As the climate crisis becomes a part of daily life with unprecedented heatwaves and cold snaps, technology to effectively remove greenhouse gases is emerging as a critical global challenge. In particular, catalytic technology that decomposes harmful gases using oxygen is a key element of eco-friendly purification. South Korean researchers have identified the principle that catalysts—which were previously vaguely thought to simply ‘use oxygen well’—can selectively utilize different oxygen sources depending on the reaction environment, presenting a new standard for catalyst design.

Zinc–air chemistry is uniquely suited for microscale energy storage because it uses oxygen directly from the surrounding air, reducing the need for stored reactants. Despite this advantage, true micrometre-scale zinc–air batteries based on interdigitated electrodes and operating in safe, near-neutral electrolytes have remained largely unexplored. Most existing designs are primary batteries or rely on stacked architectures and strongly alkaline electrolytes, limiting their suitability for biomedical applications and on-chip integration.

Researchers have now developed a planar micro zinc–air battery that overcomes these challenges. The device integrates bifunctional cathode catalysts, a near-neutral NH₄Cl/ZnCl₂-based gel electrolyte, and micrometre-scale interdigitated electrodes patterned in a single plane. Using electrodeposition and microplotter-assisted microfabrication, precise material coverage is achieved across 200-micrometre-wide electrodes. Despite its small footprint, the battery delivers high energy and power at elevated current densities and is capable of powering an LED and a digital thermometer. This demonstrates that chip-scale systems can host their own onboard power source, enabling fully autonomous micro-devices.

The work is the result of a two-institution collaboration: Tata Institute of Fundamental Research (TIFR) Hyderabad, India, led catalyst chemistry, materials development, and electrochemistry, while University College London (UK) contributed micro-fabrication, micro-plotting, and device engineering expertise.

As a first demonstration, challenges remain. Long-term cycling leads to gradual material loss at both anode and cathode, resulting in capacity decay. Ongoing efforts focus on robust catalyst anchoring, improved bifunctional cathode materials, and suppression of zinc dendrites to enhance areal energy and power over extended operation. This advance opens pathways for micro-batteries in wearables, implantable sensors, IoT nodes, and soft microrobotics, where power sources must be as small and integrated as the devices themselves.

Engineers have long known that powerful lasers can make metals stronger. For decades, a technique called laser shock peening has been used to extend the lifetime of aircraft engines, railway components, and other critical parts by blasting their surfaces with intense laser pulses. The treatment leaves metals better able to resist fatigue, wear, and corrosion—key requirements in extreme environments.

What has received far less attention, however, is how long the laser pulse duration last.

In the International Journal of Extreme Manufacturing, researchers demonstrate that laser pulse duration, from nanoseconds down to femtoseconds, fundamentally changes how laser shock peening works. By analyzing nearly 300 studies published over the past six decades, the team shows that timing, not just power, may define the future of laser-based metal strengthening.

Graphene and diamond sit at opposite ends of the materials spectrum, yet they are made from the same element. One is a single layer of carbon atoms that bends easily and carries electrical current with little resistance. The other is among the hardest materials known, prized for its strength, chemical stability and ability to conduct heat. For years, engineers have wondered whether it might be possible to combine the best of both worlds.

In the International Journal of Extreme Manufacturing, a new review by researchers at Shanghai Jiao Tong University now lays out how far that idea has come. The team surveys the growing field of graphene–diamond hybrids, materials that physically or chemically link the two carbon forms to create performance combinations that neither can achieve alone.

Osaka Metropolitan University researchers conducted a preliminary study of the relevant challenges, divergence, and instabilities of an e-beam in an ionospheric atmosphere and identified them quantitatively through numerical simulations.