Unconventional Approach to Fabricating a TiO2 Nanoring with Precise Dimension Control Based on Starlike Polymeric Nanoreactors

The past few years witnessed the rapid development of bottom-up synthesis strategies for preparing various nanostructures (i.e., nanoparticles, nanorods, nanowires, etc.) with distinct morphology-dependent properties. In this study, we reported a facile and efficient synthesis method for preparing anatase titanium dioxide (TiO2) nanorings based on multiarm, starlike amphiphilic polystyrene-b-poly(acrylic acid) (PS-b-PAA) diblock copolymers as nanoreactors which were prepared via a sequential atom-transfer radical polymerization (ATRP) technique followed by the conversion of polystyrene-b-poly(tert-butyl acrylate) (PS-b-PtBA) to PS-b-PAA. The outer PAA block of nanoreactors possessed carboxylic acid groups which could coordinate with a titanium precursor followed by high-temperature calcination to form crystalline TiO2 nanorings. The living nature of ATRP enabled the precise preparation of starlike diblock copolymer nanoreactors with a controlled length of each block (i.e., PtBA and PS), thereby tailoring the inner diameter and wall thickness of the resulting TiO2 nanorings, which were inaccessible to conventional routes.

Automated summary

The study reported a facile and efficient synthesis method for preparing crystalline TiO2 nanorings based on multiarm, starlike amphiphilic polystyrene-b-poly(acrylic acid) diblock copolymers as nanoreactors. The living nature of ATRP enabled the precise preparation of diblock copolymer nanoreactors, allowing tailored control over the resulting TiO2 nanorings' inner diameter and wall thickness that conventional methods cannot achieve.