Modification　of　Ru/CeO2　catalysts　for　ammonia　synthesis　from　H-2　and　N-2　is　of　emerging　interest　for　potential　industrial　application.　Herein,　we　report　an　effective　strategy　by　introduction　silica　to　enhance　ammonia　synthesis　performance　by　tuning　hydrogen　adsorption-desorption　property.　Owing　to　the　enhancement　of　Ru　sites　surrounded　by　oxygen　atoms,　ceria-supported　Ru　catalyst　with　SiO2　adsorbs　more　hydrogen　species,　and　the　desorption　and　exchange　of　hydrogen　species　would　also　be　accelerated.　Therefore,　the　introduction　of　SiO2　into　Ru/CeO2　catalyst　can　improve　the　ammonia　synthesis　activity　by　more　than　34%　at　400　degrees　C,　and　the　catalyst　with　SiO2　shows　a　lower　activation　energy　and　superior　high-pressure　effect　for　ammonia　synthesis.　These　findings　will　open　up　a　new　avenue　for　the　development　of　ammonia　synthesis　and　also　provide　guidance　for　preparing　highly　efficient　oxides-supported　metal　catalysts　in　a　series　of　hydrogen-involving　reactions.　(C)　2022　Elsevier　Ltd.　All　rights　reserved.