Huaijuan Zhou

The sustainable expansion of nuclear power hinges on securing uranium supply and managing radioactive wastewater, yet conventional recovery methods suffer from low capacity, poor selectivity, and sluggish kinetics. Piezocatalysis offers a promising alternative, but its efficacy in single‐phase materials is restricted by the piezoelectric screening effect. Herein, we construct a zinc oxide@zinc selenide (ZnO@ZnSe) heterojunction as a high‐performance piezocatalyst for ultrasound‐stimulated uranium recovery. A spontaneous interfacial built‐in electric field with a ZnO‐to‐ZnSe orientation is established at the heterojunction, which actively mitigates the potential screening effect and amplifies the piezoelectric polarization. Consequently, the optimized ZnO@ZnSe‐10 delivers an excellent uranium uptake capacity of 1372.7 mg·g ⁻¹ , high extraction selectivity, and good cycling stability. Mechanistic investigations elucidate a hydrogen peroxide (H ₂ O ₂ )‐mediated piezocatalytic cascade: piezoelectrons convert dissolved oxygen (O ₂ ) to superoxide radicals (•O ₂ ⁻ ), whose disproportionation generates in situ H ₂ O ₂ that oxidatively precipitates soluble hexavalent uranyl ions (UO ₂ ²⁺ ) as insoluble crystalline uranyl peroxide hydrates ((UO ₂ )O ₂ ·2H ₂ O and UO ₃ ·2H ₂ O). Density functional theory (DFT) calculations further confirm that the interfacial electric field lowers the thermodynamic barrier for key oxygen‐containing intermediates, thereby promoting sustained H ₂ O ₂ production for uranium recovery. This work establishes a general strategy to overcome the piezoelectric screening effect, providing a feasible strategy for high‐efficiency uranium extraction.

Efficient uranium recovery from wastewater is vital for nuclear fuel sustainability and environmental protection. However, conventional photocatalytic and adsorption approaches suffer from sluggish charge separation, limited active sites, and poor selectivity. Piezo‐photocatalysis, integrating light and mechanical stimuli, can address these issues by accelerating charge dynamics, which calls for piezo‐photocatalysts with tunable polarization and well‐defined crystal configurations. Herein, ternary Zn–In–S layered nanosheets (ZnIn ₂ S ₄ , Zn ₂ In ₂ S ₅ , and Zn ₃ In ₂ S ₆ ) with tunable metal‐layer stacking configurations are fabricated via chemical vapor transport (CVT). By adjusting the Zn/In stoichiometry, we precisely govern the stacking geometry and crystal symmetry, enabling programmable spontaneous polarization and piezo‐photocatalytic activity. Among them, Zn ₂ In ₂ S ₅ exhibits the strongest spontaneous polarization (ΔV = 3.44 eV, µ = 3.534 Debye), delivering the highest hydrogen peroxide (H ₂ O ₂ ) production rate (689 µmol·g ⁻¹ ·h ⁻¹ ) under combined ultrasonic and light irradiation. DFT reveals that Zn ₂ In ₂ S ₅ optimizes interfacial electron transfer to *O ₂ and *OOH intermediates and lowers the free‑energy barrier for the rate‑determining *OOH formation, rationalizing its superior two‑electron oxygen reduction activity. The in‑situ generated H ₂ O ₂ selectively precipitates uranyl ions (UO ₂ ²⁺ ) as metastudtite ((UO ₂ )O ₂ ·2H ₂ O), achieving an uptake capacity of 1709.3 mg·g ⁻¹ . Our findings unveil the intrinsic structure‐polarization‐catalysis correlation induced by crystal stacking and symmetry, establishing a paradigm for designing efficient piezo‐photocatalysts toward uranium recovery.

Piezoelectric materials for uranium extraction have attracted increasing attention, as they offer a self‐powered, light‐independent strategy to harness ambient mechanical energy. However, natural mechanical energies are typically weak and low‐frequency, necessitating materials with high flexibility, facile deformation, and large surface area. Herein, we demonstrate that the ABCABC stacking sequence along the c ‐axis in two‐dimensional (2D) 3R‐ zinc indium sulfide (3R‐ZnIn ₂ S ₄ ) nanosheets induces intrinsic non‐centrosymmetry, enabling robust piezocatalysis for on‐site hydrogen peroxide (H ₂ O ₂ ) generation and simultaneous uranium extraction. Density functional theory (DFT) calculations confirm that solvation effects enhance the lattice flexibility and intrinsic dipole moment of 3R‐ ZnIn ₂ S ₄ , resulting in the formation of an electron‐rich surface that thermodynamically favors the two‐electron oxygen reduction reaction (2e− ORR) for H ₂ O ₂ generation. Under mild ultrasonic agitation (35 kHz, 50 W), the 3R‐ZnIn ₂ S ₄ nanosheets achieved a H ₂ O ₂ yield of 276.7 µmol g ⁻¹ h ⁻¹ and a uranium extraction capacity of 763.2 mg g ⁻¹ . Mechanistic investigations elucidate that the uranium extraction process proceeds through a dual‐coordination pathway, integrating direct piezoelectric reduction and in situ H ₂ O ₂ ‐mediated complexation of uranium species. Notably, 3R‐ZnIn ₂ S ₄ demonstrates excellent cycling stability over five cycles, high selectivity toward uranium, and effective anti‐biofouling performance under ultrasonic conditions (35 kHz, 50 W). Collectively, our findings establish stacking‐induced piezoelectricity as a light‐independent strategy for sustainable uranium extraction to support nuclear energy development.

