Functional Noncentrosymmetric Nanoparticle-Nanofiber Hybrids via Selective Fragmentation.

Noncentrosymmetric nanostructures are an attractive synthetic target as they can exhibit complex interparticle interactions useful for numerous applications. However, generating uniform, colloidally stable, noncentrosymmetric nanoparticles with low aspect ratios is a significant challenge using solution self-assembly approaches. Herein, we outline the synthesis of noncentrosymmetric multiblock co-nanofibers by subsequent living crystallization-driven self-assembly of block co-polymers, spatially confined attachment of nanoparticles, and localized nanofiber fragmentation.

Tailored Energy Funneling in Photocatalytic π-Conjugated Polymer Nanofibers for High-Performance Hydrogen Production.

The creation of artificial high-performance photosynthetic assemblies with a tailorable antenna system to deliver absorbed solar energy to a photosynthetic reaction center, thereby mimicking biological photosynthesis, remains a major challenge. We report the construction of recyclable, high-performance photosynthetic nanofibers with a crystalline π-conjugated polyfluorene core as an antenna system that funnels absorbed solar energy to spatially defined sensitized Co(II) porphyrin photocatalysts for the hydrogen evolution reaction. Highly effective energy funneling was achieved by tuning the dimensions of the nanofibers to exploit the very long exciton diffusion lengths (>200 nm) associated with the highly crystalline polyfluorene core formed using the living crystallization-driven self-assembly seeded growth method.

A Smart Phosphine-Diyne Polymer Displays "Turn-On" Emission with a High Selectivity for Gold(I/III) Ions.

A polymeric phosphine sensor is reported that exhibits bright blue fluorescence in the presence of gold(I/III) ions but is nonemissive with other metal ions. Specifically, solutions of a poly(-arylenediethynylene phosphine) copolymer are 35 or 94 times more emissive when treated with solutions of (tht)AuCl or HAuCl·3HO, respectively. Model compound studies confirm phosphine coordination to metals, including gold(I/III) and rhodium(I), and the selective "turn-on" fluorescence was investigated using time-dependent density functional theory calculations.