Researchers design flexible X-Ray detectors based on molecular perovskites

Researchers from China's University of Science and Technology of China (USTC) and Shaanxi Normal University have synthesized a new molecular perovskite, DABCO-CsBr3 (DABCO = N,N′-diazabicyclo[2.2.2]octonium), for use in flexible X-ray detectors. The material was prepared from DABCO, CsBr, and HBr in aqueous solution and obtained in the form of colorless crystals.

The team found that DABCO-CsBr3 possesses good mechanical properties for use in flexible devices. Compared with the metal-free equivalent DABCO-NH4Br3, DABCO-CsBr3 has a stronger X-ray attenuation capability. The researchers built a flexible X-ray detector, using a poly(vinylidene fluoride) (PVDF) polymer matrix that was mixed with DABCO-CsBr3 to create a composite film. This film shows a linear relationship between the X-ray-induced current density and the X-ray dose rate. According to the team, the material could have applications in X-ray security screening systems or medical diagnostics.

Read the full story Posted: Jul 19,2022

TubeSolar and ZSW reach milestone on the way to industrializing flexible perovskite solar cells

TubeSolar, together with the Centre for Solar Energy and Hydrogen Research Baden-Württemberg (ZSW), has reached an important milestone on the way to industrial production of its novel photovoltaic technology: an efficiency record of 14% was achieved on solar films in the industrially suitable "roll-to-roll" process. This was achieved as part of TubeSolar's perovskite research activities. 

In the process, the partners deposited all layers - with the exception of the front and rear contacts - using slot die. The speed of the coating process was over one metre per minute. The combination of this industrially suitable, fast production process and the high efficiency was referred to as 'groundbreaking' by the Companies. The flexible solar cells are used for the production of tubular photovoltaic modules, which can be used in agri-photovoltaics, among other applications.

Read the full story Posted: Jul 18,2022

Researchers develop strain relaxation approach to improve the stability of quasi-2D perovskite solar cells

A research team, led by Prof. Zhou Huiqiong's group from the National Center for Nanoscience and Technology (NCSNT) of the Chinese Academy of Sciences (CAS), has developed a strain relaxation strategy to study the effect of residual strain on properties of quasi-two-dimensional (2D) perovskites. 

The introduction of hydrophobic spacer cations makes quasi-2D perovskites more stable compared with traditional 3D perovskites, but the stability of perovskites remains unsatisfactory. Residual strain is closely related to the crystallographic properties, which in turn can significantly affect the photovoltaic properties and stability of perovskites. The research team investigated the residual strain in quasi-2D perovskite with mixed spacer cations by X-ray diffraction (XRD) and atomic force microscope (AFM). They found that there is severe tensile strain along the out-of-plane direction in pristine perovskite film, leading to poor crystallinity and insufficient stability issues. With an appropriate composition of spacer cations, the tensile strain is effectively released.

Read the full story Posted: Jul 16,2022

The Solar Energy Research Institute of Singapore (SERIS) upgrades equipment towards industrial production of perovskite-silicon tandem solar cells

The Solar Energy Research Institute of Singapore (SERIS) at the National University of Singapore (NUS) announces that it will upgrade its "Spatial Atomic Layer Deposition" (SALD) equipment. SoLayTec and SERIS have been working closely together for over a decade in the field of silicon solar cells. Recently, SERIS stated that SoLayTec will upgrade its existing ALD system using the latest technology of SALD BV, a Dutch technology start-up, for development of scalable perovskite-silicon tandem solar cells.

"Upgrading to the new SALD equipment brings us significant advantages," explains Dr. Shubham Duttagupta, Deputy Director of the Next-Generation Industrial Solar Cells & Modules Cluster at SERIS. The Dutch company SALD BV has developed a patented technology for applying precise coatings on an industrial scale that can be as thin as a single atom. An atomically thin coating, as can be achieved with the SALD technology, can make the cells significantly more robust. SERIS wants to take the leap “from lab to fab” with the new SALD machine. 

Read the full story Posted: Jul 16,2022

DOE announces $56 Million to advance U.S. solar manufacturing

The Biden-Harris Administration, through the U.S. Department of Energy (DOE), has announced new initiatives and $56 million in funding to promote innovation in solar manufacturing and recycling. The funding will aim to help make clean energy more affordable and reliable, create jobs and enhance U.S. economic growth and competitiveness. Developing more solar power, the cheapest form of new electricity supply, is key to achieving President Biden’s goal of 100% clean electricity by 2035.

