Pt sensitized ZnO microsphere for enhanced hydrogen sensing

Hydrogenation reaction is a highly dangerous yet widely applied chemical process. Monitoring hydrogen leakage during this reaction is essential to ensure industrial safety. To address this need, a highly sensitive hydrogen sensor has been developed based on Pt sensitized ZnO microsphere as sensing materials, which was prepared by annealing-assisted one-pot solvothermal method. Compared with the previously reported work, this strategy enables the controlled synthesis of uniform and monodisperse ZnO microspheres, ensuring highly controllable and reproducible precious metal loading, which is conducive to large-scale production. Thanks to higher oxygen vacancy concentrations, enhanced mesopore volume fractions, and a larger specific surface area, the 1 at% Pt-ZnO sensor at an annealing temperature of 500 °C demonstrates excellent hydrogen detection performance, including a higher response value (1,480,000), a lower detection limit (100 ppb), outstanding selectivity (response to interfering gases <1%), and good short-term repeatability (relative standard deviation of 6.98% over 8 cycles). Furthermore, the sensor has also been applied in the hydrogenation process of 2,4-dinitrotoluene for hydrogen leak monitoring, effectively detecting hydrogen leaks at concentrations of 30-40 ppm, confirming its potential for leak detection in typical hydrogenation reaction.