Im/BIm ratio–regulated ZIF-62 as a functional filler for high wear–resistant 3D-printed PEEK tribocomposites

The development of high-performance polymer composites—combining strength, low friction, and wear resistance—remains an industrial challenge. In the present study, zeolite imidazolate framework ZIF-62 served as a multifunctional filler to fabricate ZIF-62/PEEK composites via fused deposition modeling (FDM). The effects of ZIF-62 on PEEK’s friction and wear were systematically investigated. By modulating the Im/BIm molar ratio in ZIF-62, we controlled the kinetics and composition of interfacial transfer film formation during sliding, thereby enhancing PEEK’s tribological performance. The optimal composition (ZIF-62/PEEK with Zn:Im:BIm = 1:1.5:0.5) reduced PEEK’s wear rate by 90 % to 1.45 × 10 ⁻⁶ mm 3 /Nm under 4 MPa × 0.25 m/s. The mechanisms behind this improvement were discussed based on multiscale characterization and molecular dynamics simulations. It was revealed that Zn species were released through the breakage of Zn–N bonds and reacted with degraded PEEK to form ZnO, while simultaneously inducing tribo-catalyzed graphitization. These products combined with iron oxides from the counterface to form a robust transfer film. This work establishes ligand engineering as a strategy for designing next-generation PEEK tribomaterials.