The world is shifting towards renewable energy sources, and hydrogen-based technologies are gaining attention. However, a new study suggests that the conventional thinking on single atom catalysts (SACs) might be limiting their potential. Researchers have found that the metal site in SACs can be improved by pushing the limits of design, optimizing the hydrogen evolution reaction (HER), and addressing the poisoning effects of HO* and O*. This breakthrough could lead to more efficient energy storage or hydrogen production.

Single atom catalysts are catalytically active metal sites distributed at the atomic level to enhance catalytic activity. However, hydroxyl radical (HO*) and oxygen radical (O*) poisoning can alter molecules and degrade performance. In contrast, sites where hydrogen molecules don’t readily accumulate can lead to an enhancing effect of the catalyst.

Researchers have discovered that HO* poisoning, realistic H* adsorption strengths at active metal sites, and the potential HER activity at coordinating N-sites are crucial factors to consider for accurate descriptor development. By effectively modifying these factors, more efficient catalysts can be developed to improve HER activity while not relying on conventional design of metal binding sites.

The study found that hydrogen binding energy (HBE) calculation under a realistic representation of accumulated molecules (adsorption) can serve as a good predictor of HER activity. Additionally, the combination of using HBE and Gibbs free energy as descriptors for SACs provides new guidelines for those working with this catalyst design.

This work addresses the long-lasting debate on HER descriptors and provides new methods to break out of conventional limitations put on by using just hydrogen binding energy as a solo descriptor. The researchers aim to further address the limitations of HO poisoning and develop novel single- and dual-atom catalysts for different pH conditions, especially in alkaline environments.

In conclusion, this study opens up new possibilities for SACs, highlighting the importance of pushing design limits, optimizing HER, and addressing poisoning effects. By doing so, researchers can unlock the full potential of SACs and contribute to more efficient energy storage or hydrogen production.

Crime scene investigation is about to get a significant boost thanks to a groundbreaking new method for detecting gunshot residues. Researchers from the University of Amsterdam have developed a technique that converts lead particles found in gunshot residue into a light-emitting semiconductor, making it faster, more sensitive, and easier to use than current alternatives.

When a gun is fired, it leaves behind a trail of tiny lead particles on surrounding surfaces, including clothing and skin. This innovative method uses perovskite technology to detect these lead particles, producing a bright green glow that can be seen with the naked eye. The researchers have also developed a special reagent that reacts specifically with lead atoms in gunshot residue, making it an ideal tool for forensic investigations.

Forensic experts at the Amsterdam police force are already testing this new method in actual crime scene investigations. Bente van Kralingen, a forensic expert at the Amsterdam Police, explains: “Obtaining an indication of gunshot residue at the crime scene is a major advantage, helping us answer key questions about shooting incidents.”

The researchers conducted controlled experiments to validate the effectiveness of this method, using standard 9mm full metal jacket bullets and firing them from two different pistols at cotton cloth targets placed at various distances. The results revealed well-defined luminescent patterns that were clearly visible to the naked eye, even at extended distances.

This new method has significant implications for forensic investigations, as it remains effective even after extensive washing of the shooter’s hands. It also provides valuable pieces of the puzzle when reconstructing a shooting incident. However, a positive test needs to be carefully interpreted, as it does not automatically mean that you fired a gun.

The researchers believe this new method will be especially beneficial to first responders, such as police officers, who can use it to rapidly screen potential suspects and witnesses to secure crucial evidence. Beyond forensic applications, the team is also exploring the potential of this light-emitting method to detect lead contamination in environmental samples such as water and soil.

Since lead is toxic and harmful to the environment, this research could have broader implications for environmental monitoring and public health. With this new tool, investigators can now gather crucial evidence more efficiently, leading to better outcomes in real-world investigations.

The researchers at POSTECH have made a groundbreaking discovery that is set to revolutionize various industries. Led by Professor Hyoung Seop Kim, they have developed a new alloy that defies temperature limitations. This innovative material maintains its strength and ductility across an extraordinary range of temperatures, from -196 °C to 600 °C.

Most metals used in everyday life become fragile or brittle when exposed to extreme temperatures. For instance, doorknobs can feel icy in winter and scalding in summer. The conventional approach has been to optimize metal materials for performance within a narrow temperature range, which restricts their effectiveness in environments with dramatic temperature fluctuations.

To overcome this challenge, the POSTECH research team introduced the concept of the “Hyperadaptor” and developed a nickel-based high-entropy alloy (HEA) that embodies this idea. The newly created HEA exhibits remarkable stability, maintaining nearly constant mechanical performance across the wide temperature range.

The presence of nanoscale L1₂ precipitates within the alloy acts as reinforcements, inhibiting deformation while accommodating stress through consistent slip behavior regardless of temperature. This unique combination enables the alloy to withstand sudden or extreme temperature changes, making it an ideal material for applications such as rocket engines, automotive exhaust systems, power plant turbines, and pipelines.

The development holds significant promise for enhancing both safety and efficiency in these demanding environments. As Professor Kim notes, “Our HEA breaks through the limitations of existing alloys and establishes a new class of temperature-insensitive materials.” The study was supported by the Ministry of Science and ICT through the Nano and Materials Technology Development Program and by Hyundai Motor Group.

This breakthrough has the potential to transform industries that require materials with consistent mechanical behavior even under extreme conditions.