Hierarchically Structured Nanotube Arrays as Heterogenous Photocatalysts for Highly Efficient Broadband Photoinduced Controlled Radical Polymerization

Highly ordered TiO2 nanotube arrays (TNTAs)and theirheterostructure nanocomposites by structural engineering design wereutilized as heterogeneous photocatalysts for highly efficient broadbandphotoinduced controlled radical polymerization (photoCRP), includingphotoATRP and PET-RAFT. Highly efficient broadband UV-visiblelight responsive photoCRP was achieved by combining the accelerationeffects of electron transfer derived from the distinctive highly orderednanotube structure of TNTAs and the localized surface plasmon resonance(LSPR) effect combined with the formation of the Schottky barriervia modification of Au nanoparticles. This polymerization system wascapable to polymerize acrylate and methacrylate monomers with highconversion, living chain-ends, tightly regulated molecularweights, and outstanding temporal control properties. The heterogeneousnature of the photocatalysts enabled simple separation and effectivereusability in subsequent polymerizations. These results highlightthe modular design of highly efficient catalysts to optimize the controlledradical polymerization process.

Automated summary

Highly ordered TiO2 nanotube arrays (TNTAs) and their heterostructure nanocomposites were used as photocatalysts for efficient broadband photoinduced controlled radical polymerization (photoCRP). The combination of electron transfer acceleration from TNTAs' structure and the localized surface plasmon resonance (LSPR) effect with the formation of Schottky barrier via Au nanoparticle modification enabled efficient UV-visible light responsive photoCRP. The resulting polymers exhibited high conversion, living chain-ends, tightly regulated molecular weights, and excellent temporal control properties.