Researchers from Nanyang Technological University developed ultrathin semi-transparent perovskite solar cells using thermal evaporation
The devices are about 10,000 times thinner than a strand of human hair and achieved efficiencies up to 12% in opaque configurations
The technology is being explored for solar windows, building façades, vehicles, and wearable electronics
Transparent and semi-transparent photovoltaics are becoming an important research area within next-generation perovskite solar cell development. Such technologies are being investigated for integration into architectural glass, vehicles, and consumer electronics.
Researchers from Nanyang Technological University (NTU Singapore) have developed ultrathin semi-transparent perovskite solar cells for applications such as windows, façades, and wearable electronics. The devices were fabricated using a fully vacuum-based thermal evaporation process, which the team says is compatible with large-area manufacturing.
Led by Associate Professor Annalisa Bruno, the group fabricated perovskite solar cells approximately 10,000 times thinner than a strand of human hair. The devices were found to maintain comparatively high power conversion efficiencies even at these reduced dimensions.
The process is based on thermal evaporation, an industrially compatible vacuum deposition technique in which source materials are heated until they evaporate and subsequently condense as thin films on a substrate. According to the study, this approach enables highly uniform perovskite layers over large areas while avoiding toxic solvents commonly associated with solution-based fabrication methods.
By controlling the deposition process, the researchers fabricated perovskite absorber layers as thin as 10 nm. The opaque devices achieved efficiencies of around 7% with 10 nm layers, 11% with 30 nm layers, and 12% with 60 nm layers.
The semi-transparent version, based on a 60 nm perovskite layer, achieved 7.6% efficiency while allowing approximately 41% visible light transmission. The researchers described this as among the best reported performances for semi-transparent perovskite solar cells using similar materials.
“By precisely controlling thermal evaporation, we are able to adjust the transparency of the solar cells. This opens up new possibilities for sustainable architecture, such as tinted windows that generate electricity,” said first author Dr. Luke White, a former PhD student at NTU Singapore.
The team added that the ability of perovskite solar cells to operate under diffuse and indirect light conditions could make them suitable for dense urban environments with limited direct sunlight exposure. The study also suggests that large glass-fronted buildings could produce several hundred megawatt-hours of electricity annually through solar façades.
The researchers stated that this is the first demonstration of ultrathin perovskite solar cells fabricated entirely using vacuum-based processes. The team is now working with industry partners to validate and standardize the process while improving long-term stability and large-area performance.