Micron rake could double output of polymer solar cells

A joint research project in the US has shown how a new processing tool could significantly increase the electrical performance of polymer-based photovoltaic (PV) materials.

A micron-size rake can improve the morphology of deposited polymer PV films – Source: Stanford University

The work developed a new fluid-enhanced crystal engineering technique dubbed Fluence.

This used a micron-sized rake to smooth out the plastic layers of a solar cell – a process initially developed to boost the conductivity of organic semiconductors.

Stanford
The project begin in October 2011. Researchers at Stanford University Institute for Materials and Energy Sciences (SIMES) cooperated with federal Department of Energy (DoE) National Accelerator Laboratory (SLAC) to optimise the design of the rake.

They found that building a rake with hexagonal pillars 1.5µ high, spaced 1.2 µ apart was most eliminating clumping in deposited PV polymers, to an extent that their electrical performance was doubled. Significant improvements were also noted when the plastics were fed beneath a simple single edge blade, but the rake was still 18% more efficient.