Preparation of Pd/PdO@ZnO-ZnO nanorods by using metal organic framework templated catalysts for selective detection of triethylamine

Abstract Sensors based on Pd/PdO@ZnO-ZnO nanorods (NRs) were fabricated for selective detection of triethylamine (TEA). ZnO NRs were obtained by simple hydrothermal method. The Pd/PdO functionalization was sensitized on ZnO NRs by using metal-organic framework (MOF) templated catalysts (Pd@ZIF-8). Eventually, Pd supported on ZnO nanocubes was about 3 nm and PdO nanoparticles with ~10 nm were loaded on the surface of the ZnO NRs. Gas sensing properties showed that the Pd/PdO@ZnO-ZnO NRs exhibited enhanced response to TEA at 275 ℃ (Rair/RTEA = 258–50 ppm), which was 12.3 folds that of pure ZnO NRs. In addition, the detection limit and working temperature of the sensor were also improved. Importantly, sensors based on Pd/PdO@ZnO-ZnO NRs showed better TEA sensing performance compared to Pd/PdO functionalized samples by the traditional impregnation method. These results could be mainly due to the modulation of sensor base resistance and the catalytic and the spillover effect of PdO and the ultra-small Pd. This work confirms that MOF templated catalyst loading for high performance gas sensors is an effective route to realize the detection of triethylamine gas.