Indoor service robots often face challenges in target localization and robotic grasping under cluttered backgrounds, partial occlusion, and viewpoint variations. To address these issues, this study proposes a vision-guided robotic grasping framework based on an improved feature matching algorithm termed Mahalanobis-accelerated Scale-Invariant Feature Transform Plus (MSIFT+). The proposed method integrates Mahalanobis distance metric reconstruction with a dynamic Best-Bin-First (BBF) search strategy to improve matching robustness and computational efficiency. A multi-scenario indoor dataset was constructed to evaluate the proposed method under rotational variation, weak-texture, and partial occlusion conditions. The results demonstrate that the MSIFT+ algorithm significantly outperforms other methods in cross-scenario consistency and adaptability to weakly textured targets. Furthermore, a binocular vision-guided robotic grasping system was developed and validated through practical robotic experiments. Experimental results confirm that the MSIFT+ algorithm enhances detection performance for small and clustered targets in complex environments. The proposed framework provides an effective and reliable solution for robotic object localization and grasping in complex indoor environments.

Photocatalytic uranium extraction from wastewater is of great significance for environmental remediation and resource recycling, yet conventional photocatalysts for this purpose suffer from insufficient active sites and low carrier separation efficiency. To address these challenges, we report a rational strategy of constructing sulfur‐vacancy‐rich Lewis acid sites on two‐dimensional 3R‐phase ZnIn ₂ S ₄ nanosheets. The sulfur vacancies, acting as electron‐deficient centers, serve as robust Lewis acid sites that can preferentially adsorb uranyl ions. Meanwhile, the synergistic effect between the sulfur vacancies and the 3R‐phase crystal structure facilitates charge separation and transfer to drive uranyl photoreduction. This integrated strategy achieves a remarkable enhancement in uranium extraction capacity, increasing from 133 (bulk) to 1320 mg/g (sulfur‐vacancy‐rich nanosheets). Notably, the sample maintains outstanding selectivity for uranium even in the presence of multiple competing ions (each at 100 ppm, K ⁺ , Ca ²⁺ , Mg ²⁺ , Zn ²⁺ , Co ²⁺ , Ni ²⁺ , Pb ²⁺ , Cu ²⁺ , Fe ³⁺ , and V ⁵⁺ ). Furthermore, the material exhibits inherent anti‐biofouling performance (≈100% after 3 h) and excellent cycling stability over 10 cycles. Our findings reveal the dual role of sulfur vacancies in photocatalysis as a binding site for uranium and an electronic modulator for charge dynamics, thereby proposing a “phase‐defect synergy” design principle for the development of advanced environmental remediation materials.

Microplastics can traverse human physiological barriers, infiltrate and accumulate in critical organs and tissues (e.g., brain, blood, and heart) over extended periods, posing significant threats to human health. While microplastic degradation in aquatic environments (e.g., contaminated water) has been extensively studied, research on bloodstream microplastic degradation remains largely unexplored, leaving a critical gap in remediation strategies. To fill this gap, we pioneered the fabrication of biocompatible magnetically driven Fe ₃ O ₄ @polydopamine (PDA)-lipase microrobots by functionalizing Fe ₃ O ₄ nanoparticles with PDA and lipase for blood-borne microplastic degradation. In vitro blood experiments confirmed that this platform holds promise for future detoxification of circulating microplastics. The microrobots integrate synergistic functions: Fe ₃ O ₄ enables magnetic responsiveness for precise movement control; PDA provides adhesive properties for robust microplastic binding; and lipase mediates enzymatic microplastic degradation. Guided by an external rotating magnetic field, the microrobots achieve targeted microplastic capture and in situ enzymatic degradation in blood without releasing harmful substances, addressing a pivotal safety concern for biomedical applications. Performance evaluations showed ~25% microplastic degradation efficiency in blood after 7 days of incubation. Additionally, the microrobots can be effectively recycled via magnetic separation postdegradation, reducing residuals and improving practicality. Hemolysis assays using rabbit blood and toxicity evaluations using human umbilical vein endothelial cells and immunofluorescence experiments confirmed their excellent biocompatibility and immunogenicity, an indispensable prerequisite for potential in vivo translation. As a proof-of-concept study, this work provides a promising biocompatible approach for blood microplastic degradation and clearance, simultaneously overcoming the technical challenge of blood-specific targeted degradation and meeting safety requirements, thus laying a foundation for microrobot-based mitigation of microplastic health hazards.

Transition metal trichalcogenides (TMTCs) of Group IVB (e.g., ZrS₃) are promising lithium-ion battery (LIB) anodes owing to their tunable band gaps, anisotropic conductivity, and high specific capacities. Here, microsized ZrS₃ with a quasi-1D chain-based structure and van der Waals stacked layers were synthesized via a simple solid-state reaction. Subsequently, the ZrS₃ anode was evaluated across distinct voltage windows, the storage mechanism switched from intercalation (≥1.0 V) to conversion (down to 0.001 V). The ZrS₃ electrode delivers a high capacity of 844 mAh g^–1 at 50 mA g^–1 after 40 cycles, with excellent rate capability (281 mAh g^–1 at 3000 mA g^–1) and outstanding cycling stability, maintaining 408 mAh g^–1 over 2300 cycles at 3000 mA g^–1. Ex situ XRD/SEM-EDX/XPS track phase and surface evolution, while EIS resolves interfacial charge-transfer/ion-transport kinetics. DFT reveals low-barrier Li⁺ diffusion along interchain pathways in bulk (≈0.12 eV) and monolayer ZrS₃. A directional increase in the calculated Young’s modulus under small strain suggests robust mechanics upon cycling. These experimental–theoretical insights establish ZrS₃ as a low-potential, high-rate anode for lithium-ion batteries and clarify the intercalation–conversion crossover in Group IVB TMTCs.