Surface　engineering　of　covalent　organic　frameworks　(COFs)　represents　a　highly　promising　strategy　for　achieving　superior　capture　capacity　towards　environmental　trace　pollutants.　Herein,　the　three-dimensional　covalent　organic　frameworks　(3D-COFs)　with　tunable　crystallinity　were　synthesized　and　optimized　via　a　simple　solvent　ratio　adjustment,　demonstrating　an　exceptional　capture　capacity　of　polychlorinated　biphenyls　(PCBs).　By　adjusting　the　ratio　of　solvents　(1,4-dioxane　and　toluene),　a　functional　3D　COF　(dia-c5　TPA-TAM-COF)　was　discovered,　providing　an　ideal　approach　to　transform　an　amorphous　compound　into　a　functional　platform　with　a　significant　increase　in　crystallinity,　surface　area　and　pore　volume　for　PCBs　capture.　The　adsorption　features　and　analytical　performance　of　PCBs　were　evaluated,　and　a　good　performance　was　achieved　with　high　enrichment　factors　as　6973　∼　11,015.　Optimization　of　solid　phase　microextraction　(SPME)　using　the　dia-c5　TPA-TAM-COF　as　the　coating　was　investigated,　and　the　method　was　verified　for　sensitive　quantification　of　PCBs　by　using　GC–MS,　achieving　the　sensitive　limits　of　detection　(LODs)　of　0.028　∼　0.0263　ng/L.　Good　reproducibility　and　robustness　of　the　analytical　performance　of　PCBs　using　dis-c5　was　achieved,　with　the　RSDs　of　intra-day　(n　=　3),　inter-day　(n　=　6)　and　fiber-to-fiber　(n　=　3)　of　0.7　∼　4.7　%,　1.8　∼　4.6　%　and　2.0　∼　3.9　%　respectively.　The　recoveries　of　PCBs　in　the　soil　fortified　samples　were　obtained　as　85.3　∼　101.9　%　and　86.3　∼　108.8　%,　respectively,　as　well　as　high　thermal　stability　and　long　lifetime　(keep　on　going　more　than　150　cycles).　This　study　demonstrates　that　a　simple　protocol　of　adjusting　the　solvent　content　was　capable　of　tailoring　high　crystallinity　and　suitable　interpenetration　degree　of　TPA-TAM-COFs　for　high　performance　target　capture　of　PCBs　in　environmental　soils.　©　2025