Artificial　photoreduction　of　CO2　to　chemical　fuel　is　an　intriguing　and　reliable　strategy　to　tackle　the　issues　of　energy　crisis　and　climate　change　simultaneously.　In　the　present　study,　we　rationally　constructed　a　Ni　(OH)(2)-modified　covalent　triazine-based　framework　(CTF-1)　composites　to　serve　as　cocatalyst　ensemble　for　superior　photoreduction　of　CO2.　In　particular,　the　optimal　Ni(OH)(2)-CTF-1　composites　(loading　ratio　at　0.5　wt%)　exhibited　superior　photocatalytic　activity,　which　surpassed　the　bare　CTF-1　by　33　times　when　irradiated　by　visible　light.　The　mechanism　for　the　enhancement　was　systematically　investigated　based　on　various　instrumental　analyses.　The　origin　of　the　superior　activity　was　attributable　to　the　enhanced　CO2　capture,　more　robust　visible-light　response,　and　improved　charge　carrier　separation/transfer.　This　study　offers　an　innovative　pathway　for　the　fabrication　of　noble-metal-free　cocatalysts　on　CTF　semiconductors　and　deepens　the　understanding　of　photocatalytic　CO2　reduction.　(C)　2021　Elsevier　Inc.　All　rights　reserved.