Photocatalytic　reduction　of　CO2into　available　organic　compounds　has　received　remarkable　attention.　However,　photocatalytic　CO2reduction　is　limited　to　meet　industrial　application　requirements　because　of　the　lack　of　effective　photocatalysts.　Surface　frustrated　Lewis　pairs　(FLP)　are　found　in　bismuth　oxybromide　(BiOBr),　which　are　effective　catalytic　sites　to　activate　and　photocatalytically　reduce　CO2.　Furthermore,　the　introduction　of　Ce4+and　oxygen　vacancy　can　optimize　both　the　electronic　state　and　the　FLP　property　of　BiOBr.　The　combined　experimental　and　theoretical　characterizations　reveal　that　Ce4+and　O2-can　form　the　frustrated　Lewis　acid-base　pairs,　which　can　catch,　excite,　and　reduce　CO2into　CO　at　a　high　yield　of　50.9　μL　h-1,　being　9.8　times　as　large　as　pristine　BiOBr.　This　work　illustrates　a　rational　strategy　for　both　construction　of　highly　efficient　photocatalysts　and　insights　into　the　photocatalytic　mechanism　at　the　atomic　level.　©　2022　American　Chemical　Society.　All　rights　reserved.