Surface-nanostructured cactus-like carbon microspheres for efficient photovoltaic devices

A constitutional dynamic chemistry process is developed to synthesize novel cactus-like nanostructured carbon microspheres with high specific surface areas and catalytic activities. Polyazomethine microspheres have been firstly synthesized from two representative monomers of 1,4-terephthalaldehyde and 3,5-diamino-1,2,4-triazole and then carbonized to produce the desired carbon nanomaterials. The morphologies of the surfaces on the carbon microspheres can be controlled with tunable roughness by introducing 2-aminopyridine. As an application demonstration, these nanostructured carbon microspheres are used as counter electrodes to fabricate efficient dye-sensitized solar cells with energy conversion efficiencies up to 7.5%.