Toward transparent and colorless Dye-Sensitized Solar Cells for non-intrusive BIPV

Non-intrusive photovoltaic panels could represent the next frontier in the integration of PV technology in transparent windows (i.e. for residential buildings, automotive applications, greenhouses). Among the different PV technologies, Dye-Sensitized Solar Cells (DSSC) offer a unique sustainable choice for transparent and even colorless windows, thanks to their wide versatility in the choice of dyes, electrolytes and redox couples as well as their ability to use diffuse light and work in low-light conditions. The photosensitizer plays a crucial role in obtaining transparent wavelength-selective NIR-DSSC system. [1] Until now, different families of NIR chromophores have been investigated with relatively low success in terms of transparency and power conversion efficiency. Recently, thanks to the joint efforts of different research groups within the IMPRESSIVE project (https://impressive-h2020.eu/), we proposed a fully transparent and colorless DSSC that can display 3.1% power conversion efficiency, up to 76% average visible transmittance (AVT), while reaching a color rendering index (CRI) of 92. [2] Starting from this result, innovative strategies on synthesis approach and cell optimization should be applied to outperform the obtained values and design stable and low-cost compatible materials able to be implemented in a real device.