Crystal　defects　widely　exist　in　semiconductor　photocatalysts,　and　it　hinders　the　quantum　efficiency　in　photocatalytic　reactions.　The　precise　manipulation　and　elimination　of　these　detrimental　defects　are　particularly　crucial　for　improving　the　photocatalytic　overall　water　splitting　(OWS)　reaction,　though　this　remains　a　considerable　challenge.　In　a　recent　study,　Wang　and　colleagues　introduced　an　innovative　＂in-situ　salt　flux＂　copolymerization　technique　to　synthesize　poly(triazine　imide)　(PTI)　with　high　crystallinity　and　minimal　defects.　This　approach　resulted　in　a　record　apparent　quantum　efficiency　(AQE)　of　37.8%　at　380　nm.　This　strategy　effectively　balances　the　impact　of　two　types　of　vacancies　(carbon　and　nitrogen)　on　OWS　performance　and　establishes　clear　structure-property-activity　relationships　for　the　photocatalytic　OWS　process.