SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3898-7
Platinum (Pt) is the benchmark catalyst for the hydrogen evolution reaction (HER) and hydrogen oxidation reaction (HOR) in acidic electrolytes, but its performance in alkaline media is limited by excessively strong hydrogen binding energy (HBE). Here, we report oxygen-modified ultrasmall RuCu nanocrystals (RuCu/C-200) as an efficient catalyst for both alkaline HER and HOR. The RuCu/C-200 catalyst exhibits excellent HER activity with an overpotential of 9 mV at 10 mA cm−2 and a Tafel slope of 19.7 mV dec−1. For HOR, it achieves a 4.2-fold higher exchange current density than the unannealed sample. Mechanistic studies reveal that the optimized HBE, hydroxyl binding energy (OHBE), and strongly hydrogen-bonded interfacial water, induced by oxygen modification, are the intrinsic determinants of the improved catalytic activity. This work underscores the potential of combining nanoscale structural design with oxygen modification to develop high-performance Ru-based electrocatalysts for both alkaline HER and HOR.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202511076
This study investigated the altitudinal distribution and enrichment characteristics of heavy metals in the soil-plant system of the northern and southern mountains of Lhasa on the Tibetan Plateau. Soil and dominant plant samples were collected from three sites along an elevation gradient from 3,650 to 4,150 m, and concentrations of Cr, Cd, Cu, Zn, Ni, As, and Pb were analyzed. Soil heavy metal concentrations ranged from 0.06 to 184.4 mg·kg−1, with all elements except Cd and Pb exceeding local background values. Plant heavy metal concentrations were within normal ranges, indicating no obvious stress. Correlation analysis revealed significant positive correlations between soil Zn and Cd, Cr and Ni, and plant Zn and Cu. Except for Cr, Cu, and Cd, plant and soil concentrations of the same element were significantly correlated. Bioconcentration factor (BCF) analysis showed that most plants had weak enrichment capacity (BCF < 1), but five species, including Ephedra sinica and Rheum likiangense, exhibited BCF > 1 for Cd, with R. likiangense showing the highest BCF of 4.01. The enrichment capacity varied with altitude and species. Potential ecological risk assessment indicated that Cd posed a relatively high risk in plants, warranting attention. This study fills a gap in understanding the spatial distribution and enrichment of heavy metals in this region, providing a scientific basis for ecological management and environmental protection.