Perovskite Solar

What are perovskite?

Perovskites are a class of materials that share a similar structure, which display a myriad of exciting properties like superconductivity, magnetoresistance and more. These easily synthesized materials are considered the future of solar cells, as their distinctive structure makes them perfect for enabling low-cost, efficient photovoltaics. They are also predicted to play a role in next-gen electric vehicle batteries, sensors, lasers and much more.

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How does the PV market look today?

In general, Photovoltaic (PV) technologies can be viewed as divided into two main categories: wafer-based PV (also called 1st generation PVs) and thin-film cell PVs. Traditional crystalline silicon (c-Si) cells (both single crystalline silicon and multi-crystalline silicon) and gallium arsenide (GaAs) cells belong to the wafer-based PVs, with c-Si cells dominating the current PV market (about 90% market share) and GaAs exhibiting the highest efficiency.

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Thin-film cells normally absorb light more efficiently than silicon, allowing the use of extremely thin films. Cadmium telluride (CdTe) technology has been successfully commercialized, with more than 20% cell efficiency and 17.5% module efficiency record and such cells currently hold about 5% of the total market. Other commercial thin-film technologies include hydrogenated amorphous silicon (a-Si:H) and copper indium gallium (di)selenide (CIGS) cells, taking approximately 2% market share each today. Copper zinc tin sulphide technology has been under R&D for years and will probably require some time until actual commercialization.

What is a perovskite solar cell?

An emerging thin-film PV class is being formed, also called 3rd generation PVs, which refers to PVs using technologies that have the potential to overcome current efficiency and performance limits or are based on novel materials. This 3rd generation of PVs includes DSSC, organic photovoltaic (OPV), quantum dot (QD) PV and perovskite PV.

A perovskite solar cell is a type of solar cell which includes a perovskite structured compound, most commonly a hybrid organic-inorganic lead or tin halide-based material, as the light-harvesting active layer. Perovskite materials such as methylammonium lead halides are cheap to produce and relatively simple to manufacture. Perovskites possess intrinsic properties like broad absorption spectrum, fast charge separation, long transport distance of electrons and holes, long carrier separation lifetime, and more, that make them very promising materials for solid-state solar cells.

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Perovskite solar cells are, without a doubt, the rising star in the field of photovoltaics. They are causing excitement within the solar power industry with their ability to absorb light across almost all visible wavelengths, exceptional power conversion efficiencies already exceeding 20% in the lab, and relative ease of fabrication. Perovskite solar cells still face several challenge, but much work is put into facing them and some companies, are already talking about commercializing them in the near future.

What are the advantages of Perovskite solar cells?

Put simply, perovskite solar cells aim to increase the efficiency and lower the cost of solar energy. Perovskite PVs indeed hold promise for high efficiencies, as well as low potential material & reduced processing costs. A big advantage perovskite PVs have over conventional solar technology is that they can react to various different wavelengths of light, which lets them convert more of the sunlight that reaches them into electricity.

Moreover, they offer flexibility, semi-transparency, tailored form factors, light-weight and more. Naturally, electronics designers and researchers are certain that such characteristics will open up many more applications for solar cells.

What is holding perovskite PVs back?

Despite its great potential, perovskite solar cell technology is still in the early stages of commercialization compared with other mature solar technologies as there are a number of concerns remaining.

One problem is their overall cost (for several reasons, mainly since currently the most common electrode material in perovskite solar cells is gold), and another is that cheaper perovskite solar cells have a short lifespan. Perovskite PVs also deteriorate rapidly in the presence of moisture and the decay products attack metal electrodes. Heavy encapsulation to protect perovskite can add to the cell cost and weight. Scaling up is another issue - reported high efficiency ratings have been achieved using small cells, which is great for lab testing, but too small to be used in an actual solar panel.

A major issue is toxicity - a substance called PbI is one of the breakdown products of perovskite. This is known to be toxic and there are concerns that it may be carcinogenic (although this is still an unproven point). Also, many perovskite cells use lead, a massive pollutant. Researchers are constantly seeking substitutions, and have already made working cells using tin instead. (with efficiency at only 6%, but improvements will surely follow).

What’s next?

While major challenges indeed exist, perovskite solar cells are still touted as the PV technology of the future, and much development work and research are put into making this a reality. Scientists and companies are working towards increasing efficiency and stability, prolonging lifetime and replacing toxic materials with safer ones. Researchers are also looking at the benefits of combining perovskites with other technologies, like silicon for example, to create what is referred to as “tandem cells”.

