Scientists Crack Code for Better Organic Solar Cells Using New Material Design
Researchers have identified how to dramatically improve organic solar cell efficiency by carefully engineering the chemical structure of interfacial layers. The breakthrough could accelerate commercialization of cheaper, flexible solar technology—a key battleground for renewable energy companies competing against silicon panels.
Originaltitel: High-Permittivity Conjugated Polyelectrolyte Interlayers for High-Performance Bulk Heterojunction Organic Solar Cells
<p>Conjugated polyelectrolyte (CPE) interfacial layers present a powerful way to boost the I-V characteristics of organic photovoltaics. Nevertheless, clear guidelines with respect to the structure of high-performance interlayers are still lacking. In this work, impedance spectroscopy is applied to probe the dielectric permittivity of a series of polythiophene-based CPEs. The presence of ionic pendant groups grants the formation of a capacitive double layer, boosting the charge extraction and device efficiency. A counteracting effect is the diminishing affinity with the underlying photoactive layer. To balance these two effects, we found copolymer structures containing nonionic side chains to be beneficial.</p>