SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3293-7
Electrochemical CO2 reduction (CO2RR) to formate offers a sustainable route to value-added chemicals, but metal sulfide catalysts suffer from sulfur loss via spontaneous metal reduction, degrading performance. This study synthesizes three highly crystalline tin sulfides—SnS, Sn2S3, and SnS2—via solid-state reaction to probe the role of Sn–S bond strength distribution in CO2RR. SnS, with weaker Sn–S bonds, undergoes nearly complete reduction to metallic Sn, yielding a maximum formate Faradaic efficiency (FE) of 89.1% and partial current density of 138.2 mA cm−2. Sn2S3, possessing mixed bond strengths, experiences accelerative reduction initiated by cleavage of the weakest Sn–S bonds, resulting in inferior FE (73.5%) and current density (73.5 mA cm−2). In contrast, SnS2 with strong and uniformly distributed Sn–S bonds exhibits enhanced compositional stability, generating abundant Sn/SnS2 heterointerfaces that serve as favorable active sites. Consequently, SnS2 achieves a peak formate FE of 93.8% ± 0.59% at −1.0 VRHE and a partial current density of 195.3 mA cm−2 at −1.2 VRHE, surpassing both SnS and Sn2S3. This work establishes a direct correlation between Sn–S bond strength uniformity and catalytic durability, providing a design principle for stabilizing metal sulfide electrocatalysts against sulfur leaching in CO2-to-formate conversion.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3354-3
Nanocrystallization of glasses is a critical pathway for designing advanced materials with superior properties. This study investigates the crystallization behavior of lunar glasses retrieved by the Chang’E-5 mission. Solar wind irradiation induces abundant Fe nano-clusters (~2 nm) within a ~4 μm surface layer. Upon heating, these defects act as nucleation sites, facilitating homogeneous and dense Fe nanocrystals. In contrast, the unirradiated interior crystallizes into coarse Fe crystals. Inspired by these findings, advanced magnetic nanocrystalline alloys are designed based on Fe86B14 metallic glass via H+ ion irradiation. After H+ irradiation and nanocrystallization, the surface nanocrystals are 5–8 nm, significantly smaller than the deep interior (15–20 nm). Permeability at 10 kHz increases by ~10.2%. These results provide insights into the thermal stability of lunar glasses and present a novel strategy for designing advanced soft magnetic materials with enhanced performance.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3500-x
Cation vacancies were engineered into diamond-like (DL) chalcogenides to amplify tetrahedral distortion and second harmonic generation (SHG). Substitution of Ge4+ by P5+ in Cd4GeS6 yielded the defective DL phase Cd3.5PS6, which exhibits intrinsic Cd2+ vacancies and an 8.5-fold increase in [CdS4] tetrahedral distortion relative to Cd4GeS6. Consequently, Cd3.5PS6 achieves a 2 × AgGaS2 (AGS) SHG response at 2050 nm and a laser-induced damage threshold (LIDT) of 9.4 × AGS. Further equivalent substitution of Hg2+ concentrates Cd2+ vacancies at the Cd(2) site, producing Hg0.5Cd3PS6 with a 2.66-fold enhancement in [CdS4] distortion over Cd3.5PS6. This material delivers a 2.73 × AGS SHG response at 2050 nm, an LIDT of 5 × AGS, and a birefringence of 0.076 at 2050 nm. The results establish cation vacancies and mixed-atom radius scaling as effective levers for designing high-performance mid-infrared nonlinear optical crystals, circumventing the low LIDT of AgGaS2 and two-photon absorption of ZnGeP2.
SCIENCE CHINA Materials•2025•DOI: 10.1007/s40843-025-3751-6
Ionogels, which integrate the flexibility and ionic conductivity of ionic liquids with the mechanical robustness of polymer networks, have emerged as pivotal materials for flexible electronics. Their tissue-like biomechanical characteristics enable applications in health monitoring, smart wearables, and human-machine interfaces. However, ionogels are susceptible to mechanical damage under large deformations and continuous loading, leading to structural failure and device degradation. Self-healing capability, imparted through dynamic non-covalent bonds (hydrogen bonds, ionic interactions) and reversible covalent bonds, can significantly enhance device reliability, service life, and safety. This review systematically examines the latest progress in self-healing ionogels (SHIGs), covering self-healing mechanisms, design strategies, and preparation methods. Key applications are analyzed, including wearable strain sensors, flexible triboelectric nanogenerators, supercapacitors, flexible displays, and soft robots. The review highlights recent breakthroughs, such as rapid self-healing (within minutes) and superior toughness (fracture energy exceeding 10 kJ m⁻²) in ionically crosslinked polymer ionogels, and record-breaking mechanical properties in room-temperature self-healing ionogels inspired by sea cucumber dermis. Despite these advances, challenges persist in balancing self-healing efficiency with mechanical strength, achieving cost-effective scalability, and ensuring long-term stability under extreme conditions. Perspectives on future development are provided, emphasizing the need for multifunctional integration and standardized testing protocols to accelerate the commercialization of self-healing ionogels in next-generation flexible electronics.