His starting material, as he describes in a paper in Nature Nanotechnology, is made of closely packed polystyrene spheres about a millionth of a metre in diameter.

This paper reports the study on the sulfonated polystyrene resin used in esterification, transesterification, synthesis of acetals or ketals, synthesis of ether and rearrangement reaction of pinacol.

Evaporation self-assembly method, which is used to assemble sub-micrometer polystyrene microspheres, is presented in this paper.