The highly immunosuppressive tumor microenvironment (TME) restricts the efficient activation of immune responses. To restore the surveillance of the immune system for robust activation, vast efforts are devoted to normalizing the TME. Here, a manganese-doped layered double hydroxide (Mn-LDH) is developed for potent anti-tumor immunity by reversing TME. Mn-LDH is synthesized via a one-step hydrothermal method. In addition to the inherent proton neutralization capacity of LDH, the introduction of manganese oxide endows LDH with an additional ability to produce oxygen. Mn-LDH effectively releases Mn2+ and Mg2+ upon exposure to TME with high levels of H+ and H2O2, which activates synthase-stimulator of interferon genes pathway and maintains the cytotoxicity of CD8+ T cells respectively, achieving a cascade-like role in innate and adaptive immunity. The locally administered Mn-LDH facilitated a \"hot\" network consisting of mature dendritic cells, M1-phenotype macrophages, as well as cytotoxic and helper T cells, significantly inhibiting the growth of primary and distal tumors. Moreover, the photothermal conversion capacity of Mn-LDH sparks more robust therapeutic effects in large established tumor models with a single administration and irradiation. Overall, this study guides the rational design of TME-modulating immunotherapeutics for robust immune activation, providing a clinical candidate for next-generation cancer immunotherapy.

The present work describes a quick, simple, and efficient method based on the use of layered double hydroxides (LDH) coupled to dispersive solid phase micro-extraction (DSPME) to remove α-naphthol (α-NAP) and β-naphthol (β-NAP) isomers from water samples. Three different LDHs (MgAl-LDH, NiAl-LDH, and CoAl-LDH) were used to study how the interlayer anion and molar ratio affected the removal performance. The critical factors in the DSPME procedure (pH, LDH amount, contact time) were optimized by the univariate method under the optimal conditions: pH, 4-8; LDH amount, 5 mg; and contact time, 2.5 min. The method can be successfully applied in real sample waters, removing NAP isomers even in ultra-trace concentrations. The large volume sample stacking (LVSS-CE) technique provides limits of detections (LODs) of 5.52 µg/L and 6.36 µg/L for α-naphthol and β-naphthol, respectively. The methodology\'s precision was evaluated on intra- and inter-day repeatability, with %RSD less than 10% in all cases. The MgAl/Cl--LDH selectivity was tested in the presence of phenol and bisphenol A, with a removal rate of >92.80%. The elution tests suggest that the LDH MgAl/Cl--LDH could be suitable for pre-concentration of α-naphthol and β-naphthol in future works.

The development of nanomaterials for energy storage and conversion has always been important. Layered double hydroxide (LDH) is a promising material due to its high capacity, tunable composition and easy synthesis. In this work, the morphology of NiCo-LDH is tuned with surfactants including sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB), and investigated the correlation between morphology and electrochemical properties. NiCo-LDH-SDS with a layered structure exhibited a specific capacitance of 1004 C g-1 at 1 A g-1, which is higher than that of the needle-like NiCo-LDH-CTAB (678 C g-1) and the rod-like NiCo-LDH (279 C g-1). Meanwhile, NiCo-LDH-SDS and NiCo-LDH-CTAB showed a reduction of 36 and 19 mV, respectively, in their overpotentials at 10 mA cm-2 compared to NiCo-LDH. Contact angle and adhesive force measurements proved the influence of morphology on the interfacial properties that layered structure is favorable for the timely detachment of the bubbles. Therefore, rational morphology regulation of LDH can effectively alter the gas-liquid-solid interface and thereby accelerate the reaction kinetics. The connections between morphologies, bubbles releasing and electrochemical performance are well established in this work, which can be applied in the investigation of nanomaterials for energy-related activities, especially the ones concerning bubbles releasing processes.

