Efficient and Cost Effective Solar Cells: New Materials for Improved Recombination and Charge Dissociation Losses in Organic Photovoltaics
Abstract
Solar energy resources are vast: more energy hits the planet in one hour than humankind
consumes in entire year. However, solar technologies have only been used to a limited degree in
energy production thus far because of high costs.1
Organic solar cells2-21 offer the potential to change
the landscape of how we produce and use energy. If developed into a mature technology, they
present the opportunity to significantly reduce solar energy costs through earth-abundant materials,
efficient installation, and roll-to-roll production.
6-8 Their properties and designs can be tuned and
optimized via materials versatility, solution-based processing, and mechanical flexibility.8-10 In recent
years, there have been numerous improvements in power conversion efficiencies, with the 8%
threshold recently being crossed.22-24 While these efficiencies continue to be notably less than today’s
commercial solar cells, the steady improvement in efficiencies has generated significant interest in
their potential to become practical, widespread sources of energy production. However, in addition to
key lifetime improvement needs, moving to power conversion efficiencies >10% is regarded as an
important threshold for widespread deployment, and therefore, major materials and cell design
advances are still needed. Achieving these developments will require a better understanding of
organic solar cell loss mechanisms before high efficiencies can be achieved.