Perovskite News - Page 1

Researchers at the Energy Research Center of the Netherlands (ECN) have developed a bifacial tandem solar cell with a conversion efficiency of 30.2%. The new cell device – created with Dutch consortium Solliance – was made by applying a newly developed perovskite cell on top of an industrial bifacial crystalline silicon version.

This approach, according to the scientists, enables a significantly higher power conversion efficiency as one cell is optimized for high energy photons, and the other low energy particles. “The tandem device proposed here uses a four-terminal configuration, thus having separate circuits for the top and bottom cells that allow for dynamic fine tuning and optimization of the energy yield,” the creators of the cell wrote. The cell is also said to be better able to capture light on its front and rear sides by responding to the variability of incident light through its electronic design.

Researchers at the Japanese Kanazawa University aim to improve the performance of perovskite solar cells by using two kinds of titanium oxide - anatase and brookite.

The team claims to have reached a conversion efficiency of 16.82% in a perovskite cell by applying a brookite layer made of water-solute brookite nanoparticles on an anatase layer. This reportedly helps to improve the transport of electrons from the center of the cell to its electrodes, while also preventing charges from recombining at the border between the perovskite material and the electron transport layer. “Together, both these effects allow us to achieve higher solar cell efficiencies,” said the research coordinator, Md. Shahiduzzaman.

The following post is a sponsored post by MBRAUN

Prof. Dr. Steve Albrecht and his 11-member team of the Helmholtz Innovation Lab HySPRINT at
Helmholtz-Zentrum Berlin (HZB) develop tandem solar cells that combine the advantages of silicon
and perovskite solar cells. In order to create the best research conditions, Prof. Albrecht had installed
systems from the market leaders, MBRAUN and CreaPhys (a part of MBRAUN).

HySPRINT Perovskite Lab © HZB / M. Setzpfandt

The Perovskite cluster is composed of 4 different parts: Precursor synthesis, wet coating with spin coater, evaporation of perovskites and metallization, scaling with inkjet printer and slot die coater under laminar flow. Every part of the cluster is integrated in inert gloveboxes under inert atmosphere to guarantee the best performance of the devices, as well as the best repeatability of the processes.

Researchers at MIT, ETH Zurich and Empa have made major steps toward finding a photon source with constant, predictable, and steady characteristics. In the quest to develop practical computing and communications devices based on the principles of quantum physics, such a source of individual particles of light is extremely desirable. The study involves using perovskites to make light-emitting quantum dots.

Scanning Transmission Electron Microscope image (STEM) of single perovskite quantum dots

The ability to produce individual photons with precisely known and persistent properties, including a wavelength, or color, that does not fluctuate at all, could be useful for many kinds of proposed quantum devices. Since each photon would be indistinguishable from the others in terms of its quantum-mechanical properties, it could be possible, for example, to delay one of them and then get the pair to interact with each other, in a phenomenon called interference.

Researchers from HZB, Oxford University, Technical University Berlin and Oxford PV have shown that the infrared reflection losses in tandem cells processed on a flat silicon substrate (such as perovskite/silicon tandem cells) can be significantly reduced by using an optical interlayer, consisting of nanocrystalline silicon oxide. Based on this, the team managed to achieve impressive efficiency and reported that the best tandem device in this work reached a certified conversion efficiency of 25.2%.

a) Cross-section of the simulated monolithic perovskite/SHJ tandem cell (layer thicknesses and morphological features not to scale). b) Cross-sectional SEM image of the top region of the tandem device.

Perovskite/silicon tandem solar cells are attractive for their potential for boosting cell efficiency beyond the crystalline silicon (Si) single-junction limit. However, the relatively large optical refractive index of Si, in comparison to that of transparent conducting oxides and perovskite absorber layers, often results in significant reflection losses at the internal junction between the cells in monolithic (two-terminal) devices. Therefore, light management is crucial for improving photocurrent absorption in the Si bottom cell.

Brazilian state-run oil major Petroleo Brasileiro, or Petrobras, has signed a partnership deal with Centro de Inovacoes CSEM Brazil to develop materials for the production of printed and flexible solar cells based on perovskite technology.

Under the research and development (R&D) agreement, Petrobras will invest BRL 23.77 million (USD 6.2 million/EUR 5.6 million) over a 30-month period. The main goal is the production of a prototype module and obtaining the know-how needed to make the industrial production of solar films with perovskite technology technically and economically viable.

A team of scientists from Washington University in St. Louis, Oak Ridge National Laboratory and University of Missouri studied the structure and properties of the commonly occurring planar defects at the atomic scale of lead halide perovskite.

When these materials are made, defects can occur where different crystals meet, known as grain boundaries. In conventional semiconductors, these defects can decrease their electrical conductivity and the solar energy-to-electricity conversion efficiency; however, in lead-halide perovskites, there are differing experimental reports on the activity of grain boundaries. In some cases, they are found to be harmful, while in other cases they either have no impact on performance or are even beneficial. But, to date, no one understood why. The research team in this work set out to discover these reasons.