Latest ArticlesPancreatic cancer (PCa) is highly aggressive and resistant to conventional therapies due to its dense stroma and immunosuppressive microenvironment. To overcome these barriers, we engineered dextran-coated copper peroxide-doxorubicin nanoclusters (DCPD NCs) that enabled ultrasound (US)-augmented chemodynamic therapy (CDT) and chemotherapy. In the acidic tumor microenvironment, DCPD NCs disassemble and co-release Cu2+, doxorubicin, and self-supplied H2O2. Cu2+ depletes glutathione (GSH) and catalyzes H2O2 to generate •OH with US (1.5 fold higher than that without US). Under US treatment, DCPD NCs not only increased the permeability of Panc02 tumor spheroids, but also increased intracellular reactive oxygen species by 2.1 times, depleted GSH by up to 25.2%, and induced lipid peroxidation. This nanoplatform works synergistically to induce potent immunogenic cell death. In both subcutaneous and orthotopic PCa mice models, this nanoplatform demonstrated remarkable therapeutic effects. The tumor weights of mice treated with DCPD NCs + US were significantly reduced by 91.8% and 85.7% vs. controls, with robust calreticulin (CRT) exposure and HMGB1 translocation in tumors. This work establishes an US augmented and self-reinforcing nanoplatform that overcomes stromal and metabolic barriers in PCa, providing a synergistic strategy for catalytic immunotherapy.
Seawater electrolysis, utilizing coastal resources, holds great promise as a sustainable method for hydrogen production. However, the efficiency of seawater electrolysis is limited by anode catalysts with high overpotentials (η) and short lifespans, due to chloride-induced side reactions. In this study, we introduce sodium alginate (SA) modified NiFe layered double hydroxide nanosheets on Ni foam (SA@NiFe LDH/NF) as a highly efficient and stable electrocatalyst for long-term alkaline seawater oxidation. Our SA@NiFe LDH/NF needs a low η of 362 mV to reach 1000 mA/cm2, outperforming the unmodified NiFe LDH/NF (425 mV). Furthermore, it maintains continuous electrolysis for 1600 h at current densities of 500 and 1000 mA/cm2. In situ Raman spectroscopy reveals that the SA protective layer not only facilitates NiOOH formation but also establishes a dense electrostatic network via carboxyl groups, which repels chloride ions and ensures stable seawater oxidation. This work presents a promising strategy for developing durable, high-performance anodes and highlights the potential of natural polysaccharide coatings for enhancing anode corrosion resistance during the seawater electrolysis process.
Lithium-sulfurized polyacrylonitrile (Li-SPAN) batteries have attracted attention as a unique subset of lithium-sulfur batteries owing to their effectiveness in mitigating the shuttle effect caused by the dissolution of polysulfides. However, traditional SPAN electrodes typically exhibit an active material loading capacity of < 40 wt% and demonstrate suboptimal reaction kinetics, which limits their actual performance. In this study, a composite film (CoS2/FeS2@SeSPAN/CNTs) was developed, which is poised to serve as the cathode in commercial Li-SPAN batteries. The film was fabricated by forming a PAN framework through casting, subsequently growing Fe-ZIF-67 on it via hydrothermal processing, and converting it into CoS2/FeS2 heterostructure and SeSPAN through heat treatment. The porous structure of this material provided numerous sites for active material storage. This effect led to an active material loading capacity of 61 wt%. Experimental results and density functional theory simulations indicated that, owing to the shielding effect of the cathode solid electrolyte interface, the additionally stored active material exhibited an extended all-solid-state reaction mechanism. Furthermore, the internal electric field generated by the CoS2/FeS2 heterostructure effectively enhanced the adsorption and catalytic conversion of solid polysulfides, thereby improving lithium-ion migration efficiency. As a result, the active material stored in dual-mode exhibited high utilization rates. At a current density of 1 C, the capacity retention of the CoS2/FeS2@SeSPAN/CNTs cathode was 97.9% after 800 cycles. This result demonstrated that the design and development of the CoS2/FeS2@SeSPAN/CNTs composite film significantly enhanced the electrochemical performance of Li-SPAN batteries while paving the way for the commercial exploration of other heterostructural materials in energy storage systems.
O3-layered oxides are considered promising for various applications due to their high capacity. However, these O3-type materials are prone to undergo an irreversible O3-P3 phase transition, which adversely impacts their structural stability. Elemental doping has been identified as an effective strategy to mitigate this issue. However, substituting Cu at the redox center reduces the capacity of the pristine material. The unique introduction of the Sb element reduces the lattice oxygen ratio, leading to a significant increase in initial capacity. Thus, the Cu/Sb co-doped material NaNi0.37Mn0.49Cu0.13Sb0.01O2 (NNMCS) with unique O3-dominated phase transition process, was successfully prepared using the high temperature solid-phase method. Cu/Sb doping increases Mn4+ concentration through the charge compensation mechanism at transition metal sites, mitigating the negative structural effects of the dual simplicial state eg orbitals in the high-spin Mn3+ state. Doping with Cu/Sb increases the electron cloud density at the transition metal sites, enhancing the electron shielding effect and ultimately causing the distance between the transition metal sites to expand. The increased distance between the transition metal sites indirectly promotes flexibility during transition metal migration, resulting in electrode materials with a smaller rate of lattice parameter change during cycling and ultimately enhancing phase transition reversibility. As a result, NNMCS demonstrates a high initial specific capacity of 188 mAh/g and 78% capacity retention after 200 cycles at 1 C within a 2.0–4.3 V window. This work provides valuable insights into the coupling mechanism between capacity and structural stability in layered oxides for sodium-ion batteries.
