Metal-organic frameworks-derived porous ZnO/Ni0.9Zn0.1O double-shelled nanocages as gas sensing material for selective detection of xylene

- ZnO/Ni0.9Zn0.1O double-shelled nanocages were prepared via a metal-organic framework route.
- The strategy includes the synthesis of ZIF-8/Ni-Zn hydroxides and ZnO/Ni0.9Zn0.1O DSNCs.
- The ZnO/Ni0.9Zn0.1O DSNCs shows excellent sensing performance to xylene.

The utilization of metal-organic frameworks (MOFs) as precursors or templates to design synthesize nanostructured metal oxides has attracted intense interest for their great potential applications in gas separation/storage, drug delivery, catalysis device, gas sensors, etc. In this paper, porous double-shelled nanocages (NCs), namely ZnO/Ni0.9Zn0.1O double-shelled nanocages (DSNCs), were synthesized simply through a metal-organic frameworks (MOFs) route. The ZIF-8 rhombododecahedron was first synthesized and then transformed into ZIF-8/Ni-Zn layered double hydroxides (LDH) precursor. Finally, the ZnO-inner/Ni0.9Zn0.1O-outer DSNCs were obtained through thermal annealing of the as-prepared precursor in air. The ZnO/Ni0.9Zn0.1O DSNCs, when utilized as gas sensing material, exhibited high sensitivity and selectivity towards xylene. Besides, enhanced gas sensing properties of ZnO/Ni0.9Zn0.1O DSNCs were observed when compared with ZnO NCs. Such outstanding gas sensing performance of the ZnO/Ni0.9Zn0.1O DSNCs benefits from their high porosity, large specific surface area, and synergistic effect of ZnO and Ni0.9Zn0.1O.