Anionic redox allows the direct formation of O─O bonds from lattice oxygens and provides higher catalytic in the oxygen evolution reaction (OER) than does the conventional metal ion mechanism. While previous theories have predicted and experiments have suggested the possible O─O bond, it has not yet been directly observed in the OER process. In this study, operando soft X-ray absorption spectroscopy (sXAS) at the O K-edge and the operando Raman spectra is performed on layered double CoFe hydroxides (LDHs) after intercalation with [Cr(C2O4)3]3-, and revealed a three-step oxidation process, staring from Co2+ to Co3+, further to Co4+ (3d6L), and ultimately leading to the formation of O─O bonds and O2 evolution above a threshold voltage (1.4 V). In contrast, a gradual oxidation of Fe is observed in CoFe LDHs. The OER activity exhibits a significant enhancement, with the overpotential decreasing from 300 to 248 mV at 10 mA cm-2, following the intercalation of [Cr(C2O4)3]3- into CoFe LDHs, underscoring a crucial role of anionic redox in facilitating water splitting.

This study presents a promising method for creating high-performance supercapacitor electrodes. The approach involves crafting a unique composite material-nickel-cobalt-layered double hydroxides (NiCo-LDH) grown on carbon nanoballs (CNBs). This is achieved by first creating a special carbon material rich in oxygen and nitrogen from a polybenzoxazine source. At first, eugenol, ethylene diamine and paraformaldehyde undergo Mannich condensation to form the benzoxazine monomer, which undergoes self-polymerization in the presence of heat to produce polybenzoxazine. This was then carbonized and activated to produce CNBs containing heteroatoms. Then, through a hydrothermal technique, NiCo-LDH nanocages are directly deposited onto the CNBs, eliminating the need for complicated templates. The amount of CNBs used plays a crucial role in performance. By optimizing the CNB content to 50%, a remarkable specific capacitance of 1220 F g-1 was achieved, along with excellent rate capability and impressive cycling stability, retaining 86% of its capacitance after 5000 cycles. Furthermore, this NiCo-LDH/CNB composite, when combined with active carbon in a supercapacitor configuration, delivered outstanding overall performance. The exceptional properties of this composite, combined with its simple and scalable synthesis process, position it as a strong contender for next-generation sustainable energy storage devices. The ease of fabrication also opens doors for its practical application in advancing energy storage technologies.

Indomethacin (INDO) has a mechanism of action based on inhibiting fatty acids cyclooxygenase activity within the inflammation process. The action mechanism could be correlated with possible anticancer activity, but its high toxicity in normal tissues has made therapy difficult. By the coprecipitation method, the drug carried in a layered double hydroxides (LDH) hybrid matrix would reduce its undesired effects by promoting chemotherapeutic redirection. Therefore, different samples containing INDO intercalated in LDH were synthesized at temperatures of 50, 70, and 90 °C and synthesis times of 8, 16, 24, and 48 h, seeking the best structural organization. X-ray diffraction (XRD), vibrational Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), spectrophotometric analysis in UV-VIS, and differential thermogravimetric analysis (TGA/DTA) were used for characterization. Our results indicate that higher temperatures and longer synthesis time through coprecipitation reduce the possibility of INDO intercalation. However, it was possible to establish a time of 16 h and a temperature of 50 °C as the best conditions for intercalation. In vitro results confirmed the cell viability potential and anticancer activity in the LDH-INDO sample (16 h and 50 °C) for gastric cancer (AGP01, ACP02, and ACP03), breast cancer (MDA-MB-231 and MCF-7), melanoma (SK-MEL-19), lung fibroblast (MRC-5), and non-neoplastic gastric tissue (MN01) by MTT assay. Cell proliferation was inhibited, demonstrating higher and lower toxicity against MDA-MB-231 and SK-MEL-19. Thus, a clinical redirection of INDO is suggested as an integral and adjunctive anticancer medication in chemotherapy treatment.

Metal-based catalytic materials exhibit exceptional properties in degrading emerging pollutants within Fenton-like systems. However, the potential risk of metal leaching has become pressing environmental concern. This study addressed scientific issues pertaining to the leaching behavior and control strategies for metal-based catalytic materials. Innovative cobalt-aluminum hydrotalcite (CoAl-LDH) triggered peroxymonosulfate (PMS) activation system was constructed and achieved near-complete removal of Ciprofloxacin (CIP) across diverse water quality environments. Notably, it was found that the tunable ion exchange and Al3+ stabilization of CoAl-LDH occurred due to the particularity of neutral water quality, resulting in significantly lower Co2+ leaching levels (0.321 mg/L) compared to acidic conditions (5.103 mg/L). In light of this, machine learning technology was then employed for the first time to simulate the dynamic trend of Co2+ leaching and elucidated the critical regulatory roles and mechanisms of Al3+, aqueous matrix, and reaction rate. Furthermore, degradation systems based on different water quality and metal leaching levels regulated the generation levels of SO4.- and O2∙-, and the unique advantages of free radical attack paths were clarified through CIP degradation products and ecotoxicity analysis. These findings introduced novel insights and approaches for engineering application and pollution control in metal-based Fenton-like water treatment.

