Hydrogen explosion suppression is pivotal for the safe utilization of hydrogen energy, necessitating the development of high-performance explosion suppressants tailored for hydrogen explosions. This study presents a strategy to achieve uniform nano-SiO2 encapsulation of KHCO₃ using nano-silica sol as the modification medium, followed by hydrophobic modification to synthesize the eco-friendly KHCO₃@SiO2-F hydrophobic cold aerosol. The effectiveness of KHCO3@SiO2-F for hydrogen explosion suppression was investigated using a 20 L spherical explosion device. The results showed that the KHCO3@SiO2-F hydrophobic cold aerosol could effectively suppress hydrogen explosion. Under stoichiometric H₂-air explosions, the maximum explosion pressure and maximum pressure rise rate decreased by 61.93 % and 83.76 %, and the induction time and the time to peak pressure were significantly extended to 87 ms and 48 ms. The hydrogen suppression mechanism of KHCO3@SiO2-F was revealed through a combined analysis of SEM, FT-IR, XPS and TG-MS characterization results. Particular emphasis was placed on the crucial role of particle size in hydrogen explosion suppression. This study offers novel concepts for the design of hydrogen explosion suppression materials and demonstrates the significant potential of cold aerosol suppressants in explosion suppression.
