Spatial Control over Brush Growth through Sunlight‐Induced Atom Transfer Radical Polymerization Using Dye‐Sensitized TiO2 as a Photocatalyst

Simulated‐sunlight induced atom transfer radical polymerization is used for spatial control over polymer brush growth by in situ photo‐generation of the Cu^I/L activator complex from its higher oxidation state Cu^II/L deactivator complex using dye sensitized titanium dioxide nano­particles. The polymerization is well controlled under sunlight irradiation. Another attractive feature of this method is the possibility of creating various patterned surfaces of brushes using photomasks. When a nanoporous alumina oxide membrane is used as the template for confinement diffusion of photogenerated Cu^I/L catalyst, patterns with sub‐50 nm resolution are obtained.