Commercial activity in the field of perovskite PV

In September 2015, Australia-based organic PV and perovskite solar cell (PSC) developer Dyesol declared a major breakthrough in perovskite stability for solar applications. Dyesol claims to have made a significant breakthrough on small perovskite solar cells, with “meaningful numbers” of 10% efficient strip cells exhibiting less than 10% relative degradation when exposed to continuous light soaking for over 1000 hours. Dyesol was also awarded a $0.5 million grant from the Australian Renewable Energy Agency (ARENA) to commercialize an innovative, very high efficiency perovskite solar cell.

Also in 2015, Saule Technologies signed an investment deal with Hideo Sawada, a Japanese investment company. Saule aims to combine perovskite solar cells with other currently available products, and this investment agreement came only a year after the company was launched.

Latest Perovskite Solar news

Researchers develop method for more stable all-perovskite tandem solar cells

Researchers at The University of Toledo (UToledo), Northwestern University and University of Washington have focused on the stability of perovskite solar cells, and reported an adjustment to the chemical structure of a key component of a tandem cell that allows it to continuously generate electricity for more than 1,000 hours.

Image from Joule

“State-of-the-art all-perovskite tandem cells with a conventional hole-transfer layer can only continuously operate for hundreds of hours,” said Dr. Zhaoning Song, a co-author and assistant professor in the Department of Physics and Astronomy at UToledo. “Our innovation prolongs the stability of these devices, advancing all-perovskite tandem technology and bringing it closer to practical application.”

Read the full story Posted: Jul 16,2024

Researchers develop a crystal capping layer to enable the formation of black-phase FAPbI3 perovskites in humid air

Researchers from Peking University, Tsinghua University, Beijing Institute of Technology and Ecole Polytechnique Fédérale de Lausanne (EPFL) have tackled a reproducibility challenge in black-phase formamidinium lead iodide (α-FAPbI3) perovskites. They explained that while this is the desired phase for photovoltaic applications, water can trigger formation of photoinactive impurity phases such as δ-FAPbI3. The team found that the classic solvent system for perovskite fabrication exacerbates this reproducibility issue. 

Growth of the photoactive black phase of formamidinium lead iodide (α-FAPbI3) usually requires dimethyl sulfoxide solvent, but the hygroscopic nature of this chemical also promotes water-induced degradation to the photoinactive phase. the scientists showed that a larger chlorinated organic molecule can form a hydrophobic capping layer that enables perovskite crystallization under humid conditions by protecting growing crystallites from water. 

Read the full story Posted: Jul 13,2024

Researchers design efficient inverted perovskite solar cells using a synergistic bimolecular interlayer

A team of researchers, led by the Fudan University in China, has developed a p-i-n structure inverted perovskite solar cell that uses a synergistic bimolecular interlayer (SBI) and achieves what the team says is the smallest nonradiative recombination induced open-circuit voltage loss ever reported. 

Schematic illustration of p-i-n PSC using MPA/PEAI as SBI. Image from Nature Communications

The researchers' SBI strategy consisted of depositing 4-methoxyphenylphosphonic acid (MPA) and 2-phenylethylammonium iodide (PEAI) as modulators to functionalize the perovskite surface.

Read the full story Posted: Jul 13,2024

Researchers show how 2D perovskitoids enhance stability in perovskite solar cells

Researchers from Northwestern University, University of Toronto and KAUST have hypothesized that perovskitoids, with robust organic-inorganic networks enabled by edge- and face-sharing, could impede ion migration. This addresses the issue of the migration of cations between 2D and 3D layers which results in the disruption of octahedral networks that leads to degradation in performance over time

The scientists explored a set of perovskitoids of varying dimensionality, and found that cation migration within perovskitoid/perovskite heterostructures was suppressed compared to the 2D/3D perovskite case. Increasing the dimensionality of perovskitoids improves charge transport when they are interfaced with 3D perovskite surfaces – the result of enhanced octahedral connectivity and out-of-plane orientation. 

Read the full story Posted: Jul 11,2024

Researchers develop efficient 2D Dion-Jacobson perovskite solar cell based on MXene contacts

Researchers at India's Chitkara University Institute of Engineering and Technology have developed 2D perovskite solar cells with MXene materials to build a PV device with remarkable efficiency and open-circuit voltage. The scientists claim the new cell architecture can help charge carriers move smoothly through the cell layers and reduce recombination losses.

