SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4417-x
Balancing mechanical strength, corrosion resistance, and soft magnetic performance in structural-functional integrated materials remains a persistent metallurgical challenge. This study reports a face-centered cubic (FCC) Fe40Co35Ni15Al3Ta2Cr5 (at.%) high-entropy alloy (HEA) that achieves an unprecedented combination of these properties. The alloy exhibits a tensile strength of ~1200 MPa, total elongation of ~25%, saturation magnetization of 101.54 Am2·kg-1, and coercivity of 267.34 A·m-1. These values surpass most reported magnetic HEAs and conventional soft magnetic alloys. In a simulated 3.50 wt.% NaCl seawater environment, the alloy demonstrates a corrosion current density of 3.99 × 10-7 A·cm-2, comparable to 316L stainless steel. The synergy arises from nanoprecipitate engineering within the FCC matrix, which impedes dislocation motion while maintaining magnetic domain wall mobility and promoting a protective passive film. This work provides a design pathway for soft magnetic structural-functional materials suitable for corrosive marine environments, where simultaneous load-bearing and magnetic actuation are required.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4488-x
Thermochromic smart windows based on hydrogels suffer from inevitable freezing at subzero temperatures and dehydration at elevated temperatures, severely limiting their year-round applicability. This study reports a hydrogel-derived liquid (HDL) smart window that circumvents these limitations through a solvent-exchange strategy. The HDL is synthesized by polymerizing a hydroxypropyl cellulose (HPC) and N-isopropylacrylamide (NIPAM) network in a water-glycerol binary solvent, followed by complete removal of the water phase via vacuum-assisted evaporation. The resulting anhydrous liquid exhibits a lower critical solution temperature (LCST) of 32 °C, with a solar modulation ability (ΔTsol) of 63.2% and a luminous transmittance (Tlum) of 88.1% in the clear state. Critically, the HDL remains optically switchable after 1000 hours at -40 °C and 1000 hours at 80 °C, with no observable phase separation or freezing. The smart window prototype demonstrates a 12.3% reduction in indoor cooling energy consumption in a simulated tropical climate and a 9.8% reduction in heating energy in a cold climate, compared to a commercial low-E glass. The liquid-state formulation enables facile large-area fabrication via roll-to-roll processing, with a demonstrated 30 cm × 30 cm prototype retaining 95% of the initial ΔTsol after 500 bending cycles. This work establishes a viable pathway for all-climate energy-efficient building envelopes.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4302-9
The pre-deposited lead iodide (PbI2) film in two-step inverted perovskite solar cells (PSCs) often exhibits a dense structure, which impedes the diffusion and reaction of organic ammonium salts, leading to unreacted PbI2 residues and compromised device performance. To address this, 2,4-oxazolidinedione (OD) is introduced as a molecule additive into the PbI2 precursor solution. Owing to its stronger coordination with PbI2, OD effectively modulates its crystallization behavior, resulting in a porous structure. This porous structure significantly facilitates the diffusion and infiltration of organic ammonium salts, thereby minimizing PbI2 residue and enhancing the completeness of the perovskite conversion. Furthermore, OD and the constructed porous network jointly retard the crystallization kinetics of perovskite, promoting the formation of perovskite films with improved crystallinity and preferred crystal orientation. Therefore, the optimized PSCs achieve a power conversion efficiency (PCE) of 26.31%, and demonstrate excellent operational stability, retaining 90.24% of initial PCE for 1500 h at 25°C and 90.47% after 1000 h at 65°C. The champion device exhibits a VOC of 1.197 V, a JSC of 26.28 mA cm-2, and an FF of 83.58%, with negligible hysteresis. This study presents a straightforward yet effective approach to advancing the performance and stability of inverted PSCs fabricated via the two-step method.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4233-8
