Plastic solar panels have attracted a great deal of attention the world over for their promise of supplementing traditional silicon-based solar. The possibility for transparent, flexible and colourful solar panels opens up a host of interesting architectural uses including colourful building facades and tinted windows which can generate electricity while the sun shines. Combine this with the capability of printing these new panels with equipment similar to that used for newspaper printing and you have an exciting, affordable option to help keep up with the world’s rising energy demands.
Processing temperatures for plastic solar
New research from the Flinders Institute for Nanoscale Science & Technology has explored the effect of temperature on some of the plastics which are commonly used in these next generation solar panels. In particular, the team of researchers looked at how changes in the chemical structure of the plastics influence their properties at different temperatures.
Understanding the impact of temperature on the properties of these plastics is important for making sure the new panels will stand up to the high temperatures of an Australian summer, but is also important when deciding the processing temperatures to make the panels in the first place.
The research team, led by Professor Mats Andersson, investigated molecules with a rigid backbone and with side groups coming off this backbone (imagine something a bit like a pipe cleaner). For molecules with a flexible backbone the team found thermal transitions (similar to melting points) originating from both the side chains and the backbone, whereas the molecules with a rigid backbone only had noticeable transitions coming from the side chains. Understanding how temperature influences the physical structure and properties of these molecules is crucial for achieving stable plastic solar panels with the best possible efficiencies.
Safe ingredients for printing panels
Other work in Professor Andersson’s lab has included developing new plastic molecules which can be printed with environmentally friendly solvents. One goal for printable solar panels is to be able to use “roll-to-roll” printing setups, similar to those used in newspaper printing.
“This is done in an open environment,” says researcher Dr. Jonas Mattiasson Bjuggren, “it’s therefore important that we use environmentally friendly components to protect both the environment, and the workers”
The new plastics show promise for use in printed solar panels, with one molecule breaking the efficiency record for an inverted plastic solar cell configuration. The device was lower efficiency when produced using printing techniques, but future research will aim to improve this by optimising the production process.
The work on the effect of temperature on molecules used for plastic solar cells was originally published in the journal Chemistry of Materials. You can read the full paper here.
The research on new molecules which can be printed with environmentally friendly solvents was originally published in the journal Applied Energy Materials. You can read the full paper here.