Three　PdZr　bi-component　catalysts　supported　on　modified　silica　have　been　successfully　synthesized　via　different　Zr　introduction　methods　and　utilized　for　the　hydrogenation　of　nitrile　butadiene　rubber　(NBR)　to　produce　high　value-added　hydrogenated　NBR.　It　is　demonstrated　that　the　introduction　of　Zr　can　lead　to　the　formation　of　small-sized　and　electron-rich　Pd　nanoparticles　and　the　order　of　adding　Zr　can　significantly　affect　the　catalytic　activity.　In　particular,　the　PdZr　bi-component　catalyst　obtained　by　introducing　Zr　followed　by　adding　Pd　is　found　to　be　more　stable　on　the　silica　support,　which　exhibits　a　high　hydrogenation　degree　of　90.9%　with　100%　selectivity　to　C[dbnd]C　bond,　close　to　the　single　Pd　catalyst　with　double　Pd　contents.　The　electronic　structure　and　reaction　mechanism　analysis　from　density　functional　theory　calculations　further　reveal　that　the　addition　of　Zr　component　leads　to　negatively　charged　Pd　species　with　lower　energy　barrier　for　the　hydrogenation　of　C[dbnd]C　bond.　Our　findings　provide　a　useful　guidance　for　the　design　of　efficient　and　low-cost　bi-component　catalysts　for　the　selective　hydrogenation　of　unsaturated　polymers.　©　2020　Elsevier　B.V.