Efficiency - Page 45

Researchers at Arizona State University have demonstrated a perovskite-silicon tandem cell they claim has low reflectance losses and strong potential for commercial production. The ASU team says that this new cell could lead to 30% efficiency tandem devices. The tandem architecture involves a manufacturing process featuring the solution-based blading of perovskites onto textured silicon wafers.

Image credit: Joule

The device is manufactured in a nitrogen-assisted blading process which ensures deposition of the perovskite layer onto textured silicon is achieved with typical pyramid heights of 1μm. The manufacture of such tandem devices typically results in perovskite heights of 3-10μm.

Researchers from Helmhotlz-Zentrum Berlin (HZB), collaborating with teams from University of Cambridge, Eindhoven University of Technology, Nicolaus Copernicus University, Salerno University and others, have developed a monolithic "two-terminal" tandem cell made of CIGS and perovskite that achieved a certified efficiency of 24.16%, with a thickness of well below 5 micrometers - which would allow the production of flexible solar modules.

Tandem cells combine two different semiconductors that convert different parts of the light spectrum into electrical energy. Metal-halide perovskite compounds mainly use the visible parts of the spectrum, while CIGS semiconductors convert rather the infrared light. CIGS cells, which consist of copper, indium, gallium and selenium, can be deposited as thin-films with a total thickness of only 3 to 4 micrometers; the perovskite layers are even much thinner at 0.5 micrometers.

This article is an extract from The Perovskite Handbook, 2020 edition, and explains the current market status of Perovskites Solar Panels.

Solar Panels is the most prominent potential perovskite application, as synthetic perovskites are recognized as inexpensive base materials for high-efficiency commercial photovoltaics. Perovskite PVs are constantly undergoing research and improvement, going from just 2% in 2006 to over 23% today, and constantly improving. Experts forecast that the market for perovskite PV will reach $214 million in 2025.

Power efficiency is obviously a key metric for solar power technologies. In this article we'll explain how solar system efficiency is defined and the current power efficiency market status of PSCs.

Researchers from Australia's ARC Center of Excellence in Exciton Science, Monash University, Wuhan University of Technology and CSIRO Energy have shown how critical imperfections invisible to the naked eye can be detected by shining blue light onto the cells and recording the infrared light that bounces back.

Perovskite solar cells bathed in blue light, and responding in infrared. Credit: Exciton Science

This "trick of the light" may help detect imperfections in perovskite solar cells, opening the door to improved quality control for commercial production.

An international research team has developed a new type of solar cell that can both withstand environmental hazards and is 26.7% efficient in power conversion.

Structure and photovoltaic performance for the perovskite-Si tandem device. Image by KAIST

The researchers, led by Byungha Shin, a professor from the Department of Materials Science and Engineering at KAIST, focused on developing a new class of light-absorbing material, called a wide bandgap perovskite. The material has a highly effective crystal structure that can process the power needs, but it can become problematic when exposed to environmental hazards, such as moisture. Researchers have made some progress increasing the efficiency of solar cells based on perovskite, but the material reportedly has greater potential than what was previously achieved.

Scientists from the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia and University of Toronto, have developed a perovskite-silicon tandem solar cell which they claim showed excellent operational stability under accelerated tests.

The device was made by combining solution-processed, micrometer-thick perovskite top cells with fully textured silicon heterojunction bottom cells.

Researchers at The Australian National University (ANU) have announced an impressive achievement - a silicon/perovskite tandem solar cell with a conversion efficiency of 27.7%.

Professor Kylie Catchpole says this would only need to improve slightly - to around 30% - before the technology could be rolled out around the world. "In comparison, typical solar panels being installed on rooftops at the moment have an efficiency around 20%" Professor Catchpole said.

Researchers from Colorado University in Boulder with the US Department of Energy's National Renewable Energy Laboratory (NREL) have shown how a change in chemical composition managed to boost the longevity and efficiency of a perovskite solar cell.

The new formula reportedly enabled the solar cell to resist a stability problem that has so far thwarted the commercialization of perovskites. The problem is known as light-induced phase-segregation, which occurs when the alloys that make up the solar cells break down under exposure to continuous light.

Researchers from Peking University in China have developed a manufacturing method for perovskite solar cells using a pre-nucleation technique. Compared to traditional solvent dripping methods, the approach enables the creation of smaller crystallites in the perovskite films as uncontrolled crystallite growth affects the efficiency and durability of cells.

The technique aims to avoid the efficiency loss caused by humidity linked to the interactions of ambient water and oxygen with the perovskite precursors and substrate used during cell production.

Italian researchers from two Italian institutions claim to have developed a two-terminal tandem perovskite-silicon solar cell with a conversion efficiency 26.3%.

The researchers added graphene to the titanium dioxide electron selective layer used in a perovskite solar cell to increase chemical stability. The two-terminal cell was made by stacking two sub-cells which were fabricated and optimized separately. The new device blends the advantages of thin-film perovskite and silicon-based heterojunction cells, according to its developers.