Faster Than Light: The Evolution Of Polymer Electrolytes For New Generation Solar Cells In The Last Five Years

The stability of solar cells is a critical (but often disregarded) issue, since great focus is often devoted to the efficiency records (even if these values rapidly decrease upon time). However, today's research in the solar cells field must be connected to concepts such as long-term stability, safety and environmental impact. One of the most studied device is the dye-sensitized solar cell (DSSC), that has recently exceeded 14% efficiency values and is day by day establishing itself as the leading photovoltaic technology in the fields of building-integrated and indoor light-harvesting. In this device, the electrolyte plays a central role in determining both efficiency and durability. Since polymer electrolytes represent the main solution to the issue of poor stability of DSSC devices while maintaining almost intact the power conversion efficiency, the scientific community has recently made great efforts in this direction in recent years. In this work, we present recent approaches in terms of novel polymeric architectures for DSSC polymer electrolytes, introduction of unconventional redox mediators, and photostability increase of solar cells components. Reached the goals of high efficiency and good stability, we show how DSSCs can be used for the fabrication of smart windows in modern buildings. Finally, a few preliminary results about one of the 2016 leading solar cells (i.e., aqueous solar cells) will be given.