SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4245-4
The discrimination of volatile organic compounds (VOCs) at trace concentrations remains a critical challenge for environmental monitoring, industrial process control, and non-invasive disease diagnostics. Conventional electronic noses rely on sensor arrays comprising multiple chemically distinct receptors, which introduces fabrication complexity, calibration drift, and cross-sensitivity. Here, we demonstrate that a single-component Ti3C2Tx MXene (TM) sensor array, engineered through controlled surface chemistry and device architecture, generates independent and high-dimensional characteristics (IHC) sufficient for precise VOC pattern recognition. By exploiting the intrinsic heterogeneity of TM basal planes and edge sites, we achieve differential interaction motifs without expanding elemental composition. The array discriminates VOCs including acetone, ethanol, toluene, and hexane at concentrations down to 100 ppb with classification accuracy exceeding 95%. Principal component analysis reveals distinct clustering with cumulative variance of 92.3% captured by the first three principal components. The sensor exhibits a limit of detection of 50 ppb for acetone and response/recovery times of 12 s and 18 s, respectively. Long-term stability tests over 30 days show less than 5% signal degradation. This single-component strategy simplifies fabrication, reduces calibration overhead, and offers a scalable pathway for miniaturized, low-power VOC sensing platforms compatible with Internet of Things (IoT) deployment.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4303-7
Sodium-ion batteries (SIBs) are promising for grid-scale storage and low-speed electric vehicles, yet their electrochemical behavior is governed by intricate mechanical-electrochemical coupling effects, rendering failure mechanisms not fully understood. Here, we develop an in-situ pressure-electrochemical monitoring system and reveal the failure mechanism of commercial Ah-level NaNi1/3Fe1/3Mn1/3O2//hard carbon (NNFMO//HC) sodium-ion pouch cells. Under an initial external pressure of 500 kPa, the full cell retains 90.07% of its capacity after 500 cycles at 0.5 C. Operating at the optimal pressure of 500 kPa effectively avoids heterogeneous sodium deposition in HC anodes, suppresses gas evolution from electrolyte decomposition, and prevents irreversible phase transitions in NNFMO cathodes during long-term cycling, thereby mitigating capacity degradation. Deviation from this optimal pressure leads to spatially non-uniform sodium deposition, accelerated electrolyte decomposition, and irreversible cathode phase transitions, collectively accelerating capacity fade. This work establishes a quantitative relationship between external pressure and pouch cell degradation, advancing SIBs development and application.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4250-0
Shape memory polymer (SMP)-based transfer printing offers a promising route for heterogeneous integration of flexible electronics, yet non-contact release reliability remains a critical bottleneck. This study systematically investigates the influence of pickup heating modes—localized versus global—on the release yield and energy-delivery mechanisms through combined experiments and finite element simulations. The localized heating mode concentrates strain energy at the interface, enabling controlled chip ejection with high yield, whereas global heating dissipates energy, leading to release failure. Quantitative analysis reveals that localized heating achieves a release yield of 100% under optimized conditions, compared to near-zero for global heating. The ejection velocity under localized heating is higher, which may induce chip bouncing on the receiver substrate, affecting transfer accuracy; however, this can be mitigated by adjusting release gap and laser parameters. The findings establish a theoretical framework for energy pathway design, providing guidelines for achieving high-yield, accurate non-contact release in laser-induced transfer printing. This work advances the practical application of SMP-based transfer printing for micro-LED displays and flexible electronics, addressing a key manufacturing bottleneck.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4262-7
The escalating demands of artificial intelligence, machine learning, and neural computing necessitate multifunctional optoelectronic devices capable of integrating sensing, memory, and processing. Two-dimensional van der Waals heterostructures (vdWHs) offer unique advantages, yet their practical deployment is hindered by complex architectures and inefficient mode-switching. Here, we demonstrate a MoTe2/SnS2 anti-ambipolar heterojunction device enabling single-gate reconfiguration among frequency doubling, broadband photodetection, and neuromorphic computing. The device exhibits a peak-to-valley ratio (PVR) of 465, ensuring efficient frequency doubling. As a photodetector, it operates across an exceptionally broad spectral range of 520–2200 nm, with outstanding responsivity and detectivity. Furthermore, the device emulates complete synaptic behaviors, including short-term plasticity (STP), long-term plasticity (LTP), and paired-pulse facilitation (PPF). Integrated into a reservoir computing (RC) system trained on a vehicle motion dataset, it achieves a directional recognition accuracy of 98.7%. This work establishes a paradigm for multifunctional integration and low-power neuromorphic computing, advancing next-generation intelligent optoelectronic systems.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3744-9
