Tunable Polymer Nanoreactors from RAFT Polymerization-Induced Self-Assembly: Fabrication of Nanostructured Carbon-Coated Anatase as Battery Anode Materials with Variable Morphology and Porosity
Yen Theng Cheng, Qingbo Xia, Hongwei Liu, Marcello B. Solomon, Emma R. L. Brisson, Lewis D. Blackman, Chris D. Ling, Markus Müllner
Abstract
We demonstrate a modular synthesis approach to yield mesoporous carbon-coated anatase (denoted as TiO 2 /C) nanostructures. Combining polymerization-induced self-assembly (PISA) and reversible addition–fragmentation chain-transfer (RAFT) dispersion polymerization enabled the fabrication of uniform core–shell polymeric nanoreactors with tunable morphologies. The nanoreactors comprised of a poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) shell and a poly(benzyl methacrylate) (PBzMA) core. We selected worm-like and vesicular morphologies to guide the nanostructuring of a TiO 2 precursor, namely, titanium(IV) bis (ammonium lactato)dihydroxide (TALH). Subsequent carbonization yielded nanocrystalline anatase and simultaneously introduced a porous carbon framework, which also suppressed the crystal growth (∼5 nm crystallites). The as-prepared TiO 2 /C materials comprised of a porous structure, with large specific surface areas (>85 m 2 /g) and various carbon contents (20–30 wt %). As anode components in lithium-ion batteries, our TiO 2 /C nanomaterials improved the cycling stability, facilitated high overall capacities, and minimized the capacity loss compared to both their sans carbon and commercial anatase analogues.