NSF-funded engineers have developed a way to build more efficient solar cells with polymer materials in an environmentally friendly process.
The use of plastic materials can lead to more robust, flexible and cheaper solar cells, which could lead to more widespread adoption of solar energy as a sustainable energy resource. Introducing a process free of toxic liquid solvents minimizes the environmental impact of solar cell manufacturing.
A dye-sensitized solar cell uses a photosensitizer dye to absorb sunlight and convert solar energy into more practical electrical energy. It uses a liquid electrolyte to conduct charges within the cell. However, the liquid electrolyte is prone to leaking and severely limits how the cell can be deployed. Replacing it with a solid polymer electrolyte that can perform the same function as the liquid electrolyte is a significant step forward. The solid polymer can completely fill the nanoscale pore spaces of the solar cell construct, meaning greater cell efficiency.
One hitch: Polymer-built solar cells are constructed using a "wet" method that interferes with the cell. But Kenneth Lau of Drexel University and his research team developed an efficient technique for making polymer cells that eliminates use of toxic liquids. Thus the wettability issues are eliminated and the process is more environmentally friendly.
Cells made using this processing technology have shown higher efficiencies. The results of this research were published in the journal Nano Letters.