August 2017

A team of researchers from the University of Sheffield, alongside collaborators from the universities of Kent, Nottingham and Leicester, has investigated and confirmed the potential for Perovskite solar cells (PSCs) in addressing global environmental challenges.

The team compared PSCs with other existing photovoltaic technologies, including an examination of the kind of materials used in their production, the difficulty of manufacturing them, and costs involved in producing and manufacturing them. They also carried out a systematic hybrid life cycle assessment of PSCs, meaning that every aspect associated with PCSs, including greenhouse gas emission, material use, land use, pollution and toxicology, was considered.

Researchers from North Carolina State University have used perovskites to significantly boost the efficiency of a technique that splits carbon dioxide (CO₂) to create carbon monoxide (CO). The CO₂-splitting process reportedly converts more than 98% of the CO₂ into CO. In addition, the process also uses the resulting oxygen to convert methane into syngas, which is itself a feedstock used to make fuels and other products.

For the CO₂-splitting process, researchers developed a nanocomposite of strontium ferrite dispersed in a chemically inert matrix of calcium oxide or manganese oxide. As CO₂ is run over a packed bed of particles composed of the nanocomposite, the nanocomposite material splits the CO₂ and captures one of the oxygen atoms. This reduces the CO₂, leaving only CO which is valuable because it can be used to make a variety of chemical products, including everything from polymers to acetic acid.

A team of Chinese and US scientists from Shenzhen Institute of Technology, Shijiazhuang Tiedao University, Peking University, Argonne National Laboratory, Institute of Metal Research, and University of Washington, have grown a monocrystalline version of a perovskite solar cell.

The created cell is reportedly of high quality and firmly incorporated on FTO/TiO2. To create it, the team has taken advantage of capillary effect and temperature gradient during the growth process. This achievement is considered to be critical, since FTO/TiO2 is regarded as the most extensively used electron-collecting substrate for perovskite solar cells, making the succeeding device fabrication straightforward. Although it won't replace monocrystalline silicon cells anytime soon (the new cell's efficiency is only 9%), it's the first time perovskite has been grown as a single cell.

A multi-disciplinary team of scientists has shown that 2D organic-inorganic hybrid materials feature far fewer defects than thicker 3D versions.

Modern-day electronics rely on technologies that can develop almost perfect crystals of silicon; flawless to the atomic level. This is crucial because defects and impurities scatter electrons as they flow, which adversely affects the material's electronic properties. But hybrid perovskites cannot be constructed using the epitaxial or layer methods developed for silicon. Instead, they are produced using solution-based processes. While this makes them cheaper than silicon, it also makes purity much harder to achieve as defect population and species are sensitive to the processing conditions.

Researchers at the Okinawa Institute of Science and Technology Graduate University (OIST) have reported findings that may help improve perovskite-based technology in the entire energy cycle.

The new findings suggest interactions between components of the solar cell itself are responsible for the rapid degradation of the device. More precisely, the titanium oxide layer extracting electrons made available through solar energy ' effectively creating an electric current ' causes unwanted deterioration of the neighboring perovskite layer. To prevent exactly that, the OIST researchers inserted an additional layer made from a polymer to prevent direct contact between the titanium oxide and the perovskite layers. This polymer layer is insulating but very thin, which means it lets the electron current tunnel through yet does not diminish the overall efficiency of the solar cell, while efficiently protecting the perovskite structure.

GreatCell Solar, the Australia-based materials company formerly called Dyesol, has been awarded a AUS$6m (around $4.75 million USD) grant from the Australian Renewable Energy Agency (ARENA) for the Perovskite Solar Cell Technology - Large Area Module Development Project.

The company has also set out to raise around $5 million AUS ($4 million USD) as part of the project funding. This should enable Greatcell to accelerate the scale-up and prototyping activities to commercialize the company's technology.

Researchers from The University of Manchester have reported a new method that makes use of polystyrene particles (rather than expensive polymers) to reduce the costs and improve the stability of next-gen perovskite-based solar cells.

PSCs that use organometallic halide perovskite (OHP) as a light absorber face a known challenge of material degradation when exposed to water. This makes practical use quite limited. The cells also rely on a hole-transportation layer, which promotes the efficient movement of electrical current after exposure to sunlight. But manufacturing the hole-transportation organic materials is very costly and these lack long-term stability. This is where the use of insulating polystyrene microgel particles comes in.

We are happy to announce a new Metalgrass knowledge hub, MicroLED-Info.com. This new site will focus on Micro-LED display technology and its future market. MicroLED is quickly becoming a promising future display technology.

Many expect the first Micro-LED devices to hit the market in the very near future, with first applications in the wearable market - and also in HUDs and HMDs. MicroLED promise great performance, very high efficiency and brightness - but of course there are still many technical challenges ahead.

Researchers from Washington University recently described a novel technique to fabricate perovskite solar cells, using an aerosol-based technique called electrospray deposition.

In the first step, PbI2 is deposited onto a TiO2-coated, fluorine-doped tin oxide glass substrate by spin coating to form a nearly uniform, yellow coating. Next, a solution of methyl ammonium iodide (MAI) is electrosprayed by pumping it through a capillary needle at a high voltage and generating monodispersed charged droplets in Taylor cone-jet mode. The charged droplets travel in the electric field toward the grounded substrate and the solvent from these droplets evaporates before reaching the substrate. The dry MAI nanoparticles then react with the PbI2 layer to form the dark brown colored perovskite. The perovskite formation can be achieved in 40 minutes with optimized MAI concentration, flow rate, and substrate-to-needle distance.

Researchers from Ludwig-Maximilians-Universitaet (LMU) in Munich and the Johannes Kepler University (JKU) in Austria have designed a method to tune the color of the light emitted by a LED by altering the size of its semiconductor crystals.

The method enables the production of semi-conducting nanocrystals of defined size based on perovskites. The crystals are extremely stable, which ensures that the LEDs exhibit high color fidelity ' an important criterion of quality. Moreover, the resulting semiconductors can be printed on various surfaces, and are thus promising for the manufacture of LEDs for use in displays.