The main challenges faced by aqueous rechargeable nickel-zinc batteries are their comparatively low energy density and poor cycling stability. Moreover, the preparation procedures of these cathodes are complex and not easily scalable. Herein, we utilized MXene to improve the electrodeposition preparation of NiCo layered double hydroxides (LDH). Benefiting from the improved interfacial contact between nickel foam (NF) and platting solution and the enhanced ionic conductivity of platting product based on MXene additives, the resulting binder-free NiCo LDH electrode can achieve ultrahigh areal loading (~65 mg cm-2) with abundant active surface for redox reactions and maintained short transport pathway for ion diffusion and charge transfer. Furthermore, the as-fabricated alkaline NiCo LDH-based battery delivers high discharge capacity, up to 20.2 mAh cm-2 (311 mAh g-1), accompanied by remarkable rate performance (9.6 mAh cm-2 or 148 mAh g-1 at 120 mA cm-2). Due to the high structural and chemical stability of MXenes/LDH-based electrode, excellent cycling life can also be achieved with 88.6% capacity retention after 10000 cycles. In addition, ultrahigh areal energy density (31.2 mWh cm-2) and gravimetric energy density (465 Wh kg-1) can be simultaneously achieved. This work has inspired the design of advanced cathode materials to develop high-performance aqueous zinc batteries.

The application of single-atom catalysts (SACs) to advanced oxidation processes (AOPs) based on peroxymonosulfate (PMS) has attracted considerable attention. However, the catalytic pathways and mechanisms underlying these processes remain unclear. In this study, NiFe-LDH was synthesized and single Ru atoms were stably loaded onto it by forming Ru-O-M (M=Ni or Fe) bonds (Ru@NiFe-LDH). This was demonstrated using high-angle annular dark-field scanning TEM (HAADF-STEM) and X-ray absorption fine structure spectra (XANES). The Ru@NiFe-LDH/PMS system showed a high catalytic reactivity (100 % sulfamethoxazole degradation in only 30 min), high stability (97 % reactivity was maintained after continuous operation for 400 min), and wide pH suitability (working pH range 3-11) for AOPs. The crucial roles of the high-valent species (Ru(V) = O) and 1O2 in this reaction were verified. Density functional theory (DFT) calculations revealed that electron transfer produced a positively charged Ru. This enhances the adsorption of negatively charged PMS anions onto the Ru monoatomic sites, thereby, causing the formation of Ru-PMS* complexes. This study implies that the structure-function relationship between organic compounds and SACs plays a significant role in PMS-based AOPs, and provides a comprehensive mechanism for the role of high-valent species in heterogeneous Fenton-like systems.

The super-stable mineralization of metal ions from industrial wastewater by in situ synthesis of layered double hydroxides (LDHs) has been regarded as a sustainable approach from environmental protection and resource utilization perspectives. Herein, the study reports a super-stable mineralization of metal ions including Ni, Fe, Cr, Mn, Cu, Ca, Al, etc. from smelting wastewater by in situ synthesis of NiFe-based LDHs through facile coprecipitation. Such approach exhibits superior mineralization efficiency of metal ions simultaneously that can remove hundreds, thousands, or even tens of thousands mg/L of multiple metal ions to below the values of the Chinese National Emission Standards of Pollutants. Furthermore, the obtained NiFe-based LDHs exhibit excellent catalytic performance of phenol hydroxylation due to the mineralization of multiple metals on the laminates, where 48.24% conversion of phenol and 71.58% selectivity of dihydroxybenzenes are realized under room temperature for 3 h. This work paves a sustainable strategy for hazardous material disposal and resource utilization.