Scientists in the US, Mexico and China have developed semi-transparent organic photovoltaic (OPV) cells with high performance, tuneable transparency and excellent colour perception and rendering properties.
The performance of semi-transparent OPV devices is much lower than their opaque counterparts, and much needs to be done to study and optimise their properties. The team has made semi-transparent OPVs using a low bandgap polymer. By tuning the thickness of the reflective metal electrode, they achieve power conversion efficiencies of 4.25–7.56% and transparency from 2–36%.
They say that their cells have significantly improved performance compared to other semi-transparent OPVs with similar transparencies. The colour rendering indices (CRIs)* of their devices are close to 100, the best values ever reported. (* CRI = quantitative measure of the ability of a light source to reproduce the colours of various objects faithfully in comparison with an ideal or natural light source.)
Polymer solar cells are of interest due to their roll-to-roll fabrication and associated low cost. Semi-transparent OPV devices are a promising candidate for power-generating window applications, as they can be integrated with conventional elements in buildings and vehicles.
Read the ‘HOT’ EES article:
Semi-transparent polymer solar cells with 6% PCE, 25% average visible transmittance and color rendering index close to 100 for power generating window applications
Kung-Shih Chen, Jose Francisco Salinas, Hin-Lap Yip, Jianhui Hou and A Jen
Energy Environ. Sci., 2012, DOI: 10.1039/C2EE22623E