Morphology-engineered highly active and stable Pd/TiO2 catalysts for CO2 hydrogenation into formate

•Pd/TiO2{100} is highly active and stable for CO2 hydrogenation into formate.•The activity is benefit from the moderate basic site and metallic Pd species.•Higher density of moderate basicity over Pd/TiO2{100} favors for CO2 activation.•More metallic Pd species over Pd/TiO2{100} contributes to H2 activation.•The stability is benefit from strong Pd-TiO2 interactions.•The oxygen vacancy in the TiO2{100} promote the Pd-TiO2 interactions.