Qi Liu

Aqueous zinc batteries are promising for safe and durable energy storage, but sluggish Zn²⁺ transport and unstable Zn interfaces limit their cycling performance. Reducing the water content of hydrogel electrolytes can mitigate parasitic reactions, yet preserving ionic conduction remains challenging. Here, we report a water-lean double-network gel electrolyte (DNGE) formed by in situ polymerization of acrylamide within a bacterial cellulose (BC) scaffold in ZnSO₄ solution. The resulting BC/polyacrylamide (PAM) architecture combines a water content of 20.5 wt% with an ionic conductivity of 11.72 mS cm⁻¹. Electrochemical measurements and characterization of cycled electrodes indicate reduced polarization, more uniform Zn deposition and less accumulation of crystalline byproducts. With DNGE, Zn||Zn symmetric cells sustain plating and stripping for ~1300 h at 0.5 mA cm⁻² and 0.5 mAh cm⁻². Zn|I₂ full cells deliver ~150 mAh g⁻¹ after 7580 cycles at 10 C. The corresponding pouch cells deliver 169 mAh g⁻¹ after 100 cycles and power a toy car. The BC/PAM architecture therefore enables reduced water content while preserving efficient ion transport and stable Zn electrochemistry.

Two‐dimensional (2D) perovskites are promising candidates for solar cells. However, the processing strategies that promote large, oriented grains often concurrently induce tensile strain and microcracks, creating a critical growth‐strain trade‐off. Herein, we propose a surface self‐templated dual‐anion synergy by partially substituting iodide with low amounts of thiocyanate and chloride (2 mol%) in 2D (AA) ₂ (MA) ₃ Pb ₄ I ₁₃ perovskites ( n = 4), in which SCN anion spontaneously enriches at the top surface as a structure‐directing template that drives oriented grain growth but inevitably introduces tensile strain, and Cl anion concurrently segregates to the top surface as a strain buffer that alleviates this strain without sacrificing grain size. Systematic in situ and depth‐resolved analysis reveals that such synergy effectively navigates the growth‐strain trade‐off of 2D perovskites, yielding enlarged grains, strong vertical orientation, and a crack‐free morphology, which contributes to the suppression of non‐radiative recombination and the enhancement of charge transport in solar cells. As a result, the champion device with dual‐anion engineering achieves a remarkable efficiency of 19.11%, and retains over 95% of its initial efficiency after 1800 h under one‐sun irradiation. This work establishes a fundamental understanding of the growth‐strain dilemma in 2D perovskites, providing a universal design principle for high‐efficiency 2D perovskite solar cells.

Constructing heterojunction interfaces has emerged as an effective strategy for enhancing photocatalytic performance. Herein, a MoO3-x@CuIn5S8 (MO@CIS) core-shell heterostructure was rationally designed and successfully synthesized. The localized surface plasmon resonance (LSPR) effect of MoO3-x enhanced visible-light absorption and promoted the generation of photogenerated charge carriers. The direct Z-scheme heterojunction facilitated efficient charge separation, while the interfacial Mo-S bonds provided rapid pathways for charge transfer. Owing to these synergistic effects, the optimized MO@CIS photocatalyst exhibited CO and CH4 evolution rates of 5.25 and 62.21 μmol·g-1·h-1, accompanied by an excellent CH4 selectivity of 92.2%.

MXenes, with a high surface area, abundant active sites, and excellent ion transport properties, have demonstrated excellent electrochemical performance. However, systematic comparisons of the structural evolution process and electrochemical performance for MXene are lacking. In this study, multilayer MXene (M-Ti₃C₂T_x) was successfully fabricated by in situ etching. During the subsequent centrifugation process, the thicker and heavier multilayer sheets settled due to their faster sedimentation rate, while the lighter, surface-functionalized monolayer sheets remained colloidally stable in the supernatant due to solvation and electrostatic repulsion, thereby achieving separation and obtaining delaminated MXene (D-Ti₃C₂T_x). Structural analysis indicates that the removal of the aluminum layer synergizes with the exfoliation of the nanosheets, significantly increasing the interlayer spacing and making the sheet structure more pronounced, and the pore structure is more abundant. Especially, in three-electrode and two-electrode systems at an identical mass loading of 5 mg on carbon paper, D-Ti₃C₂T_x delivered a higher specific capacitance, more pronounced pseudocapacitive behavior, and a superior rate capability compared to Ti₃AlC₂ and M-Ti₃C₂T_x. Such excellent electrochemical performance of D-Ti₃C₂T_x is due to the shortened ion diffusion path in the delaminated structure, which enables rapid ion migration, an extremely large specific surface area, and a mesoporous structure that provides abundant active sites. This study underscores the significant potential of D-Ti₃C₂T_x in emerging energy storage systems and offers insights into guiding MAX phase synthesis during its preparation.

High-conductivity AlSi8-based alloys designed for electrical interconnection and thermal management have been increasingly applied in the communication and new-energy vehicle sectors, particularly in key components such as 5G base-station housings and battery enclosures. However, under industrial mass-production conditions, the mechanisms by which complex interactions among trace impurity elements affect electrical conductivity and mechanical properties remain insufficiently understood, which still limits batch-to-batch stability. The main challenges are as follows. First, owing to Sr modification and aging-induced precipitation, the microstructure of AlSi8 alloys exhibits a multiphase, multiscale coupled feature characterized by micron-scale irregular eutectic constituents together with nanoscale precipitates. Conventional strengthening models based on empirical formulations are therefore unable to quantify the contribution of microstructural evolution to the mechanical response. Second, quantitative prediction models for electrical conductivity under the coexistence of multiple impurity elements remain unexplored. In this work, based on samples collected from an industrial die-casting production line, machine learning was combined with in-situ synchrotron X-ray characterization to systematically establish the full composition-microstructure-property relationship linking alloy composition, microstructure, electrical conductivity, and mechanical behavior. A quantitative conductivity-prediction model and a multiscale strengthening framework were developed. By incorporating thermodynamic descriptors derived from Pandat calculations, including solid solubility and phase volume fraction, an interpretable machine-learning model for electrical conductivity prediction was established. In addition, in-situ synchrotron X-ray experiments under quasi-static tensile loading were used to obtain the evolution of lattice strain and dislocation density for different grain families in the constituent phases, from which the load-bearing stresses of the individual phases were determined.