Perovskite-based sensors can help detect harmful pesticides and toxins

Various dangerous chemicals are currently used for agriculture and industry, including fumigants like methyl iodide, which is used to control insects and fungi. The wrong amounts or incorrect use of these fumigants can be harmful to people and degrade the ozone layer. As it’s invisible and doesn’t smell, it’s hard to tell whether there are dangerous amounts of methyl iodide present, and until now the best way to test for it was in a laboratory using expensive, complicated equipment, which isn’t practical in many real-world settings. Some cheaper, lightweight detection methods have been tried, but they didn’t have enough sensitivity and took too long to deliver results.

Perovsite aid in detecting chemical warfare agents and pesticides image

Now, a research team led by the ARC Centre of Excellence in Exciton Science, along with Australia’s national science agency CSIRO and the Department of Defense, has found a perovskite-based way to detect methyl iodide, with the accuracy, flexibility and speed necessary for practical use. This new sensing mechanism is also versatile enough for use in detecting a wide range of fumigants and chemical warfare agents.

KAUST team develops micropump fluidic strategy for fabricating perovskite microwire devices embedded in semiconductor platforms

King Abdullah University of Science and Technology (KAUST) researchers have shown how fluid injection of perovskite semiconductors creates microwires to build different optoelectronic devices on a single silicon chip. They have developed a microfluidic pumping technology that can help perovskites be more readily incorporated into silicon-based semiconducting platforms.

The ''lab on a chip'' designed at KAUST imageThe "lab on a chip" designed at KAUST consists of several perovskite-based optoelectronic devices on one silicon chip, embodying a photodetector, transistor, light-emitting diode and a solar cell, for example. Credit: KAUST and Techxplore

Compared to traditional semiconductors, perovskites are soft and unstable. "This makes it difficult to pattern them using standard lithography methods," says materials scientist Iman Roqan at KAUST. The challenge tackled by Roqan and her colleagues was to adapt microfluidic technologies to manipulate solutions carrying perovskites to create semiconducting microscale wires.

International team improves perovskite solar cells using cesium-titanium dioxide nanotubes

An international research team, which included researchers from Pakistan, China and Saudi Arabia, has developed a perovskite solar cell with strong thermal stability and enhanced electron injection by using special nanotubes made of cesium-titanium dioxide (Cs-TiO2).

The scientists used titanium sheets with 99.4% purity, 1 mm thickness, and a length of 50 mm. The cell was fabricated with a two-step electrochemical anodization process and was then encapsulated with Cs nanoparticles, after being doped with a Cs-based solution. The C2-TiO2 nanotubes were then annealed at 450 C. The solar cell is based on methylammonium lead triiodide (CH3NH3PbI3), which is a perovskite with high photoluminescence quantum yield.

Researchers develop a new model to assess the internal luminescence quantum efficiency of perovskite films

A group of researchers at Germany's Karlsruhe Institute of Technology (KIT), the University of Heidelberg and the Technical University of Dresden have developed a new model to reliably and precisely determine the photoluminescence quantum yield of perovskite layers.

In their new paper, the research team shows how the novel method they developed can determine the photoluminescence quantum yield under solar irradiation conditions more precisely than previously assumed. “It depends on the photon recycling, that is, the proportion of the photons emitted by the perovskite that is reabsorbed within the thin layers and re-emitted again, KIT scientist Paul Fassl explained.

CEA-INES researchers report 18% power conversion efficiency for perovskite solar modules

A team of researchers at the French National Solar Energy Institute (INES) at the country’s Alternative Energies and Atomic Energy Commission (CEA) has announced achieving 18% power conversion efficiency of perovskite solar modules.

They were able to achieve this level on an active surface area of 10 cm² under illumination of 1 STC sun, using a coating step carried out in air followed by a gas quenching conversion step to form the desired perovskite material. This material was developed without methyl ammonium comprising multi-cations and a mix of halogens.