The high-value utilization of industrial wastes is critically important for environmental protection and sustainable development. In this work, amorphous NaFeP2O7 (NFPO) and NaFeP2O7/rGO (NFPO/rGO) composite are synthesized via a selective chemical precipitation approach, utilizing industrial jarosite residue as the iron source. The sodium storage performance and mechanism of this amorphous NFPO/rGO composite as a novel cathode material for sodium-ion batteries (SIBs) are explored for the first time. The as-synthesized amorphous NFPO/rGO composite exhibits outstanding long-term cycling performance of 79.1 mAh g−1 after 1000 cycles at 0.1 A g−1, while the crystalline NFPO/rGO composite does not work. Galvanostatic intermittent titration technique and in-situ electrochemical impedance spectroscopy analysis demonstrate that the amorphous NFPO/rGO composite has high Na+ diffusivity and fast kinetics. In-situ X-ray diffraction analysis reveals the structure change from amorphous NaFeP2O7 to triclinic Na2FeP2O7 during the first discharge process and then evolves to a highly disordered structure in the subsequent charge/discharge cycles. The present work not only provides an avenue for the high-value utilization of jarosite residue but also offers theoretical guidance for the structural design and development of NaFeP2O7-based cathode materials for SIBs.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3603-2
Conventional glass fiber/epoxy (GF/EP) composites, while structurally competent, are hindered by poor interlaminar toughness, low thermal conductivity, and electromagnetic transparency. This study transforms GF/EP composites into advanced structural multifunctional materials by embedding Ti3C2Tx MXene/poly(acrylic acid) (PAA) aerogels (TPA) as integral interlayers. Hybrid composites with tailored architectures—aligned (GFAM_A) and random (GFAM_R) TPA/GF/EP laminates—were fabricated via unidirectional and isotropic freeze-casting, respectively. The integrated aerogel phase promotes crack deflection and distributed energy dissipation, leading to notable enhancements in interlaminar shear strength (ILSS) and fracture toughness. The continuous Ti3C2Tx MXene network within the aerogel creates efficient through-thickness thermal conduction pathways and imparts strong microwave absorption properties. Notably, GFAM_A achieves simultaneous increases of approximately 52% in ILSS, 78% in toughness, and 42% in thermal conductivity, along with effective microwave absorption: a minimum reflection loss of −23.47 dB and a maximum effective bandwidth of 2.70 GHz. This study demonstrates that precision aerogel engineering provides a powerful strategy for upgrading conventional glass fiber composites into advanced multifunctional structural materials.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3654-5
Hydrogen production by photosynthetic green algae is an efficient biological process that utilizes light energy to convert water and carbon dioxide into clean and renewable energy. In this paper, we constructed a hybrid system combining graphitic carbon nitride (g-C3N4) and Chlorella pyrenoidosa (Chlorella), in which g-C3N4 serves as an extracellular electron source and Chlorella acts as a biological reactor for specific hydrogen production. In particular, the electronic structure of carbon nitride was optimized by means of hydrothermal alkalization and copper ion doping, expanded the light absorption range and enhanced the light response ability. g-C3N4, as an extracellular electron source, can provide electrons for Chlorella to improve hydrogen production performance which is 3.7 times that of bare Chlorella. The construction of a biological hybrid system is a feasible optimization strategy for the hybrid system to promote the synergistic effect of the hybrid system by regulating the properties of non-living components.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3633-5
High-temperature interfacial diffusion in Half-Heusler (HH) thermoelectric devices poses significant challenges for practical applications, particularly the diffusion of Ag from conventional solders, which degrades material performance and device stability. This study reveals anomalous Ag diffusion through a Cr powder barrier layer into Ti0.5Zr0.5NiSn0.98Sb0.02, driven by Sn phase penetration. In contrast, employing a Cr foil barrier layer pre-densified the material, effectively preventing Sn phase penetration and eliminating Ag diffusion pathways, thereby preserving junction integrity. After aging at 973 K for 30 days, the Cr foil junction maintained a clean interface with a low contact resistivity of 0.27 μΩ cm2. Benefiting from this interfacial design, a Hf-free HH module achieved a high conversion efficiency of 10.4% at a hot-side temperature of 976 K, alongside long-term stability. This work addresses critical bottlenecks in developing high-performance, low-cost HH modules, facilitating their commercial application in waste heat recovery.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202605023
Identifying the characteristics of carbon emissions and driving forces of the railway sector is essential for formulating effective measures to develop a green and low-carbon railway industry. This study systematically evaluated the direct and indirect carbon emissions from 2016 to 2021 generated by the railway sector of China, and analyzed the spatiotemporal dynamic changes of the carbon emissions. On this basis, by adopting the LMDI model, the key factors affecting the carbon emissions of railway sector were discerned. Moreover, the variations in the dominant factors of the carbon emissions over time, and the spatial heterogeneities in the dominant factors of the carbon emissions of the 18 railway bureaus, were analyzed. The results show that: 1) During the periods from 2016 to 2021, the carbon emissions of China's railway sector showed an overall upward trend, increasing from 57.7486 million tons to 64.2084 million tons, by 11.2%. The Shanghai Bureau, Beijing Bureau, Zhengzhou Bureau, Chengdu Bureau and Guangzhou Bureau substantially contributed to the increases of railway carbon emissions. In spatial, the carbon emissions of