A　series　of　alkali　metal　silicates　A2SiO3　(A　=　Li,　Na　and　K)　were　synthesized　by　a　sol–gel　method　route　and　employed　as　support　for　Ru　nanoparticles　to　catalyze　NH3　decomposition.　The　NH3　conversion　can　be　ranked　as　the　order　of　Ru/K2SiO3　＞　Ru/Na2SiO3　＞　Ru/Li2SiO3　＞　Ru/SiO2　at　the　same　conditions,　and　Ru/K2SiO3　displays　the　highest　NH3　conversion　of　60.5%　with　the　TOF　H2　of　2.03　s−1　under　the　weight　hourly　space　velocity　(GHSV)　of　30,000　mL.gcat-1.h−1　at　450　oC.　The　combination　results　of　different　characterization　indicate　that　the　formation　of　alkali　metal　silicates　can　increase　the　strength　and　number　of　basic　sites,　and　the　strong　electronic　metal-support　interaction　(EMSI)　would　appear　between　Ru　particles　and　oxygen　vacancies　in　A2SiO3　structure　at　reduction　conditions.　The　presence　of　EMSI　can　result　in　the　higher　Ru　dispersion　and　enhanced　electronic　density　of　Ru　particles　over　A2SiO3,　greatly　facilitating　the　decomposition　of　NH3　to　COx-free　hydrogen.　©　2022　Elsevier　Ltd