Abstract : The click‐based microporous organic network (C‐MON) with a thickness of ≈140 nm is introduced to the surface of poly(ethylene terephthalate) (PET) fibers, reinforcing the capture performance of polymer fibers toward PM2.5 . The PET@C‐MON membrane could be recycled after removal of PM2.5 by simple washing. More details can be found in article number1800628 by Chang Wan Kang, Seung Uk Son, and co‐workers.