A whirlwind tour of this evening's MRS poster session

References are to MRS paper numbers. All abstracts can be found at the meeting site.

Two papers from Kyoto University, by Hideo Ohkita et. al. (AA5.32) and Jiamo Guo et. al. (AA5.33), presented good fundamental studies of charge generation and transport in fullerene-polymer bulk heterojunction solar cells. Extra points for providing copies of their posters as takeaways.

In paper KK5.14, Hagay Shpaisman, et. al., take a skeptical look at multiexciton solar cells, questioning whether they offer much improvement over the more conventional, and more tunable, tandem cell.

Yong Soo Kang, et. al. (KK5.1) presents a novel electrolyte for dye-sensitized solar cells, in which hydrogen bonds pull oligomers together in situ to form a self-solidified polymer that can still penetrate the cell's titanium dioxide nanostructure. Someone who saw me taking notes added the caveat that one of the components of the electrolyte is still a liquid; the author wasn't around to answer questions.

I'm not sure I quite understand this one, but in paper AA5.86 Janelle Leger and Glenn Bartholomew propose a single-layer polymer-based p-i-n transistor. The semiconducting polymer incorporates ion transport agents and ion-paired monomers, apparently creating an all-in-one electrochemical cell.

Everyone talks about how nice roll-to-roll fabrication would be, but Daniel Tobjork and coworkers (AA5.45) have actually done it. They used reverse gravure coating to put P3HT:PCBM / PEDOT:PSS organic semiconductor structures on plastic. Results were comparable to those achieved with spin-coating; roll speed controlled the coating thickness.