The Perovskite-Info newsletter (March 28, 2023)

Researchers from the Chinese Academy of Science (CAS) have examined the space-resolved photoluminescence and lasing behaviors of single crystal (SC) and polycrystalline (PC) perovskites upon femtosecond laser ablation. 

They discovered that femtosecond laser ablation had a considerable influence on the space-resolved photoluminescence (PL) and lasing behavior of both single crystal and polycrystalline MAPbBr₃ perovskites. Due to their distinct defect chemistries and morphologic profiles, the femtosecond laser-generated regions of the material were discovered to have different light emitting behaviors in comparison to the unaffected surface area.

Researchers at Shaanxi Normal University in China have developed an organic-inorganic hybrid perovskite solar cell that uses 2D perovskite crystal as the template for 3D perovskite growth. In the recent study, the team developed a seed-mediated method to in situ grow a layer of 2D perovskite seed for epitaxial growth of 3D perovskite atop it, to construct a high-quality 2D/3D heterojunction. 

It was reportedly found that the epitaxial 3D perovskite film exhibited a preferred direction, which is different from traditional perovskites with a preferred orientation. The oriented perovskite film consists of large-sized grains with low defect density, long charge-carrier lifetime and good stability, resulting in efficient PSCs with a champion efficiency of 24.83%. 

Researchers at the National Renewable Energy Laboratory (NREL), City University of Hong Kong, École Polytechnique Fédérale de Lausanne (EPFL), University of Kentucky, University of Colorado, University of Toledo and Brown University have developed a concept  that simplifies the process of manufacturing perovskite solar cells, which could accelerate their path toward commercialization.

Perovskite solar cells are made by sequentially depositing various layers onto a conductive glass substrate, requiring multiple coatings to create the necessary full device structure. The new technique eliminates or combines some of those steps, thereby simplifying the manufacturing process, which could lead to lower manufacturing costs.

Researchers at University of Rome “Tor Vergata”'s CHOSE (Centre for Hybrid and Organic Solar Energy) and CNR-ISM Institute of Structure of Matter have deposited flexible perovskite solar modules without using toxic solvents, via blade coating in ambient air. 14% PCE was reportedly obtained through the optimization of coating parameters and the use of additives. 

The scalable ambient air deposition of perovskite solar devices remains a major challenge of this technology. In addition, toxic solvents are regularly used in perovskite layer deposition, which can damage the environment and endanger the safety of potential production lines. In this recent work, the team managed to address these issues and fabricate sustainable flexible perovskite solar modules (flex-PSMs), in which all layers were deposited via a blade coating in ambient air without the usage of toxic solvents.