Large-scale ordering of nanoparticles using viscoelastic shear processing

Abstract

We report on a way to make and transfer large-area (100 cm 2) free-standing 2D or 3D colloidal photonic crystal (CPC) films deposited using a roll-to-roll Langmuir-Blodgett technique from silica or polymer particles. Using this approach, a 'sticker' composed of a monolayer array of silica particles with 120 nm diameter in polyvinyl alcohol (PVA) glue was transferred onto a commercial flexible organic photovoltaic cell improving its conversion efficiency by some 5.2-8.3% at off-normal 0°-45° angles. The results presented here open up a range of new options for application of CPC films in the areas of photovoltaics and light-emitting devices.