Inefficient　charge　separation　and　slow　interfacial　reaction　dynamics　significantly　hamper　the　efficiency　of　photocatalytic　CO2　reduction.　Herein,　a　facile　EDC/NHS-assisted　linking　strategy　was　developed　to　enhance　charge　separation　in　heterojunction　photocatalysts.　Using　this　approach,　we　successfully　synthesized　amide-bonded　carbon　quantum　dot-g-C3N4　(CQD-CN)　heterojunction　photocatalysts.　The　formation　of　amide　covalent　bonds　between　CN　and　CQDs　in　the　CN-CQD　facilitates　efficient　carrier　migration,　CO2　adsorption,　and　activation.　Exploiting　these　advantages,　the　CN-CQD　photocatalysts　exhibit　high　selectivity　with　CO　and　CH4　evolution　rates　of　79.2　and　2.7　mu　mol　g(-1)　h(-1),　respectively.　These　rates　are　about　1.7　and　3.6　times　higher　than　those　of　CN@CQD　and　bulk　CN,　respectively.　Importantly,　the　CN-CQD　photocatalysts　demonstrate　exceptional　stability,　even　after　12　h　of　continuous　testing.　The　presence　of　the　COOH*　signal　is　identified　as　a　crucial　intermediate　species　in　the　conversion　of　CO2　to　CO.　This　study　presents　a　covalent　bonding　engineering　strategy　for　developing　high-performance　heterojunction　photocatalysts　for　efficient　solar-driven　reduction　of　CO2.