Researchers report new perovskite-based synapse-like phototransistor

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 secures DOE funding

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).

New design could lead to high-efficiency all-back-contact perovskite solar cells

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.

The new perovskite architecture opens the surface up to allow more sunlight to be absorbed imagePhoto 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 .

New perovskite LED emits a circularly polarized glow

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.

New spin-LED emits a circularly polarized glow image

“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.”

Unique method yields 23.2% efficient perovskite solar cells

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.