The team's 2D DJ perovskite solar cell implemented bandgap grading techniques and use contacts based on a functionalized two-dimensional titanium carbide known as MXene. MXenes are compounds that take their name from their graphene-like morphology and are made via selective etching of certain atomic layers from a bulk crystal known as MAX. Recently, MXenes materials have shown promise for use in PV technology due to their unique optoelectronic properties, such as their large charge carrier mobility, excellent metallic conductivity, high optical transmittance, and tunable work function (WF).

Read the full story Posted: Jul 10,2024

BOE to invest over USD$100 million in new perovskite PV pilot line

Reports suggest that a new pilot line for the production of perovskite solar cells has been approved by the administrative committee of Xinzhan Hi-Tech Zone, Hefei City, Anhui Province, China. 

The project is initiated by Hefei BOE PV Company, a holding subsidiary of BOE Technology Group Co. (BOE), a company that is known to have launched a project to enter the photovoltaic industry by investing in perovskite solar cells. BOE reportedly plans to invest 871 million yuan (approximately US$119.85 million) to set up the pilot line for perovskite solar cells. 

Read the full story Posted: Jul 09,2024

Researchers use high-entropy hybrid perovskites to design efficient and stable perovskite solar cells

Researchers from China's Zhejiang University, Westlake University, Southern University of Science and Technology, Chinese Academy of Sciences (CAS) and University of California Los Angeles in the U.S have reported a family of high-entropy organic–inorganic hybrid perovskites for photovoltaic applications.  

The scientists built, for the first time, an inverted perovskite solar cell relying on a high-entropy hybrid perovskite material. The result is a device with an improved open-circuit voltage and fill factor, due to reduced non-radiative recombinations and optimized interface.

Read the full story Posted: Jul 07,2024

Researchers improve the stability of perovskite solar cells with novel encapsulation method

Researchers at CHOSE (Centre for Hybrid and Organic Solar Energy, University of Rome Tor Vergata), BeDimensional, Istituto Italiano di Tecnologia and GreatCell Solar Italia recently addressed the stability issues presented by perovskite solar cells, by developing an industrial encapsulation process based on the lamination of highly viscoelastic semi-solid/highly viscous liquid adhesive atop perovskite solar cells and modules. 

Sketch of the structure of the mesoscopic n-i-p PSCs. Image credit: Nature Communications 

The encapsulant reportedly reduces the thermomechanical stresses at the encapsulant/rear electrode interface. The addition of thermally conductive two-dimensional hexagonal boron nitride into the polymeric matrix improves the barrier and thermal management properties of the encapsulant. Without any edge sealant, encapsulated devices withstood multifaceted accelerated ageing tests, retaining >80% of their initial efficiency.

Read the full story Posted: Jul 06,2024

Researchers develop perovskite solar cells with improved performance using an organic electron-rich surface passivation layer

Researchers from Zhejiang University of Technology and King Abdullah University of Science and Technology (KAUST) have utilized two sulfone-based organic molecules known as diphenylsulfone (DPS) and 4,4′-dimethyldiphenylsulfone (DMPS) to passivate absorber defects in perovskite solar cells and improve their performance. As a result, the team reported a device with a higher electron cloud density at the interface between the perovskite material and the passivation layer.

The scientists used the molecules to improve charge distribution at the interface between the cell's perovskite absorber and the passivation layer, which reportedly creates electron-rich systems on the surface of perovskite. Using density functional theory (DFT) to compute a wide variety of properties of almost any kind of atomic system, they simulated the charge density distributions of the interactions of DPS and DMPS with formamidinium lead iodide (FAPbI3) perovskite material.

Read the full story Posted: Jul 05,2024

Researchers design 4T perovskite/perovskite/silicon triple-junction tandem solar cell with 31.5% efficiency

Researchers from King Abdullah University of Science and Technology (KAUST) have reported four-terminal perovskite/perovskite/silicon triple-junction tandem solar cells, with the device structure comprising a perovskite single-junction top cell and monolithic perovskite/silicon tandem bottom cell.

The cells reportedly yielded a 31.5% power conversion efficiency, which the team said is the highest efficiency ever reported for perovskite-based 4-T and triple-junction tandem solar cells. The key feature of the cell is the hole transport layer of the top perovskite cell, which was engineered with self-assembled monolayers.

Read the full story Posted: Jul 03,2024