Effect of PdO-PdO2 core-shell nanocatalysts on hydrogen sensing performances of flame-made spinel Zn2SnO4 nanoparticles

In this research, flame-spray-made Pd-loaded Zn2SnO4 nanoparticles with 0.1-2 wt% Pd contents were synthesized and thoroughly investigated for hydrogen (H-2) sensing. The flame-made nanoparticles were formed into sensing films via spin coating and tested towards H-2 over the concentration ranging from 300 10000 ppm at varying working temperatures of 200-350 ?& nbsp;in dry air. X-ray analysis, nitrogen adsorption, and electron microscopic results revealed that Pd-loaded Zn2SnO4 nanostructures consisted mainly of 5-15 nm round and polygonal Zn2SnO4 nanoparticles uniformly decorated with 1-2 nm PdO-PdO2 core-shell nanoparticles. According to gas-sensing test data, the 1 wt% Pd-loaded Zn2SnO4 sensing film exhibited the greatest sensor response of ~ 5612 to 10000 ppm H-2 at 300?, which was more than three orders of magnitude higher than that of unloaded one. In addition, Pd-loaded Zn2SnO4 nanoparticles display moderately low humidity sensitivity and high H-2 selectivity against C8H10, C7H8, C6H6, CH4, HCHO, CH3OH, C2H5OH, C3H6O, CH2O2, C2H4O2, C3H6O2, C4H8O2, C5H10O2 and C3H6O3. Therefore, the 1 wt% Pd-loaded Zn2SnO4 sensor is highly promising for selective and sensitive H-2 detections in practical applications.

Automated summary

Pd-loaded Zn2SnO4 nanoparticles synthesized by flame spray can be used for hydrogen sensing with high selectivity and sensitivity.