Ferroelectrics with intrinsic electric polarization are indispensable for non-volatile storage and computing-in-memory chips. However, conventional perovskite ferroelectrics suffer from size effects that degrade functional properties at reduced dimensions, limiting nanoscale applications. Fluorite-based ferroelectrics, such as HfO2 and ZrO2, maintain ferroelectricity in nanocrystalline films and are compatible with Si-based processes, but their ferroelectricity relies on a metastable orthorhombic (O) phase that is thermodynamically unstable at room temperature, leading to wake-up effects, fatigue, and reduced reliability. Previous stabilization strategies (stress, doping, oxygen vacancies) lack atomic-level verification or depend on specific processing conditions. This highlight discusses a recent Nature Materials study by Wang et al. that demonstrates grain boundary (GB) chemical engineering as a new paradigm. Using a La0.67Sr0.33MnO3 (LSMO) buffer layer, they achieved stable O-phase ZrO2 films. Atomic-scale HAADF and EELS revealed ordered GBs with selective segregation of La, Sr, and Mn, forming chemically ordered heterostructures. First-principles calculations showed that the ordered eg/t2g orbital arrangement of Mn3+/Mn4+ at GBs softens phonon modes by regulating Zr–O bond strength, stabilizing the ferroelectric phase. This work establishes GBs as independent functional units, offering a universal approach for designing highly stable metastable functional materials.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202507054
In many Chinese wastewater treatment plants (WWTPs), residual chlorine is still manually monitored at low frequencies, leading to imprecise disinfectant dosing. This study systematically compared four machine learning models—backpropagation (BP) neural network, long short-term memory (LSTM) neural network, random forest (RF), and support vector regression (SVR)—for predicting chlorine consumption (i.e., the difference between chlorine dose and residual chlorine) during non-monitoring periods under different residual chlorine monitoring frequencies (every 1, 2, 4, 6, and 8 h). Using data from Plant A (equipped with online residual chlorine monitoring) and Plants B and C (manual monitoring every 6 h and 8 h, respectively), input variables included online water quality indicators (temperature, flow, NH3-N, CODCr, TP, TN) and chlorine dose. Results showed that at 1-h intervals, LSTM achieved the highest prediction accuracy; at 2–4-h intervals, RF performed best; at 6-h or lower frequencies, BP was superior; SVR performed worst across all frequencies. Validation on Plants B and C confirmed BP's optimal performance under low-frequency conditions, and particle swarm optimization (PSO) significantly improved its accuracy. These findings provide a basis for selecting appropriate machine learning models for chlorine consumption prediction under varying monitoring frequencies, particularly low-frequency manual monitoring, thereby supporting precise disinfectant dosing control.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4144-y
Developing efficient strategies for electrically manipulating two-dimensional magnetism at room temperature is a key challenge in contemporary spintronics. In this study, we demonstrate giant electromechanical control over the magnetism of the room-temperature van der Waals ferromagnet Fe3GaTe2 by integrating it with the ferroelectric α-In2Se3. Modest gate voltages lead to an almost complete suppression of the coercive field by 96.5%, corresponding to a remarkable peak modulation sensitivity of ~8.1 mT V−1, which stands out among existing van der Waals magnetoelectric systems. Importantly, this substantial magnetoelectric response is predominantly unaffected by voltage polarity, as both positive and negative gate voltages induce similar magnetic modulation effects. To elucidate the underlying mechanism, we tracked the voltage-induced Raman spectral changes, revealing a peak shift of 1.7 cm−1 that accurately represents an effective in-plane tensile strain of ~1.42% under an equivalent bias, demonstrating polarity independence as well. The synchronized magnetic response and strain variation unequivocally indicate that the induced tensile strain serves as the fundamental physical driver behind the magnetic modulation. Additionally, density functional theory calculations corroborate that the reduction in magnetic anisotropy induced by tensile strain results in a decrease in the coercive field. Our work establishes a novel and efficient approach for achieving voltage control of magnetism at room temperature in van der Waals multiferroic heterostructures, highlighting their significant potential for applications in ultra-low-power magnetic logic and sensing technologies.