NREL - Page 4

Researchers from the University of North Carolina have developed a mini perovskite solar module with a power conversion efficiency of up to 19.3% efficiency based on a novel approach for interface engineering.

The new device was created using a new technique for stabilizing the embedded perovskite-substrate interfaces in the solar cells. Common approaches, the researchers explained, had previously focused on stabilizing perovskite-metal electrode interfaces through surface passivation or post-fabrication treatment. 'Degradation of perovskite solar cells starts from the interfaces, including both perovskite-metal electrodes and perovskites-substrates, where defects enrich,' the team stated in the new paper. 'Stabilizing the embedded bottom interfaces is as important as that of [the] top interface.'

The Department of Energy recently awarded $14 million to form a center, led by Sandia National Laboratories, to improve the understanding of perovskite-based photovoltaic technologies and determine the best tests to evaluate the new solar panels' lifetimes.

Perovskite-based photovoltaic technologies still have several challenges to overcome before they can compete against conventional solar panels. The Perovskite Photovoltaic Accelerator for Commercializing Technologies Center aims to offer solutions to these challenges.

Researchers at the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) have reported a breakthrough in energy-efficient phototransistors - devices that could someday help computers process visual information similarly to the human brain and be used as sensors in applications like self-driving vehicles.

The structures rely on metal-halide perovskites. Jeffrey Blackburn, a senior scientist at NREL and co-author of a new paper outlining the research, said: 'In general, these perovskite semiconductors are a really unique functional system with potential benefits for a number of different technologies'. 'NREL became interested in this material system for photovoltaics, but they have many properties that could be applied to whole different areas of science.'

Hunt Perovskite Technologies (HPT) recently revealed that it has been selected for an award of $2.5 million in financing from the United States Department of Energy's (DOE) Office of Energy Efficiency & Renewable Energy Solar Energy Technologies Office Fiscal Year 2020 Perovskite Funding Program.

In addition, HPT is also co-Principle Investigator and collaborative partner in two other DOE perovskite funding award selections, including a $1.5 million award to SLAC National Accelerator Laboratory and a $1.25 million award to University of North Carolina at Chapel Hill (UNC).

Researchers from the National Renewable Energy Laboratory (NREL) have found that restructuring the way perovskite solar cells are designed can boost their efficiency and increase their deployment in buildings. Their newly proposed architecture for the cells increases the area exposed to the sun by putting the metal contact layers side-by-side on the back of the cell.

Photo by Kevin Prince/NREL

'Taking the materials on top away means you are going to have a higher theoretical efficiency because your perovskite is absorbing more of the sun,' said Lance Wheeler, a NREL scientist .

A team of researchers from the National Renewable Energy Laboratory (NREL) and the University of Utah has developed a new type of LEDs that utilizes spintronics without needing a magnetic field, magnetic materials or cryogenic temperatures.

'The companies that make LEDs or TV and computer displays don't want to deal with magnetic fields and magnetic materials. It's heavy and expensive to do it,' said Valy Vardeny, distinguished professor of physics and astronomy at the University of Utah. 'Here, chiral molecules are self-assembled into standing arrays, like soldiers, that actively spin polarize the injected electrons, which subsequently lead to circularly polarized light emission. With no magnetic field, expensive ferromagnets and with no need for extremely low temperatures. Those are no-nos for the industry.'

Scientists from the University of North Carolina have developed a perovskite solar cell with an efficiency of 23.2% by adding benzylhydrazine hydrochloride (BHC) as an iodine (I) reductant agent in precursor solutions such as methylammonium iodide (MAI) and formamidinium iodide (FAI).

'Preventing the degradation of perovskite precursor solutions is equally important compared to post-fabrication device encapsulation, because large-area perovskite modules are generally manufactured in air and perovskite precursor inks are generally prepared in large quantity and stored for days or months,' the scientists said.

Researchers from UCLA, NREL, The University of Toledo, Yangzhou University, Soochow University, Monash University and Lawrence Berkeley National Laboratory, have found that perovskites have a previously unutilized molecular component that can further tune the electronic property of perovskites.

Schematic of perovskite material with organic molecules that can add to its electronic properties. Credit: Jingjing Xue and Rui Wang/UCLA Samueli School of Engineering

Perovskite materials have a crystal-lattice structure of inorganic molecules like that of ceramics, along with organic molecules that are interlaced throughout. Up until now, these organic molecules appeared to only serve a structural function and would not directly contribute to perovskites' electronic performance.

Researchers at HZB have published their recent work, reporting its current world record of 29.15% efficiency for a tandem solar cell made of perovskite and silicon. The tandem cell provided stable performance for 300 hours ' even without encapsulation. To accomplish this, the group, headed by Prof. Steve Albrecht, investigated physical processes at the interfaces to improve the transport of the charge carriers.

In the beginning of 2020, a team headed by Prof. Steve Albrecht at the HZB broke the previous world record for tandem solar cells made of perovskite and silicon (28.0%, Oxford PV), setting a new world record of 29.15%. Compared to the highest certified and scientifically published efficiency, this is a significant step forward. The new value has been certified at Fraunhofer ISE and listed in the NREL chart. Now, the results have been published in the journal Science with a detailed explanation of the fabrication process and underlying physics.

Scientists at the National Renewable Energy Laboratory (NREL) have investigated how to manufacture perovskite materials and solar technology with human health in mind.

Newly published research points to the safest choices for solvents needed to make perovskite solar cells. Unlike silicon solar panels, which require an industrial process, perovskite solar panels can be made using chemicals and produced using a roll-to-roll printing method or spray coating. The process also costs less and takes less time than manufacturing silicon panels.