Oregon State University researchers have designed a perovskite-based way to inkjet-print circuitry, in a precise manner and at low processing temperatures, directly onto cloth.

"Much effort has gone into integrating sensors, displays, power sources and logic circuits into various fabrics for the creation of wearable, electronic textiles," said Chih-Hung Chang, professor of chemical engineering at Oregon State. "One hurdle is that fabricating rigid devices on cloth, which has a surface that's both porous and non-uniform, is tedious and expensive, requiring a lot of heat and energy, and is hard to scale up. And first putting the devices onto something solid, and then putting that solid substrate onto fabric, is problematic too - it limits the flexibility and wearability of the fabric and also can necessitate cumbersome changes to the fabric manufacturing process itself."

KAUST researchers have developed a perovskite ink tailor-made for a mass manufacturing process called slot-die coating, producing PSCs that captured solar energy with high efficiency. The ink could also be coated onto silicon to create perovskite/silicon tandem solar cells.

The planar p-i-n device architecture of the perovskite solar cell employed in the study. Image credit: KAUST

PSCs made in research labs are typically made by spin-coating, which is unsuited to mass manufacture. Slot-die coating, in contrast, is a manufacturing technique used industrially for many years. 'The process involves continuously and precisely forcing an ink through a narrow slit that is moved across the substrate to form a continuous film,' Anand Subbiah, a postdoc in Stefaan De Wolf's lab, said. 'This high-throughput technique would allow for roll-to-roll fabrication, similar to printing newspapers.'

Researchers from Russia-based ITMO University have created a perovskite-based surface that can turn normal glass into a smart surface. The surface will also be able to convert solar energy into electricity.

"Perovskite films are successfully implemented in LED production. We want to use these films to create surfaces that could be potentially used in AR screens. They have to be transparent enough for users to be comfortable looking through them. At the same time, they have to radiate light to display the necessary information on the screen," explains Sergey Makarov, lead researcher at ITMO's Faculty of Physics and Engineering.

NREL and Energy Materials Corp. (EMC) have joined forces on a project to determine the thermal budget for the coating of perovskite films using different substrates and perovskite inks.

Supported by the U.S. Department of Energy's Solar Energy Technologies Office and Advanced Manufacturing Office, both thermal and rapid thermal processing will be studied to determine optimal device processing conditions for NREL's scalable ink and scalable processing.

Researchers at Linköping University in Sweden have announced the development of an optoelectronic magnetic double perovskite. The discovery could open the door to combining spintronics with optoelectronics for rapid and energy-efficient information storage.

The team explains that one type of perovskite that contains halogens and lead has recently been shown to have interesting magnetic properties, opening the possibility of using it in spintronics. Spintronics is thought to have huge potential for the next generation of information technology, since information can be transmitted at higher speeds and with low energy consumption. However, magnetic properties of halide perovskites have until now been associated only with lead-containing perovskites, which has limited the development of the material for both health and environmental reasons.

KAUST researchers have conducted outdoor tests, that have shown that an increase in temperature affects the performance of a tandem perovskite/silicon solar cell due to voltage losses aw well as current mismatch between the two sub-cells.

The energy yield of two-terminal tandem cells is maximized when the two sub-cells produce the same current at the maximum power point. However, when one of the two devices generates less current than the other, and current mismatch between the sub-cells occurs, the overall device's current is affected.

University of Minnesota researchers, led by Professor Russell Holmes and former CEMS Professor Eray Aydil (NYU), have succeeded in demonstrating stable heterojunctions between metal-halide perovskites and offered the first in-depth examination of interfacial mixing in these structures.

Image from ACS Energy Letters

The team explained that perovskite devices currently rely on architectures that combine the perovskite active layer with adjacent organic or oxide layers. Alternative structures based on perovskite-perovskite heterojunctions have not been widely explored due mainly to ion diffusion and mixing across the interface. In this new work, the researchers demonstrated that this challenge is not a general limitation and that perovskite-perovskite interfaces can be stable.