Article last updated on: Jan 08, 2018
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.

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.

Perovskite solar cell market image

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.

Perovskite solar cell image

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 calculate that a 32% perovskite/silicon tandem cell solar will still be competitive at triple the price

Researchers from Arizona State University’s Fulton Schools of Engineering have calculated that a 32% efficient perovskite-silicon tandem cell could produce electricity at the same price as cutting-edge 22% efficient panels in the most cost-competitive of situations.

ASU team finds that a 32% tandem cell solar still competitive at triple the price

The paper specifies: “…a large cost benefit will not necessarily be needed to prefer tandem systems over single-junction systems, because higher efficiencies bring additional perceived benefits such as reduced installation area. It is, however, necessary that the path leading to such a tandem be continuously profitable.”

German scientists track perovskite defects to increase efficiency

A team of researchers from the University of Potsdam and HZB has identified loss processes in perovskite solar cells that limit their efficiency, and found that the most significant efficiency losses occur at the interface between the perovskite and transport layer.

SOLAR German scientists observe perovskite defects to increase cell efficiencies image

In certain defects in the crystal lattice of the perovskite layer, charge carriers (i.e. electrons and "holes") that have been released by sunlight can recombine again and thus be lost. But whether these defects were located within the perovskite layer or at the interface between the perovskite layer and the transport layer was unclear until now.

Graphene for the Display and Lighting Industries

University of Washington team boosts performance quality of perovskites

Researchers at the University of Washington report that a prototype perovskite thin-film has performed even better than today’s best solar cell materials at emitting light. “It may sound odd since solar cells absorb light and turn it into electricity, but the best solar cell materials are also great at emitting light,” said co-author and UW chemical engineering professor Hugh Hillhouse. “In fact, typically the more efficiently they emit light, the more voltage they generate.”

UW researchers boost performance quality of perovskites imagea back-reflector A back-reflector surface used to test perovskite performance. Each quadrant is a different surface material — gold, titanium, palladium or a silica compound — upon which the perovskite material would be deposited for experiments

The UW team achieved a record performance using a lead-halide perovskite, by chemically treating it through a process known as “surface passivation,” which treats imperfections and reduces the likelihood that the absorbed photons will end up wasted rather than converted to useful energy.

Imec hits 27.1% efficiency with its new perovskite-silicon tandem PV cell

Imec, the leading research and innovation hub in nanoelectronics, energy and digital technology, within the partnership of EnergyVille, announced a record result for its 4-terminal perovskite/silicon tandem photovoltaic cell. In fact, with a reported power conversion efficiency of 27.1%, the new tandem cell tops the most efficient standalone silicon solar cell. Further careful engineering of the Perovskite material will bring efficiencies over 30% in reach.

Imec’s new record tandem cell uses a 0.13 cm² spin-coated perovskite cell developed within the Solliance cooperation, stacked on top of a 4 cm² industrial interdigitated back-contact (IBC) silicon cell in a 4-terminal configuration, which is known to have a higher annual energy yield compared to a 2-terminal configuration. Additionally, scaling up the tandem device by using a 4 cm2 perovskite module on a 4 cm2 IBC silicon cell, a tandem efficiency of 25.3% was achieved, surpassing the stand-alone efficiency of the silicon cell.

Russian scientists design a new method of creating perovskite films for cells

Researchers at the Moscow State University named after MV Lomonosov, in cooperation with scientists from the Kurchatov Synchrotron Radiation Center, explained the key mechanisms of interaction of hybrid perovskites with solvents and based on the results obtained, suggested new approaches to obtaining a perovskite light-absorbing layer of thin-film solar cells from weakly coordinating aprotic solvents.

Russian scientists design a new method of creating perovskite films for cells imageThe scheme of transformations of perovskite components in solution proposed by the authors of the study

To apply thin films of perovskite from solutions, two solvents are usually used: dimethylsulfoxide and dimethylformamide. However, earlier work of MSU scientists showed that crystallization from them proceeds through the formation of intermediate compounds – crystal solvates, which can degrade the morphology and functional properties of the perovskite layer.