The work suggests a way to quickly identify ideal material mixtures and processing methods, bypassing trial-and-error strategies and minimizing labor-intensive synthesis.
To generate electricity from light, the photoactive layer of an organic solar cell (OSC) must allow the photoexcitation and separation of charges, something that can happen in blends of electron-donating and electron-accepting organic materials. Not surprisingly, such blends have been created in steady succession with the goal of improving device efficiency.
However, there are over a thousand combinations of electron donors and acceptors available for use in OSCs and countless processing variations. The reliance on trial and error to identify the best materials and methods is a serious limitation. A way to predict device efficiency based on easily measurable or derivable parameters would go a long way toward streamlining the process.
Image: (extract) Artistic interpretation of an organic solar-cell mixture containing a blend of polymers and fullerenes. Interactions between these molecules (represented by the interaction parameter, χ) affect the degree of mixing that occurs, which in turn is key to device performance.