Selective sequential infiltration synthesis of ZnO in the liquid crystalline phase of silicon-containing rod-coil block copolymers.
Ling-Ying ShiAshwanth SubramanianLin WengSangho LeeKim KisslingerChang-Yong NamCaroline A RossPublished in: Nanoscale (2022)
The combination of block copolymer (BCP) thin film self-assembly and selective infiltration synthesis of inorganic materials into one BCP block provides access to various organic-inorganic hybrids. Here, we apply sequential infiltration synthesis, a vapor-phase hybridization technique, to selectively introduce ZnO into the organic microdomains of silicon-containing rod-coil diblock copolymers and a triblock terpolymer, polydimethylsiloxane (PDMS)- b -poly{2,5-bis[(4-methoxyphenyl)-oxycarbonyl]styrene} (PDMS- b -PMPCS) and PDMS- b -polystyrene- b -PMPCS (PDMS- b -PS- b -PMPCS), in which the PMPCS rod block is a liquid crystalline polymer. The in-plane cylindrical PDMS- b -PMPCS and core-shell cylindrical and hexagonally perforated lamellar PDMS- b -PS- b -PMPCS films were infiltrated with ZnO with high selectivity to the PMPCS. The etching contrast between PDMS, PS and the ZnO-infused PMPCS enables the fabrication of ZnO/SiO x binary composites by plasma etching and reveals the core-shell morphology of the triblock terpolymer.