Synthesizing silica-supported silver nanoparticles at different pHs: Investigating the effect of pH towards dihydrogen yield at high dose-rate using pulse radiolysis

Our work focuses on the synthesis of silica-supported silver nanoparticles in alkaline and acidic media and to investigate the effect of pH towards dihydrogen yield at high-dose rate using pulse radiolysis technique. Supported metal nanoparticles are widely employed in catalysis. The direct application of metal nanoparticles in catalysis is quite inconvenient due to their small size and a high tendency to agglomerate. Thus, metal nanoparticles are deposited on suitable supports such as metal oxides, carbon materials, polymers, mesoporous silica, etc. Since metal-oxides surface compositions depend on pH, it may affect the catalytic reactions pathways. We used 40 nm Stober`s silica nanoparticles (hydrolysis of tetraethyl orthosilicate in ethanol-water mixtures in the presence of ammonia) as the support. The silica nanoparticles were functionalized using bridging molecules to facilitate the attachment of the silver ions. The reduction was carried out using sodium borohydride to form stable alkaline silica supported silver nanoparticles. The obtained supported silver nanoparticles were acidified using various methods until we got stable nanoparticles. The synthesized supported silver nanoparticles were used to study the effect of pH towards dihydrogen yield at high-dose rate using pulse radiolysis technique.