The inherent interdependence among the device footprint, resolution, and bandwidth of spectrometers poses a challenge for further miniaturization of on-chip spectrometers. Scientists in China report an ultra-miniaturized chaos-assisted spectrometer that breaks the trade-off limitation of current spectrometers. Optical chaos is introduced into the spectrum via cavity deformation. By utilizing a single chaotic cavity, chaotic behavior can be employed to effectively eliminate periodicity in resonant cavities and de-correlate the response matrix. A broad operational bandwidth of 100 nm can be attained with a high spectral resolution of 10 pm. Additionally, the footprint of the spectrometer is compacted to a mere 20×22 μm², in the meantime addressing the three-way trade-off of resolution-bandwidth-footprint metric in prior-art spectrometers.

Scanning near-field optical microscopy encounters difficulties in characterizing sub-10-nm confined light fields due to significant disturbances of the optical field caused by the probe. Here, by employing a high spatial-resolved photoemission electron microscopy, we succeeded in imaging the ultra-confined near fields of a nanoslit mode in a coupled nanowire pair with weak disturbance. Meanwhile, a PEEM image can identify fabrication defects that are influential to the confined field but are imperceptible to many other means.

High costs have long held back hydrogen production from water, with electrolyzers priced at $2,000–$2,600 per kilowatt in 2024. Now, researchers from Japan have found that modifying platinum cathodes with naturally occurring purine bases can boost the hydrogen evolution reaction (HER) activity, the key step where water is split into hydrogen, up to four times. This approach can significantly reduce platinum requirements, bringing affordable, large-scale hydrogen production closer to reality.

Anode-free metal batteries offer high energy densities, but suffer from dendritic growth and short circuits, arising from non-uniform metal deposition. To address this, researchers from South Korea have developed a new facet-driven metal plating strategy that employs a facet-oriented zinc (Zn) host with a physicochemically polished surface to ensure uniform, horizontal Mg growth during plating, preventing dendrite formation and improving stability.

Understanding molecular diversity is fundamental to biomedical research and diagnostics, but existing analytical tools struggle to distinguish subtle variations in the structure or composition among biomolecules. A new method using solid-state nanopores — tiny tunnels that a protein or other molecule can pass through — and machine learning suggests a way to help identify and classify proteins more accurately.

With the rapid development of two-dimensional MXene materials, numerous preparation strategies have been proposed to enhance synthesis efficiency, mitigate environmental impact, and enable scalability for large-scale production. The compound etching approach, which relies on cationic oxidation of the A element of MAX phase precursors while anions typically adsorb onto MXene surfaces as functional groups, remains the main prevalent strategy. By contrast, synthesis methodologies utilizing elemental etching agents have been rarely reported. Here, we report a new elemental tellurium (Te)-based etching strategy for the preparation of MXene materials with tunable surface chemistry. By selectively removing the A-site element in MAX phases using Te, our approach avoids the use of toxic fluoride reagents and achieves tellurium-terminated surface groups that significantly enhance sodium storage performance. Experimental results show that Te-etched MXene delivers substantially higher capacities (exceeding 50% improvement over conventionally etched MXene) with superior rate capability, retaining high capacity at large current densities and demonstrating over 90% capacity retention after 1000 cycles. This innovative synthetic strategy provides new insight into controllable MXene preparation and performance optimization, while the as-obtained materials hold promises for high-performance sodium-ion batteries and other energy storage systems.

Lignins – the complex molecules that make plants sturdy and allow them to grow tall – are not as random as once thought. A new international study led by Prof. Edouard Pesquet at Stockholm University uncovers how lignins’ chemistry and structure vary between cell types to meet plants’ physiological needs. The paper, published as a Tansley Review in the journal New Phytologist, highlights how this molecular diversity has been key to plants’ success on land.