the 18 railway bureaus were characterized by lower emissions in the west and higher emissions in the east, mainly due to the regional differences in the socio-economic development, industrial structure and population density; 2) During 2016 to 2021, the decline in energy consumption intensity reduced the carbon emissions of the railway sector by 18.8654 million tons, while the changes in carbon emission intensity, economic benefits of per unit passenger and freight turnover, and operating capacity led to an increase of a sum of 25.3252 million tons of carbon emissions. When decomposing the contributions of each factor by sub-periods, it can be found that the impacts of these factors on the carbon emissions changed over time. Only the factor of carbon emission intensity showed a promoting effect in all sub-periods, the other three factors, as energy consumption intensity, economic benefits of per unit passenger and freight turnover, and operating capacity, had a conversion between promoting and inhibiting effects. 3) The dominant factors of carbon emissions across the 18 railway bureaus exhibited spatial heterogeneity. For instance, operating capacity was the main promoting factor for bureaus like Taiyuan, Beijing, Lanzhou, Nanning, Hohhot, Urumqi, and Qinghai-Tibet, while energy consumption intensity was the main inhibiting factor. For Shanghai, Kunming, Wuhan, Chengdu, Xi'an, Zhengzhou, Jinan, Shenyang, Nanchang, and Guangzhou, economic benefits per unit turnover was the main promoting factor, with energy consumption intensity as the main inhibiting factor. For Harbin, energy consumption intensity was the main promoting factor, while economic benefits per unit turnover was the main inhibiting factor. 4) The railway sector can reduce carbon emissions by optimizing transport organization to reduce empty car rates, optimizing energy structure, and retrofitting infrastructure for energy efficiency, while implementing differentiated emission reduction strategies tailored to each bureau's characteristics.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4045-x
The release of radioactive iodine from nuclear accidents and nuclear medicine poses significant environmental and health risks. Here, we report the design and synthesis of two cross-linked macrocycle-based porous organic polymers (P1 and P2) with different functionalities for efficient and rapid capture of radioactive iodine. P1 achieves complete iodine adsorption within 5 minutes, with an exceptional adsorption rate constant (k_obs) of 18.92 g g−1 min−1 (8.24 g g−1 min−1 for P2), representing a record-high iodine removal rate among state-of-the-art porous organic polymers. P1 demonstrates superior iodine adsorption efficacy in dynamic flow-through experiments, achieving a remarkable efficiency of 96.4% for radioactive 131I removal, greatly minimizing radiation contamination. Experimental and modelling techniques reveal that the superior iodine adsorption performance originates from electron-rich functional groups, hydrophobic surface, and porous structure of P1, thus exhibiting remarkable iodine capture capabilities through charge transfer, halogen bonding, and hydrophobic effects. The adsorbents show excellent stability and performance under complex and harsh conditions (pH 2–10) and can be easily regenerated, confirming their excellent reusability and potential for practical applications.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3430-0
Electrocatalytic nitrate reduction to ammonia (NO3RR) offers a sustainable alternative to the Haber-Bosch process but is limited by insufficient atomic hydrogen (H*) supply and sluggish hydrogenation of oxynitride intermediates. This study constructs a NiCo-LDH/Cu2O heterojunction catalyst via a facile hydrothermal method, leveraging the strong nitrate adsorption of Cu2O and interfacial coupling with NiCo layered double hydroxides. By tuning the Ni/Co ratio, proton absorption behavior is modulated, achieving an ammonia yield of 0.382 mmol h−1 cm−2 and a Faraday efficiency of 80.4% at −0.3 V vs. RHE. Experimental results demonstrate that interfacial coupling induces optimal electronic effects, enhancing adsorption and activation of reaction intermediates, optimizing the reaction pathway, and suppressing the competing hydrogen evolution reaction. The NiCo-LDH/Cu2O system prevents nitrite accumulation and addresses the poor conductivity of LDH and low electron transfer rates. This work provides a feasible strategy for designing efficient, cost-effective NO3RR catalysts for sustainable ammonia synthesis.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3460-4
Atomically dispersed single-atom catalysts (SACs) on graphene offer a tunable platform for electrochemical CO2 reduction to CH4, yet the mechanistic coupling between active-site identity and coordination environment remains poorly resolved. This study constructs a structure-activity map for 110 stable SACs with MXnY4−n motifs (X, Y = N, S, P; M = 19 transition metals) using density functional theory and multi-task symbolic regression. The binding strength of the *OCHO intermediate (ΔE*OCHO) is identified as the initial activity descriptor, correlating with the onset potential for CH4. A three-dimensional descriptor comprising valence-electron number and electronegativity of metal and coordinating atoms reproduces ΔE*OCHO and onset potential variations without further DFT calculations. The analysis reveals that coordination environments modulate the d-band center and charge transfer, shifting the rate-determining step from CO2 activation to *CO hydrogenation. This descriptor enables rapid screening of SACs, bypassing computationally expensive DFT workflows. The findings provide a rational basis for designing graphene-supported SACs with enhanced CH4 selectivity and establish a generalizable framework for decoupling active-site and coordination effects in CO2 electrocatalysis.