Bulk Heterojunction Photovoltaic Cells with Triphenylamine-Based Amorphous Polymer and Non-Halogenated Solvent Processing Provide Reproducible Performance

The performance of bulk heterojunction (BHJ) organic photovoltaics (OPVs) based on an amorphous polymer, poly(3HTBT-TPA), and fabricated using either halogenated or non-halogenated solvents was investigated. All the BHJ OPVs exhibited almost the same power conversion efficiencies of around 2.2%, indicating that their performance is independent of the casting solvent. These experimental results indicate that the use of amorphous pi-conjugated polymers in the fabrication of BHJ OPVs offers two advantages over the use of polycrystalline pi-conjugated polymers: highly reproducible OPV performance and the possibility of an environmentally friendly process for fabricating OPVs.