SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4273-3
Freestanding membranes have driven a profound evolution of strain engineering by fundamentally overcoming the substrate clamping effect. This structural degree of freedom enables the introduction of spatially complex, reversible, and giant strain fields into the membranes via mechanical manipulations such as stretching, bending, and interfacial twisting, ultimately facilitating the modulation of diverse physical properties. This review systematically discusses recent experimental and theoretical advances in the field, highlighting the modulation of physical properties via uniaxial/biaxial strain, strain gradients, and oxide twist. These mechanical strain strategies substantially broaden the range of achievable material properties, furthermore provide fundamentally new pathways for realizing unconventional mechanical behaviors, inducing emergent polar topological structures, and exploring correlated electronic states. Finally, this review summarizes current methodologies for implementing emergent strain engineering of oxide membranes, delves into the profound impacts of spatially complex strain on the fundamental physical properties of freestanding oxides, and offers a forward-looking perspective on the tremendous opportunities and challenges in this rapidly evolving field.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3642-4
High-density glass scintillators are promising alternatives to crystals for next-generation radiation detection due to their low cost, excellent physical and chemical stability, and processability. In this study, a series of Ce3+-activated gadolinium gallium borosilicate (GGBS x) glasses were synthesized via vacuum melt-quenching. With increasing Gd2O3 content, glass density increased from 5.86 to 6.05 g/cm3, and molar volume from 36.43 to 39.79 cm3/mol. Extended X-ray absorption fine structure (EXAFS) analysis revealed that in GGBS 1 glass, Ce3+ exclusively adopts a hexahedral [CeO6] configuration, while Gd3+ exhibits both hexahedral and octahedral coordination with a bond length of 2.35±0.1 Å and Debye-Waller factor σ2 of 0.0122±0.0015 Å2. As Gd2O3 content increased, shallow trap depth rose from 0.804 to 0.858 eV, while deep trap depth first increased from 0.948 to 1.434 eV then decreased to 1.010 eV. GGBS 1 glass exhibited high transmittance (~80%) in the visible range and a photoluminescence quantum yield of 78.4%. Under X-ray irradiation, its X-ray excited luminescence intensity reached 128.5% of that of Bi4Ge3O12 (BGO) crystal, with a spatial resolution of 29.1 lp/mm, approaching the highest reported for glass scintillators. Under γ-ray excitation, it achieved a light yield of 1058 photons/MeV and an energy resolution of 23.7% at 662 keV. These results indicate that GGBS 1 glass scintillator warrants further development for applications in X-ray imaging and γ-ray spectroscopy.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3816-y
Tool protective films operate under extreme service conditions, requiring exceptional hardness. Transition metal diborides (TMB2), with strong covalent TM–B and B–B bonds, are promising candidates, but achieving superhardness while preserving their simple binary structure remains challenging. Here, we use HfB2 as a model system to reveal how boron vacancy filling and in-plane compressive stress synergistically enhance hardness, through combined experimental synthesis and first-principles calculations. (001)-oriented HfB2 thin films were fabricated, including sub-stoichiometric HfB2−x, stoichiometric HfB2, and stoichiometric HfB2 under compressive stress. Nanoindentation shows the hardness increases from 33.0 ± 1.1 GPa in HfB1.90 to 40.5 ± 0.4 GPa in stoichiometric HfB2, and further to 45.7 ± 1.1 GPa under −3.67 GPa stress. Calculations reveal that vacancy filling increases the number of load-bearing bonds and strengthens B–B bonding via charge accumulation, while compressive stress shortens B–B bonds to further enhance their strength. These findings clarify the atomic-scale mechanisms of vacancy and stress engineering in TMB2, and propose a simple, scalable pathway to superhard protective films without alloying or doping, addressing a long-standing challenge in coatings for extreme environments.
Journal of Fuel Chemistry and Technology•2026•DOI: 10.1016/S1872-5813(26)60649-4
To achieve efficient conversion of lignin-derived phenolic compounds into high-value hydrocarbon fuels, a series of NiCo bimetallic catalysts with N-doped biochar and Al2O3 composite supports (NiCo/NC-Al2O3) were designed and synthesized. Comprehensive characterizations (XRD, TEM, XPS, H2-TPD) revealed the superior catalytic activity in the hydrodeoxygenation (HDO) of lignin-derived phenolic compounds. The optimized Ni8Co2/NC-Al2O3 catalyst exhibited good metal dispersion and excellent hydrogen dissociation adsorption capacity. Under mild reaction conditions (240°C, 1 MPa H2, 4 h), it achieved complete conversion of guaiacol and 99.9% selectivity to cyclohexane, significantly outperforming monometallic Ni10/NC-Al2O3 and Co10/NC-Al2O3 catalysts. Comparative studies indicated a synergistic effect between Ni and Co, where the introduction of Co effectively promoted aromatic ring hydrogenation and C−O bond cleavage. The catalyst maintained high activity after four reuse cycles, demonstrating outstanding structural stability. This study elucidates the regulatory mechanism of the Ni-Co synergistic effect on catalytic performance, providing new insights for the development of efficient non-noble metal HDO catalysts.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202608026
Biochar and microbial inoculants are widely used for agricultural soil amendment. To investigate the effects of different straw biochars and Bacillus subtilis inoculant, applied individually or combined, on nitrogen transformation in dryland soil, a 60-day laboratory incubation experiment was conducted with six treatments: control (CK), 4% rice straw biochar (S), 4% rapeseed straw biochar (Y), 4% rice straw biochar plus 5 mg/kg inoculant (SJ), 4% rapeseed straw biochar plus 5 mg/kg inoculant (YJ), and inoculant alone (J). Results showed that rice straw biochar significantly increased soil nitrate nitrogen content by 148.74%–152.68% compared to CK, enhancing nitrification. Combined application with inoculant further increased average net nitrogen mineralization rate by 77.28%–99.38%. Conversely, rapeseed straw biochar decreased nitrate nitrogen by 51.66%–57.61%, and combined application reduced net nitrogen mineralization rate by 82.07%–84.73%. Treatments S, Y, SJ, and YJ promoted microbial biomass nitrogen (MBN) synthesis, with S and Y increasing MBN by 2.02- and 2.20-fold over CK, respectively. Combined treatments further increased MBN by 103.26%–149.44% relative to single biochar treatments. These findings indicate that biochar type governs nitrification and net nitrogen mineralization, while combined application exerts synergistic effects on MBN. For comprehensive dryland soil improvement, YJ treatment is optimal, reducing inorganic nitrogen loss risk and enhancing microbial nitrogen activity.