detection. Since the synergistic contributions of cobalt-doping and ZIF-8 coatings, the ZnO/ZIF-CoZn-based sensors exhibited high sensitivity and selectivity detection of acetone. The ZnO@ZIF-CoZn sensor showed an enhanced response (9.25) to 50 ppm acetone at 300 °C, which is 5.6 times of ZnO/ZIF-8 sensor. Moreover, the ZnO/ZIF-CoZn exhibited outstanding repeatability, along with enhanced resistance to humidity compared with bare ZnO and ZnO/ZIF-8 NRs. The incorporation of cobalt sites in ZIF-8 has been shown to catalytically activate oxygen, thereby increasing the release of active oxygen onto the surface of ZnO. Simultaneously, the cobalt sites facilitate the dissociation of acetone. Together, these processes influence the catalytic oxidation of gases, ultimately enhancing sensor gas sensing performance. This study integrates the active characteristics of MOFs for gas-sensing process, providing valuable perspectives for expanding the scope of MOF-based catalysis applications.