Four-terminal flexible perovskite-CIGS tandem mini-module with 18.4% effectiveness

• Swiss scientists have actually developed a 4T tandem perovskite/CIGS mini-panel with a geometric fill factor of over 93%. It combines a 10.8%- reliable small perovskite module and a 15.1%- efficient CIGS device.

Researchers from the Federal Laboratories for Materials Science and Technology (EMPA), in Switzerland, have actually demonstrated a four-terminal tandem mini-module based on perovskite and copper, indium, gallium and selenium (CIGS) with an aperture location of around 2 cm2, and a geometric fill element of over 93%.

" The trick to the advancement of reliable flexible perovskite-CIGS thin-film tandem modules is the development of near-infrared (NIR) transparent perovskite solar modules on a flexible polymer foil," the study's equivalent author, Fan Fu, told pv magazine. "Researchers in the Laboratory for Thin Films and Photovoltaics at Empa have actually overcome the difficulties of laser patterning on flexible substratums to recognize the initial all-laser scribed monolithically adjoined NIR-transparent perovskite mini-modules on polymer film."

The perovskite mini-module made use of in the tandem panel was produced on a flexible polyethylene napthalathe (PEN) substrate installed to a glass substrate in a p-- i-- n device design. This arrangement, according to the study team, shows decreased absorption in the NIR area.

The scientists made use of thermally evaporated buckminsterfullerene, a molecule which is also known as C60, for the fabrication of the electron transportation layer (ETL). To shield the underlying layers from ion damages throughout the sputtering of transparent conductive oxide (TCO), they positioned a tin( IV) oxide (SnO2) buffer layer on top of the C60 by atomic layer deposition (ALD). They additionally used P2 scribing to create a pathway to adjoin the surrounding subcells and P3 scribing to isolate the back electrode between the subcells.

The mini-module has a power conversion performance of 10.8% and an average passage of over 75% in the NIR range, that makes it ideal for tandem applications. "The light-harvesting capacity of the NIR-transparent mini-module can be improved by utilizing a thicker wide-bandgap (WBG) perovskite absorber with superb optoelectronic homes," the academics said.

The perovskite module was combined with a CIGS module with an efficiency of 15.1%. "The flexible 4T perovskite-CIGS mini-module performs at an effectiveness of 18.4% and outshines both the perovskite and CIGS stand-alone mini-module," the Swiss group emphasized. "An absolute effectiveness gain of 7.5% and 3.3% is achieved with respect to the perovskite and CIGS stand-alone mini-modules."

The Swiss Scientists provide their findings in "Laser patterned flexible 4T perovskite-CIGS tandem minimodule with over 18% performance," which was recently published in Solar RRL. "The flexible perovskite-CIGS tandem mini-modules can possibly be made use of in applications where versatility and light-weight are essential considerations, such as mobile and wearable electronics, structure- and vehicle-integrated photovoltaics (BIPV and VIPV), internet of things (IoT), and room applications," Fu ended.