PbS nanoparticles/polymer composite aggregates through self-assembly of amphiphilic copolymer containing cross-linked hydrophilic block

Poly(methyl methacrylate) macroinitiator and amphiphilic block copolymer poly(methyl methacrylate)-block-poly(lead dimethacrylate) (PMMA-b-PLDMA) were synthesized by two-step sequential atom transfer radical polymerization (ATRP). In this novel amphiphilic block copolymer, the hydrophilic block PLDMA is cross-linked, and the hydrophobic block PMMA is linear. In selective solvent, the copolymers can self-assemble to form crew-cut aggregates comprised of the hydrophobic block PMMA surround by the cross-linked hydrophilic block PLDMA. Through bubbling H2S into the aggregate solution in the next step, PbS nanoparticles can be synthesized in the aggregates in situ. XPS spectra confirm the successful synthesis of the copolymers. AFM, SEM and TEM are used to characterize the morphologies of these composite aggregates.