SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4310-4
Electrically actuated microrobots, typically defined as devices under 5 cm in length and 5 g in mass, offer distinct operational advantages over thermally, magnetically, or optically driven counterparts, particularly at the centimeter scale where external field-generation hardware imposes prohibitive cost and redundancy. This review systematically examines the intrinsic coupling mechanisms between the electromechanical performance parameters of functional materials and the resulting locomotion modes of microrobots. The central premise is that material-level electromechanical properties—actuation strain, blocking force, energy density, and drive voltage—directly govern critical system-level capabilities including obstacle-crossing ability and energy efficiency. The authors analyze how distinct material classes, such as dielectric elastomers, piezoelectric ceramics, and shape-memory alloys, map to specific locomotion modalities, thereby delineating the current performance boundaries of the field. The review identifies that power supply and control strategy remain the two dominant bottlenecks limiting autonomous operation and long-duration mission execution. By establishing a direct correlation between material selection and locomotion performance, this work provides a structured framework for researchers to set research directions and performance targets. The analysis concludes with a summary of challenges and future trends, emphasizing the need for materials that simultaneously satisfy low drive voltage, high strain, and high power density requirements for real-world deployment in unstructured environments.
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/s40843-025-3761-7
Ruthenium-based materials, including metallic Ru and RuO2, are promising electrocatalysts for electrochemical water splitting (EWS) due to their high activity for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). However, their practical application is hindered by the relatively strong adsorption of reaction intermediates on Ru surfaces and the oxidative dissolution of RuO2 under operating conditions. This review provides a comprehensive overview of recent progress and challenges in Ru-based electrocatalysts for EWS. We first summarize the fundamentals of EWS, including reaction mechanisms and activity descriptors. Then, we detail typical synthesis methods such as hydrothermal/solvothermal syntheses, organic ligand-assisted syntheses, pyrolysis, acid etching, cation exchange, and molten salt-assisted syntheses. Subsequently, we focus on enhancement strategies, including alloying, doping, structure design, interface engineering, single-atom catalyst design, high-entropy alloy design, phase engineering, and defect engineering, with typical examples illustrating structure-property correlations. Finally, we address remaining challenges and future prospects for the development of efficient and durable Ru-based electrocatalysts for sustainable hydrogen production.
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.
The Chinese Journal of Process Engineering•2026•DOI: 10.12034/j.issn.1009-606X.225222
The composite tridimensional rotational flow sieve tray (CTRST) integrates a packing zone and a swirl zone to enhance gas-liquid contact, yet its application range and structural optimization are hindered by unclear cross-zone flow distribution mechanisms. This study experimentally investigates gas-liquid cross-zone distribution and flow loss in both zones, introducing net cross-zone flow proportions for gas and liquid phases to quantify inter-zone flow. Under tested conditions, the net liquid cross-zone flow proportion ranged from -0.325 to -0.370, indicating net liquid flow from the swirl zone to the packing zone, while the net gas flow proportion ranged from 0.022 to 0.310, indicating net gas flow from the packing zone to the swirl zone. Analysis of loss flow ratios revealed that liquid spray density and gas kinetic energy factor had minor influence on net liquid loss flow proportion (always less than -0.037), suggesting low resistance to liquid exchange. Conversely, gas loss flow proportion varied significantly from -0.047 to -0.319, indicating substantial resistance to gas cross-zone interaction. This gas loss ratio initially increased then decreased with liquid spray density, peaking at 92.26 m3/(m2·h), and increased with gas kinetic energy factor. A predictive model for net cross-zone flow proportions was developed, correlating operational parameters with flow loss intensity, providing theoretical support for optimizing tray design and operation.
Environmental Chemistry•2026•DOI: 10.7524/j.issn.0254-6108.2025041502
Microplastics (MPs), defined as plastic particles smaller than 5 mm, are ubiquitous environmental contaminants with documented presence in urban, rural, marine, remote, and polar atmospheres. The atmosphere serves as a primary medium for their long-range transport, raising concerns regarding climate interactions and human health. This review synthesizes recent advances in atmospheric MPs research, encompassing sampling strategies, pretreatment protocols, analytical techniques, occurrence characteristics, and ecological ramifications. Passive and active sampling methods are delineated, with active samplers enabling quantitative flux measurements. Pretreatment typically involves sequential steps of sieving, density separation, digestion, staining, and filtration to isolate MPs from complex matrices. Identification relies on visual inspection, micro-Fourier transform infrared spectroscopy (μ-FTIR), micro-Raman spectroscopy, laser direct infrared imaging (LDIR), and mass spectrometry. Reported atmospheric MPs predominantly exhibit dimensions below 700 μm, with fibrous morphologies being most prevalent. Color distribution is dominated by black, followed by white and transparent particles. Over 20 polymer types have been identified, with textiles, tire wear, and dust identified as principal sources. Atmospheric MPs can influence solar radiation balance, cloud formation processes, and pose risks to flora, fauna, and human health. However, research remains nascent; standardization of sampling and analytical protocols, along with comprehensive toxicological assessments, are critical knowledge gaps requiring urgent attention.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4158-6
Near-infrared piezochromic materials exhibiting luminescence responses are critical for mechanical sensors and storage devices. Covalent organic frameworks (COFs), as crystalline porous materials, combine structural adaptability with tunable photophysical properties, yet their piezochromic applications remain underexplored. Here, we report a series of donor-acceptor structured two-dimensional COFs (2D COFs) with bright red emission, all showing pronounced red-shifts spanning red to near-infrared regions. Notably, Py-BO-COF exhibits the largest piezochromic shift of 187 nm with a high sensitivity of 44.52 nm GPa−1, significantly surpassing Py-BT-COF, TPE-BO-COF, and most reported COF/MOF systems. Py-BO-COF also demonstrates fully reversible and repeatable emission switching over multiple cycles, maintaining excellent linearity without degradation. In situ spectroscopic analyses and theoretical simulations reveal that variations in piezochromic rates arise from differences in charge-transfer (CT) processes, while the pronounced red-shift in Py-BO-COF is associated with reduced interlayer distance and enhanced coplanarity. This study systematically establishes the structure-property relationship in piezochromic 2D COFs, offering strategic guidance for designing highly sensitive and reversible pressure-responsive materials, thereby advancing smart piezochromic systems.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4116-0
The design of solid electrolyte interphases (SEIs) for poly(vinylidene fluoride)-based solid-state batteries has largely focused on solvent-affinity of Li+ to generate robust but ionically sluggish LiF-rich layers, inherently compromising transport kinetics. Here, we establish a paradigm based on quantifiable physicochemical descriptors (ionic potential and donor number) to guide the design of amphitropic ion pairs (AIPs). These AIPs are engineered to simultaneously tailor both the solvent-affinity and anion-affinity of Li+: a solvent-philic cation with high ionic potential (Al3+) first sequesters reactive solvents, clearing the path for a high-donor-number, lithium-philic anion (NO3−) to remodel solvation. This rationally guided, sequential mechanism enables the in situ synthesis of a LiF/Li3N heterostructured SEI, where dendrite-suppressing LiF domains are seamlessly integrated with ultra-fast Li3N ion channels. This design heterogeneity effectively enhances stability and kinetics, yielding a robust and highly conductive interface. Consequently, Li|Li cells achieve >2000 h of stable cycling, and Li|LiNi0.8Co0.1Mn0.1O2 full cells surpass 600 cycles.