Researchers at the University of Cambridge, University of Science and Technology of China, Shanghai Jiao Tong University, Soochow University, OIST, Hong Kong University of Science and Technology, Victoria University of Wellington and Kyushu University have demonstrated efficient blue perovskite LEDs based on a mixed two-dimensional–three-dimensional perovskite and a multifunctional ionic additive that enables control over the reduced-dimensional phases, non-radiative recombination channels and spectral stability. 

The team reported a series of devices that emit efficient electroluminescence from mixed bromide/chloride quasi-three-dimensional regions, with external quantum efficiencies of up to 21.4% (at a luminance of 22 cd m^–2 and emission peak at 483 nm), 13.2% (at a luminance of 2.0 cd m^–2 and emission peak at 474 nm) and 7.3% (at a luminance of 6 cd m^–2 and emission peak at 464 nm). The devices showed a nearly 30-fold increase in operational stability compared with control LEDs, with a half-lifetime of 129 min at an initial luminance of 100 cd m^–2. 

An international collaboration between scientists from CSIRO, University of Cambridge and others has resulted in a new efficiency record for fully roll-to-roll printed solar cells.

According to the team, the cells achieved “power conversion efficiencies of up to 15.5% for individual small-area cells and 11.0% for serially-interconnected cells”.

An international group o researchers, including ones from the Fraunhofer Institute for Solar Energy Systems ISE, Solaronix, University of Cambridge, École Polytechnique Fédérale de Lausanne (EPFL) and others, have developed a method to re-manufacture fully encapsulated perovskite solar cells after recycling. According to the researchers, the re-manufactured devices can achieve 88% of their original efficiency.

The novel method for re-manufacturing perovskite solar cells (PSCs) uses carbon-based electrodes (CPSMs). Re- manufacturing, as opposed to merely recycling, is described as the combination of re-used, recycled, repaired, or replaced parts to make a new product. “In this work, we demonstrate for the first time a re-manufacturing strategy for glass-glass encapsulated perovskite solar cells,” the scientists stated. “Our study presents a facile experimental method to remove the edge-sealant, encapsulant, back electrode, and degraded perovskite, allowing reuse of the device constituents.”

Researchers at the National University of Singapore (NUS), Beijing University of Technology, Suzhou Maxwell Technologies and Technical University of Munich have developed a triple-junction perovskite/Si tandem solar cell that can reportedly achieve a certified world-record power conversion efficiency of 27.1% across a solar energy absorption area of 1 sq cm, representing the best-performing triple-junction perovskite/Si tandem solar cell thus far. To achieve this, the team engineered a new cyanate-integrated perovskite solar cell that is stable and energy efficient.

Current multi-junction solar cell technologies pose many issues, such as energy loss which leads to low voltage and instability of the device during operation. To overcome these challenges, Assistant Professor at NUS, Hou Yi, led a team of scientists to demonstrate, for the first time, the successful integration of cyanate into a perovskite solar cell to develop a novel triple-junction perovskite/Si tandem solar cell that surpasses the performance of other similar multi-junction solar cells. 

King Abdullah University of Science and Technology (KAUST) scientists, along with collaborators from Ulsan National Institute of Science and Technology (UNIST) and Chinese Academy of Sciences (CAS), have reported a new strategy to design perovskite solar cells (PSCs) that improves their stability and raises their efficiency.

Image credit: KAUST

Defects at the top and bottom interfaces of three-dimensional (3D) perovskite photo-absorbers diminish the performance and operational stability of PSCs due to charge recombination, ion migration, and electric-field inhomogeneities. In this recent work, the team demonstrated that long alkyl-amine ligands can generate near-phase pure two-dimensional (2D) perovskites at the top and bottom 3D perovskite interfaces and effectively resolves these issues.

Researchers from the University of Stuttgart, Forschungszentrum Jülich, Brandenburg University of Technology Cottbus-Senftenberg and University of Victoria have reported 'the highest open-circuit voltage recorded to date' for a single-junction perovskite solar cell based on hybrid methylamine lead chloride (MAPbCl₃). The novel perovskite absorber was fabricated with a two-step deposition method and annealing under molecular nitrogen (N₂) gas inside a glovebox.

Image from: ACS Publications

The team fabricated a single-junction transparent perovskite solar cell based on hybrid methylamine lead chloride (MAPbCl₃), a perovskite material with one of the highest energy bandgaps among all perovskites. The team stated that this new cell could open the door for wide bandgap perovskites solar cells, which will be important not just for applications like Internet-of-Things (IoT) or solar windows, but also multijunction solar cells. The new work is especially noteworthy as single junction perovskites with wide bandgaps have not yet reached high voltages before.

Researchers at HZB's HySPRINT Innovation Lab, China's Tianjin University of Technology and Tianjin Institute of Power Sources have developed a non-laser additive method for manufacturing perovskite solar modules, in which an adjustable wire mask (AWM) was used to form the channels that were traditionally scribed by lasers. 

When module channels are made by conventional laser scribing, the heat-sensitive perovskite materials decompose, and the decomposition of perovskites in the open channel leads to reduced module stability. The electrode corrosion caused by the direct contact between the exposed perovskites and the metal electrode significantly increases the series resistance of the module. In this recent work, the team developed a non-laser additive method for manufacturing perovskite solar modules, in which an adjustable wire mask (AWM) was used to form the channels that were traditionally scribed by lasers. This method for making modules prevents contact between perovskites and electrodes. All layers, including perovskites, hole/electron transporting, and passivating and electrode layers, were fabricated via vapor-phase deposition, and by tuning the precursor composition, a power conversion efficiency (PCE) of 21.7% was obtained (0.1 cm²). 

Researchers at Korea's Pusan National University, Kyungpook National University, Switzerland's École Polytechnique Fédérale de Lausanne (EPFL) and University of Fribourg have pioneered an approach that not only rectifies lead leakage but also focuses on interfacial passivation. The team used the method to achieve perovskite solar cells with 21.7% power conversion energy.

The presence of lead ions in perovskite solar cells not only causes lead leakage, which is hazardous to the environment, but in the presence of moisture, the perovskite tends to degrade. Multiple approaches have been suggested to resolve this issue, including encapsulating the device and compositional engineering of the perovskite light absorbers. The crown ether was found to assist in resisting degradation due to moisture for 300 hours at room temperature and 85 percent humidity. In the study, the researchers tested many crown ethers, but found that B18C6 was the best for interfacial passivation.

Researchers from MIT, University of Cambridge, University of Washington and Korea Research Institute of Chemical Technology have reported a set of recommendations for how to tune surface properties of perovskites - ways to optimize efficiency and better control degradation, by engineering the nanoscale structure of perovskite devices - towards the commercialization of perovskite-based solar cells.

The recent work addresses the two main hurdles that have been plaguing perovskite solar cells: their longevity and the challenge of maintaining high efficiency across larger module areas.

Researchers from Nanjing University, University of Victoria and Australian National University have achieved a high conversion efficiency of 24.5% on large-size all-perovskite tandem solar cells. The result, which the team states is a new world record for the efficiency of all-perovskite tandem solar cells, has reporetdly been confirmed by an international third-party testing institute.

When a lead-tin perovskite is used instead of silicon as the narrow band gap cell in all-perovskite tandem solar cells, the result is often low film quality and device efficiency due to nonuniform nucleation and fast crystallization. In this recent work, the team shows that aminoacetamide hydrochloride can strongly coordinate the precursor components in solution, which homogenizes the crystallization process and also passivates the buried perovskite interface. The authors achieved a certified power conversion efficiency of 24.5% for a 20-square-centimeter module made by blade-coating the layers.