The new programs that were announced are designed to drive innovation in solar technology and manufacturing, supporting opportunities for the U.S. to expand production of thin-film modules, which do not rely on foreign-dominated supply chains, as well as supporting newer technologies like perovskite solar cells.

Read the full story Posted: Jul 15,2022

Researchers develop four-terminal tandem perovskite/CIGS solar cell with 26.2% efficiency

Scientists from the University of Tokyo have reported a 26.2% power conversion efficiency for a four-terminal tandem solar cell based on perovskite and copper, indium, gallium and selenium (CIGS). The researchers said these results are a world record for such tandem solar devices and attributed the improvements to the performance of the perovskite top cell.

They built the 1-square-centimeter perovskite device using a transparent conductive material made of indium tin oxide (ITO), which was deposited via sputtering and without thermally evaporated Molybdenum oxides ( MoOx). “By eliminating the use of the MoOx buffer layer, we were able to develop semi-transparent PVK cells with higher durability and transmittance,” the scientists said.

Read the full story Posted: Jul 15,2022

Swansea University and Tata Steel launch perovskite solar project

Tata Steel UK and Swansea University are collaborating on a project for solar roofing panels that can be printed on the steel used in buildings. The solar roofing panels would enable buildings to generate, store and release their own secure electricity supply. This could reduce the use of fossil fuels and alleviate pressure on the National Grid.

Named ‘Active Buildings’, the concept has reportedly shown success in the operation of two buildings on the Swansea University campus for several years. The new research aims to explore the technology’s potential further and accelerate the process of turning it into products for industry to manufacture.

Read the full story Posted: Jul 14,2022

Researchers examine the environmental performance of perovskite-on-silicon tandem solar cells

A team of scientists from Technische Universität Berlin, Oxford PV Germany, German Philipps-Universität Marburg, Helmholtz Zentrum Berlin (HZB) and Oxford PV UK has, for the first time, assessed the environmental performance of industrially produced perovskite-on-silicon PV modules. Understanding the environmental impact of solar PV modules across their entire lifecycle is essential for the design of more sustainable solar energy systems. However, lifecycle assessment of perovskite-on-silicon PV modules has so far relied heavily on data from laboratory and test facilities rather than manufacturers.

The researchers conducted a comprehensive lifecycle assessment of a perovskite-on-silicon module across a number of categories including global warming potential, water consumption, human and marine toxicity, and metals usage. They assessed the materials and energy input for a module’s ‘cradle to gate’ lifecycle, covering all materials and energy input for wafer production, manufacture of the perovskite cell, and module production. The researchers then weighed up the environmental impact of the tandem module against the electricity generated over its lifetime.

Read the full story Posted: Jul 11,2022

Researchers design two-terminal all-perovskite tandem solar modules with a 19.1% efficiency

Researchers at the Karlsruhe Institute of Technology (KIT) in Germany have fabricated a spin-coated, two-terminal, all-perovskite tandem solar module with an aperture area of 12.25 square centimeters and a geometric fill factor of 94.7%. The team said that laser-scribed two-terminal all-perovskite tandem (2TPT) solar cells have attracted attention in recent years, as they combine a wide bandgap perovskite top subcell with a narrow-bandgap perovskite bottom subcell.

The scientists used a 23-5% efficient 2TPT solar cell based on perovskite and copper/indium/selenium (CIS) thin-film, which they first announced in June. It has an open-circuit voltage of 1.59 V, a short-circuit current of 19.4 mA cm–2, and a fill factor of 75.5%.

Read the full story Posted: Jul 11,2022

Novel spectroscopic approach for assessing the impact of chemical alterations of the A-cation on perovskite electronic structure

Researchers from Uppsala University, Stockholm University, Deutsches Elektronen-Synchrotron DESY, KTH Royal Institute of Technology and Tata Institute of Fundamental Research have used the element selectivity of high-resolution X-ray spectroscopy and density functional theory to uncover a previously hidden feature in the conduction band states, the σ-π energy splitting, and found that it is strongly influenced by the strength of electronic coupling between the A-cation and bromide-lead sublattice.

These findings provide an alternative mechanism to the commonly discussed polaronic screening and hot phonon bottleneck carrier cooling mechanisms. The new work emphasizes the optoelectronic role of the A-cation, provides a comprehensive view of A-cation effects in the crystal and electronic structures, and outlines a broadly applicable spectroscopic approach for assessing the impact of chemical alterations of the A-cation on perovskite electronic structure. 

Read the full story Posted: Jul 10,2022