The under-barrier Raman relaxation process has long presented a formidable challenge in advancing the performance of single-molecule magnets (SMMs). Exploring the nuanced differences in Raman relaxation processes between two structurally analogous systems remains relatively uncharted territory. Herein, two Dy(Ⅲ)-based single-ion magnets (SIMs) with pentagonal bipyramidal geometry were reported, and their Raman relaxation behaviors were regulated by precisely adjusting the protonation level of the bis-hydrazone moiety. Intriguingly, under the optimal magnetic field, the degree of protonation shows no impact on the Raman exponent n but causes a distinct variation in the Raman relaxation coefficient C. The effects of deprotonation on the molecular geometry and charge distribution were elucidated through ab initio and electrostatic potential (ESP) calculations. Deprotonation results in an asymmetric charge distribution within the equatorial plane, causing the coefficient C to increase substantially by 3.5 times, aligning closely with the theoretical calculation value of approximately 2.8 times. This study provides concise and effective molecular archetypes for investigating the Raman relaxation process.
Decorating semiconductor metal oxides (SMOs) with noble metals particles has been proved to be effective method to enhance their gas-sensing performance. However, the issue of noble metal particles aggregation might affect the sensitivity and stability of the material. Herein, a strategy is proposed for the construction of noble metals particles decorated SMOs featuring optimized gas sensing performance through the derivation of metal-organic frameworks (MOFs). By utilizing Sn/Zn-ZIF-8 framework as precursor to encapsulate Pt nanoparticles (NPs) followed by calcination, a core-shell structure of SnO2-ZnO encapsulated with Pt NPs (Pt@SnO2-ZnO) was successfully constructed. The Sn/Zn-ZIF-8 framework structure prevents the aggregation of Pt NPs, which facilitates the adsorption and dissociation of oxygen and methanol molecules. Thereby the Pt@SnO2-ZnO based gas sensor exhibited significantly enhanced response (73.6) towards 10 ppm methanol at 320 ℃ and exceptionally low theoretical detection limit (0.18 ppb), providing an effective approach for the modification of SMOs-based gas-sensing materials.
The development of electrode materials with a rapid diffusion kinetics and low polarization is crucial for improving energy storage in magnesium ion batteries (MIBs). Herein, the magnesium tungstate with thermal stability and good chemical stability is proposed as the electrode material in MIBs for the first time. According to the simulated results of density functional theory (DFT) calculations, the high exposed (001) plane of MgWO4 can be achieved as the preferred orientation for Mg2+ fast insertion/extraction. The MgWO4 microflowers with exposed (001) plane architecting by uniform nanosheets were successfully synthesized through a high-efficient microwave radiation strategy. The synthesis mechanism of MgWO4 microflowers was explored as "self-assembly-dissolution-recrystallization-Ostwald ripening" through the evolutions of the morphology and microstructure under continuous reaction timespan. As a MIB electrode material, the MgWO4 microflowers exhibit a good reversible specific capacity (54.6 mAh/g) and cycling stability (70.9% capacity retention after 100 cycles). In conclusion, the MgWO4 material with exposed (001) facet and layered pore structure effectively overcomes the slow diffusion kinetics in MIBs, presenting a new avenue for the design and synthesis of novel reversible electrode materials of MIBs.
Zeolite-like metal–organic frameworks (ZMOFs) are a unique branch of MOFs, compared to MOFs, the design and synthesis of ZMOFs is challenging due to the peculiar T-O-T angle. Herein, the first ZMOF with unique two-fold interpenetrated SOD topology, [(CH3)2NH2][Zn(2,5-ABTC)0.5(TAZ)]·DMF ·H2O (JLU-MOF119, 2,5-H4ABTC = 2,2′,5,5′-azobenzene tetracarboxylic, TAZ = 1H-tetraazol, DMF = N,N-dimethylformamide), was successfully constructed by utilizing a novel 4 + 4 + 2 strategy. In such a structure, the 4-connected 2,5-H4ABTC ligand serves as the 4-membered ring (4MR) of the structural building units, and the TAZ linker coordinates with the Zn2+ center to form a 6-membered ring (6MR), which assembles with the tetrahedral building units (TBU) to construct the SOD topology. Notably, the stretched and distorted 4MR, which gives rise to two distinct 6MR and a twisted framework, finally leads to the formation of a unique 2-fold interpenetrated SOD framework. The pore structure of JLU-MOF119 is featured by the ultra-microporous pore and the polar surface of the SOD cages caused by uncoordinated N and O sites coming from 2,5-H4ABTC and TAZ ligands, resulting in one-step C2H4 purification from C2H2/CO2/C2H4 mixtures. The dynamic breakthrough and recycling experiments confirm that the C2H4 purity is high up to 99.2%. The successful construction of JLU-MOF119 in this work breaks the theory of forbidden interpenetration in ZMOFs, which will provide more possibilities for structural design and the construction of more complicated structures.
The CO2 electroreduction is a valuable technology towards carbon neutrality but facing great challenge in fabricating efficient and stable electrode. Here we propose the construction of self-supported nanoarray electrode of ultrathin carbon-coated Bi nanospheres through a self-assembly and Joule heating method for high-efficiency electrocatalytic CO2 reduction. The electrode combines the advantages of facilitating electron transfer, accelerating the subsequent electro-proton coupling step in CO2 reduction process and protecting Bi nanoparticles from aggregation or electrochemical corrosion. The highest Faraday efficiency for formic acid in a solid-state electrolyte cell reaches 95.46% with a partial current density of 119.10 mA/cm2 and remains above 90% for 110 h. This route for assembling self-supported nanoarray electrode is rapid, facile, and can be employed in the large-scale fabrication of industrial electrodes in the future.