February 2021

A team of researchers at the French National Solar Energy Institute (INES) at the country's Alternative Energies and Atomic Energy Commission (CEA) has announced achieving 18% power conversion efficiency of perovskite solar modules.

They were able to achieve this level on an active surface area of 10 cm² under illumination of 1 STC sun, using a coating step carried out in air followed by a gas quenching conversion step to form the desired perovskite material. This material was developed without methyl ammonium comprising multi-cations and a mix of halogens.

A team of researchers at MIT (along with colleagues from South Korea and Georgia) has developed a new approach to the design of perovskite cells by adding a specially treated conductive layer of tin dioxide bonded to the perovskite material, which provides an improved path for the charge carriers in the cell. By also modifying the perovskite formula, the researchers have reportedly boosted its overall efficiency as a solar cell to an impressive 25.2%.

On top of many other attractive properties, perovskites have a higher bandgap than silicon, which means they absorb a different part of the light spectrum and thus can complement silicon cells to provide even greater combined efficiencies. But even using only perovskite, MIT's Jason Yoo says, 'what we're demonstrating is that even with a single active layer, we can make efficiencies that threaten silicon, and hopefully within punching distance of gallium arsenide. And both of those technologies have been around for much longer than perovskites have.'

Scientists at the Helmholtz-Zentrum Berlin have improved a process for vertically depositing a solution made from an inexpensive perovskite solute onto a moving substrate placed below. Not only have they discovered the crucial role played by one of the solvents used, but they have also taken a closer look at the aging and storage properties of the solution.

The liquid solution of perovskite precursor, solvent, and additive flows from a slit-shaped nozzle onto the glass substrate being conveyed below. Credit: Jinzhao Li / HZB

The perovskite solar cells that Prof. Eva Unger and her team at the Helmholtz-Zentrum Berlin (HZB) are researching seem to be extremely promising. 'These are the best solar cells to date that can be made using a 2D ink', the researcher explains. 'And now their efficiencies are approaching those for cells made of crystalline silicon.'

Five Wrocław University of Science and Technology researchers have been awarded over than 12 million PLN (around USD$3.2 million) for research projects under the Maestro and Sonata Bis competitions organized by the National Centre for Science. Among the research area are perovskites, active enzymes, and artificial intelligence.

Targeting experienced scientists, Maestro is a competition for research projects aimed at carrying out pioneering, and also interdisciplinary, research that is important for the development of science and reaching beyond the current state of knowledge, which may result in scientific discoveries.

Scientists at The University of Manchester have developed a way to increase the environmental safety of perovskite solar cells by eliminating the lead release from broken cells. Using a bioinspired mineral called hydroxyapatite, a major constituent of human bone, they have created a 'failsafe' which captures the lead ions in an inorganic matrix. As a result, if cells are damaged, toxins are stored in an inert mineral, rather than released in the environment.

Unlike silicon solar cells, perovskite solar cells can be mass produced through roll-to-roll processing. Additionally, they are light and can be used in non-traditional settings such as windows and contoured roofs. However, up until now, application has been impacted by potential environmental risks. Perovskite solar cells contain lead, a cumulative toxin, and if the cells get damaged, lead ions may leak.

AMOLF researchers Erik Garnett, Susan Rigter, and colleagues have demonstrated that amorphous perovskite exists. The material can significantly increase the efficiency of solar cells produced from perovskite.

Perovskites are naturally crystalline; in other words, the atoms pack together in an ordered pattern. From traditional silicon solar cells, we know that the efficiency of the cells can be boosted if a part of the material is amorphous, meaning the atoms pack together randomly. Erik Garnett from AMOLF was reportedly the first to realize that amorphous perovskite could fulfill the same function. The following challenge was to produce the material and study its properties. Garnett explains why that was difficult: 'Perovskite consists of ions. By nature, these easily organize in a crystal lattice, just like table salt, for example. We needed to come up with a trick to prevent those crystals from forming, and we managed to do just that. Using techniques such as X-ray diffraction, we subsequently also demonstrated that the material is amorphous. With this, we delivered the first irrefutable evidence that amorphous perovskite exists.'

A team of scientists,  led by László Forró from the School of Basic Sciences at the Ecole Polytechnique Federale de Lausanne (EPFL) in Switzerland, has developed a new X-Ray Photodetector based on perovskites and graphene.

Using 3D aerosol jet-printing technology, the team designed a new technique for creating highly efficient x-ray photodetectors that can be easily added to standard microelectronic circuits, creating more powerful medical imaging devices that can deliver better scan qualities.

The U.S. Air Force recently awarded the University of Toledo (UToledo) $12.5 million to develop photovoltaic energy sheets that would live in space and harvest solar energy to transmit power wirelessly to Earth-based receivers or to other orbital or aerial instrumentation, such as communications satellites.

UToledo physicists will develop flexible solar cell sheets, each roughly the size of a piece of paper, that can be assembled and interconnected into much larger structures. The team will focus on tandem architectures and work with a variety of combinations of solar cells, perovskites included.

Scientists from South Korea have developed a foldable thin-film device with promising characteristics. Integrating a perovskite cell material and a carbon nanotube electrode, the group fabricated a device that achieved 15.2% efficiency and could be folded more than 10,000 times at a bending radius of 0.5mm.

Solar cell materials tend to be quite sensitive. Designing and manufacturing devices that can withstand the stress of being folded and bent is challenging, and many of even the most promising solutions are still quite limited in their flexibility. The scientists at Pusan National University in South Korea took a major step forward in solving this problem, fabricating a device that can be folded down to a 'bending radius' ' the minimum size of fold possible without causing damage ' of 0.5mm.

Power Roll, a developer of low-cost and lightweight flexible film for energy generation and storage, recently reported raising £3 million (around USD$4.16 million), which joins a previous raise and takes total investment in the firm to £5.8 million (over USD$8 million) over two funding rounds completed in the last six months.

Power Roll is working with a perovskite solar ink, and has already achieved 11% efficiency, with a roadmap to bring this to 20%. Power Roll also states that its substrate is compatible with any photo absorbing ink.