星期四, 九月 24, 2020
Home PV News Trimming optical losses in tandem perovskite cells

Trimming optical losses in tandem perovskite cells

Spanish researchers have unveiled a monolithic nano-structured perovskite silicon tandem device they claim can reduce optical losses by more than a third compared to planar perovskite cells of the same kind.

Source:Pv magazine

Researchers at Spain’s Charles III University of Madrid claim to have significantly reduced optical losses in a monolithic, nano-structured perovskite silicon tandem solar cell by using a new design.

Such two-terminal tandem cell devices are said to offer high conversion efficiency, due to a large number of layers, but to also suffer significant optical losses because of the high number of interfaces.

“Our proposed design increases the performance of both sub-cells by managing light towards the active layer, as well as by minimizing reflection losses in the interfaces,” the scientists wrote in the paper A monolithic nanostructured-perovskite/silicon tandem solar cell: feasibility of light management through geometry and materials selection, published in Nature.

Current-matching

The Madrid team said current-matching between the sub-cells was crucial to reducing optical losses, and in particular reflection losses, which would otherwise be exhibited during the extraction of photo-generated charges.

“The simplified design of the solar cell comprises the following layers from bottom to top: silver contact (300nm)/crystalline silicon (c-Si, 200µm)/indium tin oxide (ITO, 44nm) and a nano-structure sandwiched between the electron transport layer (ETL) and the hole transport layer (HTL) with a width regulated by a dielectric spacer (DS),” the paper noted.

For the simulation, the researchers used the methylammonium lead iodide (MAPbI3) perovskite, one of the most commonly applied in solar energy research, to fill the gaps between the numerous cell layers. The analysis – which is said to have explored the geometrical dimensions and materials for the electron transport layer, the hole transport layer and the dielectric spacer – meant the researchers could discover the value ranges of refractive indices which could enable the minimization of optical losses.

Difficulty

The Madrid team admitted their cell architecture may be particularly difficult to scale up to mass production but pointed out, according to the literature it would not be unfeasible, as more complex structures of a similar kind have been fabricated.

“We obtain a reduction in the optical losses, in particular they are more than 33% lower than those of a planar cell, mainly due to a reduction of the reflectivity in the device,” the scientists wrote. “An evident reduction of the losses using the nano-structure appears, achieving almost a reduction of 50% in the best case.”

The Spanish team claim to have also demonstrated a wide range of dimensions of the layers which could allow current-matching between them while maintaining good optical performance.

In July 2018, Belgian research institute Imec announced it had achieved 27.1% efficiency in a perovskite/silicon tandem cell by reducing interconnection losses.

LEAVE A REPLY

Please enter your comment!
Please enter your name here

- Advertisment -

Most Popular

Apple data center in Denmark powered by 50 MW of solar

Apple has revealed that its data center in Viborg, Denmark, is now being powered by a 50 MW solar project under a long-term power...

Solar + storage experiment in Tampa Bay selected for Solar Energy Innovation Network project

An innovative solar + storage research project led by the Tampa Bay Regional Planning Council has been selected as a finalist for the Solar...

Chinese PV Industry Brief: 350 MW wind-solar project, 200 MW of floating PV

Longyuan Energy said this week that it has signed an agreement with the municipal authorities in Binzhou, Shandong province, to build 300 MW of solar...

IEEE creates education and credentialing program for interconnecting distributed resources to the grid

IEEE and the IEEE Standards Association (IEEE SA) announced the IEEE Std 1547-2018 Distributed Energy Resources (DER) Interconnection Commissioning: Education and Credentialing Program, a new...