Researchers develop mechanically robust and self-healable perovskite solar cells

A multi-institution team of researchers, led by the Davidson School of Chemical Engineering at Purdue University, has reported a breakthrough in the flexible solar cell field that may contribute to the development of solar cells on flexible surfaces, including ultra-flexible and wearable energy-harvesting devices.

Perovskite composite material heals after mechanical damage and is demonstrated in flexible solar cells image

“Our research is unique in that we have created the first mechanically self-healing perovskite material,” says Blake Finkenauer, lead author of the study and a fourth-year graduate student with Dr. Letian Dou, the Charles Davidson Assistant Professor of Chemical Engineering at Purdue. “Self-healing mechanical damage has only been realized in the organic materials field, typically with insulating materials. By joining dissimilar perovskite and polymer materials, a composite material with both semiconducting and self-healing properties is realized. The polymer acts as a molecular bonding agent with the crystals, which improves both the thermal and mechanical stability compared to the pure perovskite material".

CITYSOLAR project to develop perovskite/OPV hybrids for photovoltaic windows

A new EU project called "CITYSOLAR" aims to revolutionize the market for transparent solar cells for windows by combining two photovoltaic (PV) technologies in a tandem configuration. The project has received 3,779,242 EUR in support from the H2020 framework programme. Transparent solar cells for windows have been known for several years, but are still not sufficiently efficient - which is what the new project will attempt to change.

“We develop new innovative concepts within light management and solar module integration that are specifically targeted at new promising organic and hybrid thin film PV technologies, and by that we go significantly beyond state-of-the-art in terms of efficiency for transparent photovoltaics. It’s a revolutionary new concept,” says Professor Aldo di Carlo, Cnr-Ism, who is coordinator of the new project and is thrilled about the support of "CITYSOLAR" from the H2020 framework.

Researchers design new method to achieve directional polarized light emission from thin‐film LEDs

Researchers from North Carolina State University and the University of Texas have developed and demonstrated a new approach for designing photonic devices. The new method enabled the team to control the direction and polarization of light from thin-film LEDs, overcoming the widely known obstacles of beam shaping that arise from their Lambertian nature. Such LEDs with directional and polarized light emission could be useful for many photonic applications.

A new approach for designing photonic devices with directional light emission image

“This is a fundamentally new device architecture for photonic devices,” says Franky So, corresponding author of a paper describing the work and Professor of Materials Science and Engineering at NC State. “And we’ve demonstrated that, using our approach, directional and polarized emissions from an organic LED or a perovskite LED without external optical elements can be realized”.

Perovskites could help to dramatically lower the cost of electron sources

Rice University scientists, in collaboration with a team from Los Alamos National Laboratory (LANL), have reported a technology that could dramatically reduce the cost of semiconductor electron sources, key components in various devices that range from night-vision goggles and low-light cameras to electron microscopes and particle accelerators.

Representation of a halide perovskite photocathode imagePerovskite semiconductors (silver) treated with a layer of cesium (blue-green) could be tuned to emit free electrons (gray) over both visible and ultraviolet spectra (colored arrows), and a layer of cesium could regenerate degraded photocathodes.

Billions of dollars are spent each year on photocathode electron sources made from semiconductors containing rare elements like gallium, selenium, cadmium and tellurium. "This should be orders of magnitude lower in cost than what exists today in the market," said study co-corresponding author Aditya Mohite, a Rice materials scientist and chemical engineer. He said the halide perovskites have the potential to outperform existing semiconductor electron sources in several ways.

Dual Passivation technique yields perovskite solar cells with 20.14% efficiency

Researchers from the Shaanxi Normal University in China have designed a perovskite solar cell based on methylammonium lead iodide (MAPbI3) through a dual passivation technique that simultaneously passivates trap defects in both the perovskite and electron transport layer (ETL) films.

“So far, most techniques for modifying perovskite solar cells focus on either the perovskite or electron transport layer,” the research group reported, noting that the ETL must have decent optical transmittance and high electron mobility to extract photo‐induced carriers and contribute to the solar cell efficiency.

Researchers provide insights into ways to improve the fundamental durability and stability of perovskite PV modules

Hunt Perovskite Technologies (HPT) recently announced the publication of its scientific article, jointly written with Colorado School of Mines and the United States Department of Energy's National Renewable Energy Laboratory.

In the article, the scientists identify and analyze the importance of perovskite thin film stoichiometry to its durability and the possible mechanisms that lead to rapid degradation of certain perovskite materials designed for use in the manufacture of photovoltaic (PV) solar cells. Their results provide key insights into ways to improve the fundamental durability and stability of perovskite PV modules.

Modifying perovskite-based solar cells with MXenes yields impressive results

A research team at NUST MISIS and the University of Tor Vergata recently presented an improved structure of perovskite solar cells. The scientists modified perovskite-based solar cells using MXenes — thin two-dimensional titanium carbides with high electrical conductivity. The MXenes-based modified cells reportedly showed superior performance, with power conversion efficiency exceeding 19% (the reference demonstrated 17%) and improved stabilized power output with respect to reference devices.

Transition metal carbides (MXenes) for efficient NiO-based inverted perovskite solar cells image

“In this work, we demonstrate a useful role of MXenes doping both for the photoactive layer (perovskite) and for the electron transport layer (fullerenes) in the structure of solar cells based on nickel oxide,” said the co-author of the paper, a researcher from the NUST MISIS Laboratory for Advanced Solar Energy, post-graduate student Anastasia Yakusheva. “On the one hand, the addition of MXenes helps to align the energy levels at the perovskite/fullerene interface, and, on the other hand, it helps to control the concentration of defects in the thin-film device, and improves the collection of photocurrent.”