October 2022

Scientists from the Ural Federal University (UrFU) and the Institute of Organic Synthesis of the Ural Branch of the Russian Academy of Sciences (along with their colleagues) have proposed a new type of material for transporting electrons in perovskite solar cells, which has a number of advantages.

The team reported that with the new material, they were able to achieve solar energy conversion efficiency of 12%. "The family of molecules we found carries electrons in PSCs slightly worse than the fullerenes used today, but they are about twice as cheap, much easier to produce, and have a number of other technological advantages," says Gennady Rusinov, associate professor at the Department of Organic Synthesis Technology of UrFU.

Researchers at the University of Helsinki are developing thin films for perovskite solar cells, and matching ALD processes. 

Doctoral Researcher Georgi Popov focuses on perovskites and atomic layer deposition (ALD). In 2019, He and his colleagues identified suitable chemicals and were able to design a reaction that enabled them to create a metal iodide coating through deposition for the first time. The researchers were able to demonstrate that this can actually be done through atomic layer deposition. The first successful trial was carried out with lead iodide, which was then processed into CCH₃NH₃PbI₃ perovskite through a further reaction. Later on, the researchers also developed ALD processes for caesium iodide and CsPbI₃ perovskite. 

Chinese perovskite solar technology company Renshine Solar (Suzhou) has announced achieving steady-state efficiency of 24.50% for all-perovskite tandem cell module, which it called 'a world record'.

It was reported that the efficiency was achieved for a perovskite module with an area of 20.25 cm², which exceeds that of perovskite single-junction components. The new efficiency level has been certified by Japan’s JET, it added without sharing other details.

Researchers from China's Huazhong University of Science and Technology and Singapore's National University of Singapore have introduced an eco-friendly and low-cost organic polymer, cellulose acetate butyrate (CAB), to the grain boundaries and surfaces of perovskites, resulting in a high-quality and low-defect perovskite film with a nearly tenfold improvement in carrier lifetime.

The CAB-treated perovskite films have a well-matched energy level with the charge transport layers, thus suppressing carrier nonradiative recombination and carrier accumulation. As a result, the optimized CAB-based device achieved a champion efficiency of 21.5% compared to the control device (18.2%).

Researchers from Helmholtz-Zentrum Berlin (HZB) and Potsdam University have reported perovskite–silicon tandem solar cells with periodic nanotextures that offer various advantages without compromising the material quality of solution-processed perovskite layers. Textured tandem devices have been presented before, aiming at improved optical performance, but optimizing film growth on surface-textured wafers has thus far remained challenging.

The research team showed a reduction in reflection losses in comparison to planar tandems, with the new devices being less sensitive to deviations from optimum layer thicknesses. The nanotextures also enabled a greatly increased fabrication yield from 50% to 95%. Moreover, the open-circuit voltage was improved by 15 mV due to the enhanced optoelectronic properties of the perovskite top cell. The optically advanced rear reflector with a dielectric buffer layer resulted in reduced parasitic absorption at near-infrared wavelengths. As a result, the team achieved a certified power conversion efficiency of 29.80%.

Researchers from Empa, EPFL, Sichuan University, Jiaxing University, Soochow University, University of Cologne, University of Potsdam, HZB and the University of Oxford have developed a flexible all-perovskite tandem solar cell with a mitigated open-circuit voltage deficit and reduced voltage loss. The team reported flexible tandem efficiency of almost 24% on small area cells using the spin coating method.

Flexible all-perovskite tandem cells are currently less developed than rigid cells, due to a difficult deposition process for the cell's functional layers and a lower open-circuit voltage. This is due to high defect densities within the perovskite absorber layer and at the perovskite/charge selective layer interface.

Researchers from Ulsan National Institute of Science and Technology (UNIST), Wuhan University of Technology and Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory have manufactured high efficiency, stable, and scalable perovskite solar cells (PSCs) via vacuum deposition, a method of fabricating organic light-emitting display devices (OLEDs). 

In their study, the research team demonstrated efficient and stable PSCs with a vacuum-processed Ruddlesden-Popper (RP) phase perovskite passivation layer. By controlling the deposition rate of the RP phase perovskite, which directly influenced its crystallographic orientation, the research team successfully obtained a highly ordered 2D perovskite passivation layer.

Researchers from China's Jilin University have designed a spray coated spherical perovskite photonic sensor made of phenyl ethyl ammonium/formamidinium lead halide (PEA₂FAn_-1Pb_nX_3n+1). The researchers utilized the perovskite formulations to regulate the crystallization rate. Cyclic spray-coating and the solution concentration were used to control the coating thickness from a few nanometers to hundreds of micrometers. 

Sphere imagers featuring specific wavelength recognition and wide-angle imaging are required in order to meet the fast development pace of modern technology. However, it remains challenging to deposit high-quality photosensitive layers on sphere substrates from low-cost solution processes. In this recent study, the team demonstrated the feasibility of using a rapid spray-coating procedure to fabricate perovskite hemispherical photodetectors that can execute lens-free scanning at nearly 180°, considerably decreasing the reliance on complex optical components.

A team of scientists, led by Professor Hairen Tan of Nanjing University, has demonstrated (for was the team states is the first time) bifacial all-perovskite monolithic tandem solar cells and examined their output power potential.

The research team demonstrated the design and fabrication of bifacial all-perovskite tandem solar cells using transparent conductive oxide (TCO) as the back electrode. The bandgap technique of the top subcell was used to obtain current matching under different backlights. The influence of the albedo on the photovoltaic parameters and the spectral sensitivity was systematically investigated. The bifacial tandems reportedly showed a high output power density of 28.51 mW cm⁻² under a realistic rear illumination (30 mW cm^{− 2}). Further energy yield calculation showed substantial energy yield gain for bifacial tandems compared with the monofacial tandems under various ground albedo for different climatic conditions. This work provides a new device architecture for higher output power for all-perovskite tandem solar cells under real-world conditions.

The perovskite industry is rapidly moving towards commercialization and mass production. Here are some recent and popular news that you may find of interest:

• Wuxi UtmoLight announces 18.2% efficiency for large area perovskite solar module
• Hanwha Q Cells plans to mass-produce perovskite tandem cells by 2026
• Solliance team breaks 30% efficiency barrier for a 4T silicon-perovskite tandem device
• Researchers create optical fibers made from single-crystal organometallic perovskite
• Researchers fabricate flexible roll-to-roll perovskite solar cells with 16.7% efficiency
• Researchers achieve 31.25% efficiency for tandem perovskite-silicon solar cell
• Stores in Poland use perovskite shelf labels and blinds by Saule technologies
• Researchers use perovskites to design more environmentally friendly air conditioners
• DaZheng announces commercialization of large flexible perovskite solar panels
• NREL team highlights the potential of perovskites for renewable hydrogen production
• When will perovskite solar panels hit the market?
• TENG+Perovskite solar cell generates electricity from both sunlight and falling raindrops
• Oxford PV completes build-out of its Brandenburg factory
• JinkoSolar announces a 30% perovskite cell technology platform
• Saule Technologies launches its production line of perovskite solar panels