Development of Efficient Organic Photovoltaics using Green Solvent-Based Processing

The development of environmentally friendly and sustainable energy source became important in future generation and also a resolution for the climate change issue. Recently, organic photovoltaics (OPVs) have gained much attention due to the possible low-cost fabrication, good flexibility, lightweight, and transparency that can provide various applications such as windows PV, building integrated PV (BIPV), indoor power source, or façade PV, different from silicon-based PVs. However, typically used processing media for the fabrication of OPVs is yet highly toxic halogenated solvents and small amount of harmful processing additives.<br/><br/>In this study, efficient OPV based on using green solvent media was developed which showed a power conversion efficiency (PCE) of 7-8% without using traditional chlorinated solvents such as chlorobenzene. The use of alternative non-halogenated solvent combined with a new non-toxic, non-halogenated processing additive was also investigated and demonstrated comparable or even higher PCEs compared to typical 1,8-diiodooctane (DIO) solvent processing additive. The result shows potential possibility for fully green fabrication of highly efficient next generation OPVs.