SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-026-4309-8
Iridium-doped cobalt oxide nanosheets derived from a ZIF template were evaluated as oxygen evolution reaction (OER) catalysts for proton exchange membrane water electrolysis (PEMWE). Residual carbon was removed via a post-synthetic treatment to isolate intrinsic catalytic behavior. The Ir0.23Co0.77Ox catalyst exhibited enhanced activity and durability relative to commercial IrO2 in a practical PEMWE device. Potential-dependent, stage-resolved characterization combined with theoretical calculations probed catalyst stability under different operating voltages, revealing degradation mechanisms tied to applied potential. Contact angle measurements showed that the Ir0.23Co0.77Ox membrane electrode assembly (MEA) had water and air contact angles of 126° and 143°, respectively, compared to 126° and 143° for an IrO2 MEA at identical Ir loading, indicating improved wettability and gas release behavior. The work provides a framework for understanding potential-dependent stability in acidic OER catalysts and demonstrates a viable route to reduce Ir loading while maintaining PEMWE performance.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3887-6
The proliferation of 5G/6G communications and radar systems has intensified electromagnetic wave (EMW) leakage, interference, and thermal management challenges. This study presents a 3D MXene sponge/NiFe@NC heterostructure with tunable pore architecture, fabricated by pyrolyzing a polyurethane (PU) foam template uniformly coated with NiFe-decorated Ti3C2Tx MXene nanosheets. The resulting porous dielectric-magnetic network integrates interconnected MXene pathways with uniformly dispersed NiFe@NC nanoparticles, enabling synergistic dielectric-magnetic loss via conduction loss, dipole/interface polarization, and magnetic loss. Precise pore structure design enhances impedance matching and promotes multi-scattering and internal reflection of EMWs. An 'EMW-pore matching' mechanism is proposed, where pore size governs impedance matching at specific frequencies, enabling tunable absorption performance. The optimized absorber achieves a reflection loss (RL) of -67.84 dB, while radar cross-section (RCS) simulations confirm exceptional attenuation and stealth potential. Additionally, the 3D skeleton derived from PU foam confers remarkable thermal resistance and flame retardancy. This pore-regulation strategy provides a scalable route to designing lightweight, broadband, and thermally stable EMW absorbers for next-generation communication and stealth applications.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202506020
The rotary kiln roasting of lepidolite for lithium extraction faces challenges of unstable lithium conversion rates and high energy consumption. To address this, a multi-objective optimization method coupling improved neural network simulation with a multi-objective genetic algorithm was proposed, targeting the synergistic optimization of lithium conversion rate (TRLi) and natural gas consumption intensity (EIng). Using long-term industrial time-series data of batching parameters and kiln operating variables, back-propagation (BP) neural network and its particle swarm optimization (PSO) improved variant were developed to model TRLi and EIng. The PSO-BP model demonstrated superior accuracy in capturing the complex nonlinear relationships, reducing mean absolute percentage errors (MAPE) to 0.278 and 0.284 for TRLi and EIng, respectively. Subsequently, the non-dominated sorting genetic algorithm II (NSGA-II) was employed to construct a multi-objective optimization model, yielding a Pareto-optimal set of process parameters that maximize TRLi and minimize EIng. The results revealed that under NSGA-II optimized conditions, TRLi could be stabilized between 82.45% and 87.96%, an average increase of 3.61 percentage points over baseline operations, while EIng could be reduced to 53.7 m3 per ton of clinker. For an annual processing capacity of 3.2×105 tons of lepidolite concentrate and sulfate mixture, this corresponds to an additional 127.1 tons of lithium metal recovery, a reduction of 1,964,912 m3 in natural gas consumption, and a decrease of 3,763.84 tons in CO2 emissions annually. This study provides theoretical and technical support for the green, high-quality, and low-carbon supply of critical raw materials for the lithium battery new energy industry.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-3646-1
Repairing cartilage defects requires biomaterials with mechanical properties similar to native cartilage. However, balancing these properties with biodegradability remains a major challenge. In this study, a degradable antibacterial hydrogel with promising mechanical characteristics was developed for personalized cartilage defect repair. The hydrogel was synthesized using chitosan and gelatin via microcrystallization and gelation, combined with chemical crosslinking facilitated by epichlorohydrin. This method significantly enhanced the mechanical properties of the material, with compressive modulus of the optimal group reaching 0.2 MPa and tensile strength reaching 2.2 MPa, which are comparable to those of human cartilage. The hydrogel maintained its integrity after 50000 compression cycles. With excellent flowability prior to crosslinking, it can adapt to complex cartilage defects. The inclusion of gentamicin provides antibacterial properties, while nano-hydroxyapatite promotes osteogenesis. This hydrogel, with its multiple crosslinking mechanisms, balances mechanical strength, biodegradability, and adaptability, offering a promising solution for repairing infected cartilage defects.
SCIENCE CHINA Materials•2026•DOI: 10.1007/s40843-025-4107-x
Aqueous fiber zinc-iodine batteries (FZIBs) with four-electron redox exhibit inherent safety and high energy density for wearable electronics. Nevertheless, their practical implementations are hindered by unsatisfactory cycling stability and low realistic energy density, mainly caused by severe H2O-induced nucleophilic attack toward iodine species and poor zinc anode reversibility. Here, we report a quaternary ammonium-mediated coordination strategy to simultaneously address the irreversible cathode/anode redox behavior and thus promote the electrochemical performance of four-electron FZIBs. The cationic choline ion (Ch+) induces complexation with ICl2− via electrostatic interaction, homogenizing the electron cloud density and suppressing irreversible hydrolysis of I+ species, enabling a reversible near-theoretical high capacity of 418.3 mAh g−1. Meanwhile, preferentially adsorbed Ch+ on the zinc anode surface creates positively charged shielding layers, mitigating the tip effect caused by localized electric field and achieving robust zinc stripping/plating. The enhanced cathode/anode reversibility and improved interfacial stability enable stable FZIBs operation for over 20,000 cycles at 20.0 A g−1. Moreover, successful integration of FZIBs into electronic textiles with glucose and cardiac rhythm sensors demonstrates great potential for next-generation wearable electronics.