CENIMAT, a partner of APOLO project, published this Februrary an article in Nano Energy Journal, a scientific journal about nanomaterials and nanodevices used in all forms of energy harvesting, conversion, storage, utilization and policy. from ELSEVIER. The article is about photonic-structured Titanium Dioxide (TiO2) perovskite solar cells and its advantages. The most relevant result is that this optically lossless material (TiO2) allowed to create solar cells with optical improvements and not electrical deterioration, something difficult to reach before. CENIMAT is the Materials Investigation Centre of the New University of Lisboa, and it is involved in this project since its beginning in April 2018.
Optical solutions are promising for Perovskite solar cell (PSC) technology, not only to increase efficiency, but also to allow thinner absorber layers (higher flexibility) and improve stability. This work optimized the combined anti-reflection and scattering properties of two types of light trapping (LT) structures, based on TiO2 semi-spheroidal geometries with honeycomb periodicity, for application in PSCs with substrate configuration and different perovskite layer thicknesses. Their optically lossless material (TiO2) allows the structures to be patterned in the final processing steps, integrated in the cells’ top n contact, therefore not increasing the surface area of the PV layers and not degrading the electric performance via recombination. Therefore, this strategy circumvents the typical compromise of state-of-the-art LT approaches between optical improvements and electrical deterioration, which is particularly relevant for PSCs since their main recombination is caused by surface defects. When patterned on the cells’ front, the wave-optical micro-features composing the LT structures yield up to 21% and 27% photocurrent enhancement in PSCs with conventional (500 nm thick) and ultra-thin (250 nm) perovskite layers, respectively; which are improvements close to those predicted by theoretical Lambertian limits. In addition, such features are shown to provide an important encapsulation role, preventing the cells’ degradation from UV penetration.
Click on the following link to read the full article: www.sciencedirect.com