Exfoliated conjugated porous polymer nanosheets for highly efficient photocatalytic hydrogen evolution

In this contribution, we developed a simple, scalable, and universal strategy to exfoliate conjugated porous polymers (CPPs) into 2D nanosheets. A series of pyrenyl (Py)-, benzene (B)-, thienyl (T)-, thieno[3,2-b]thiophene (Tt)- and dithieno[3,2-b:2 ',3 '-d]thiophene (Ttt)-based CPPs were facilely exfoliated into 2D ultrathin sheets with a thickness of 5-18 nm in reasonable yields of 6-20% upon sonication in N-methyl pyrrolidone. Owing to more exposed active sites and shorter migration distances of charge carriers, the photocatalytic hydrogen production rate of the CPP 2-D nanosheets is 1.5-20 times higher than those of their bulk counterparts. The current study represents the first systematic report on the solvent-assisted exfoliation of CPP materials to produce 2D ultrathin lamellae from bulk CPPs with common structures, which might provide new possibilities for the practical application of 2D CPPs.