The deployment of proton exchange membrane water electrolysis (PEMWE) necessitates efficient, stable, and low-Ir electrocatalysts for acidic oxygen evolution reaction (OER) at the anode. Herein, an IrO_x/Ir-Co₃O₄ heterostructure electrocatalyst is developed featuring bulk-doped Ir-Co₃O₄ with surface-anchored IrO_x, synthesized via a facile two-step electrochemical co-deposition process followed by programmed annealing. The IrO_x/Ir-Co₃O₄ catalyst requires an overpotential of only 237 mV to reach 10 mA/cm² and achieves a high mass activity of 230 A/g_Ir at 1.5 V versus RHE. In a 1 cm² membrane electrode assembly electrolyzer (Pt/C∥IrO_x/Ir-Co₃O₄), a cell voltage of only 1.773 V delivers 1 A/cm², with stable operation exceeding 160 h at 200 mA/cm². Moreover, a 100 cm² IrO_x/Ir-Co₃O₄ anode was fabricated, exhibiting performance comparable to that of its 1 cm² counterpart. Structural and computational analyses reveal that the synergy between bulk-doped Ir-Co₃O₄ and surface anchored IrO_x optimizes the electronic structure, thereby enhancing both catalytic activity and durability. This work provides a viable and scalable pathway for developing low-Ir electrocatalysts for practical PEMWE applications.

For decades, the mathematical backbone of high-precision Global Navigation Satellite System (GNSS) positioning has rested on a Gaussian assumption that rarely holds in the real world. 

Plants produce an enormous array of chemical compounds to defend themselves against insects, herbivores, and pathogens. 

A research team has shown that combining genomic information with low-cost drone-derived phenomic data can improve the prediction of key yield traits in potato breeding. 

Hypersonic vehicles and reusable spacecraft demand lightweight thermal protection systems that can withstand extreme heat while mitigating electromagnetic wave radiation, yet single-scale ceramic architectures typically sacrifice one function for another. Now, researchers have developed a multiscale SiC fiber/nanowire aerogel that breaks this performance trade-off. Inspired by traditional Chinese papermaking, the team combined a scalable room-temperature ceramic papermaking process with high-temperature chemical vapor infiltration (CVI) to fabricate hierarchical aerogels with an ultralow density of 0.23 g·cm^-3, a minimum reflection loss of −46.62 dB, and the ability to limit back-surface temperatures to ~250 °C under a 1000 °C flame. Remarkably, prolonged ablation triggers a “fire-strengthening” effect that simultaneously enhances mechanical strength and expands the effective absorption bandwidth from 4.6 GHz to 11.5 GHz—covering 72% of the 2–18 GHz range and fully spanning the C, X, and Ku bands. This work provides a new paradigm for next‑generation extreme‑environment thermal protection materials.

Thermal-barrier coatings rely on ceramic layers that limit heat flow to metal components. A team studying (Gd_1−xSm_x)TaO₄ (GST-x) found that the conventional Klemens-Abeles parameter peaks near x = 0.5. However, room-temperature lattice thermal conductivity is lowest at x = 0.8. From GST-0 to GST-0.8, mean sound velocity fell by about 20%, while conductivity dropped by nearly one-third. Ultrasonic measurements and first-principles calculations linked most of the decline to acoustic softening. Comparison with GST-1 also suggests additional point-defect scattering from Gd/Sm site mixing. The findings could help coating designers choose rare-earth tantalate compositions with lower thermal conductivity.

With the continuous advancement of industrialization, high-precision actuators are increasingly being applied in fields requiring high accuracy, such as aerospace, smart vehicles, and robotics. However, the current mainstream actuator materials on the market are lead-containing ceramics primarily composed of lead zirconate titanate (PZT). During the manufacturing process, these ceramics produce lead and lead oxide, both of which are highly harmful to the environment and human health. Therefore, the development of lead-free ceramics capable of serving as high-precision actuator materials is urgently needed. As the most widely studied lead-free system, perovskites have rightfully become the most extensively investigated lead-free material family. Among them, barium titanate (BaTiO₃)-based lead-free ceramics, one of the most promising systems, have attracted widespread research due to their excellent stability and favorable electro-strain properties. However, although phase boundary engineering, the construction of polar nanoregions (PNRs), and defect engineering have partially improved the strain hysteresis of ceramic materials, these advances still fall short of meeting the demands of high-precision actuators.

Plastic waste should not be viewed as a uniform refuse stream, but as a heterogeneous carbon reservoir whose recycling pathway is dictated by polymer composition, contamination level and degradation history. Here, we outline a graded recycling framework that prioritizes carbon retention rather than technology-driven conversion. Clean and separable plastic streams should first undergo physical recycling to preserve polymer backbones and avoid unnecessary bond cleavage. Mixed, aged or contaminated fractions are better suited to selective chemical routes, including solvolysis, hydrogenolysis, catalytic depolymerization, electrified pyrolysis and gasification, which can reconstruct carbon into monomers, hydrocarbons, syngas or platform chemicals. Biological recycling is most effective for oxygenated intermediates generated through pretreatment. Integrating sorting, safety control and life-cycle assessment, this physical–chemical–biological hierarchy matches each plastic carbon stream with its most valuable and sustainable conversion pathway.