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Autophagy could play suppressing role in cancer therapy by facilitating release of tumor antigens from dying cells and inducing immunogenic cell death (ICD). Therefore, discovery and rational design of more effective inducers of cytotoxic autophagy is expected to develop new strategies for finding innovative drugs for precise and successful cancer treatment. Herein, we develop MoO3‐x nanowires (MoO3‐x NWs) with high oxygen vacancy and strong photothermal responsivity to ablate tumors through hyperthermia, thus promote the induction of cytotoxic autophagy and severe ICD. As expected, the combination of MoO3‐x NWs and photothermal therapy (PTT) effectively induces autophagy to promote the release of tumor antigens from the ablated cells, and induces the maturation and antigen presentation of dendritic cells (DCs), subsequently activates cytotoxic T lymphocytes (CTLs)‐mediated adaptive immunity. Furthermore, the combination treatment of MoO3‐x NWs with immune checkpoint blockade of PD‐1 could promote the tumor‐associated macrophages (TAMs) polarization into tumor‐killing M1 macrophages, inhibit infiltration of Treg cells at tumor sites, and alleviate immunosuppression in the tumor microenvironment, finally intensify the anti‐tumor activity in vivo. This study provides a strategy and preliminary elucidation of the mechanism of using MoO3‐x nanowires with high oxygen vacancy to induce autophagy and thus enhance photothermal immunotherapy. [ABSTRACT FROM AUTHOR]

Zinc‐air batteries (ZABs) have attracted considerable attention for their high energy density, safety, low noise, and eco‐friendliness. However, the capacity of mechanically rechargeable ZABs was limited by the cumbersome procedure for replacing the zinc anode, while electrically rechargeable ZABs suffer from issues including low depth of discharge, zinc dendrite and dead zinc formation, and sluggish oxygen evolution reaction, etc. To address these issues, we report a hybrid redox‐mediated zinc‐air fuel cell (HRM‐ZAFC) utilizing 7,8‐dihydroxyphenazine‐2‐sulfonic acid (DHPS) as the anolyte redox mediator, which shifts the zinc oxidation reaction from the electrode surface to a separate fuel tank. This approach decouples fuel feeding and electricity generation, providing greater operation flexibility and scalability for large‐scale power generation applications. The DHPS‐mediated ZAFC exhibited a superior peak power density of 0.51 W/cm2 and a continuous discharge capacity of 48.82 Ah with ZnO as the discharge product in the tank, highlighting its potential for power generation. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) have been proposed for electrochemical energy storage, although the poor conductivity resulted from covalent bonds limits their practical performance. Here, we propose to introduce noncovalent bonds in COFs through a molecular insertion strategy for improving the conductivity of the COFs as supercapacitor. The synthesized COFs (MI−COFs) establish equilibriums between covalent bonds and noncovalent bonds, which construct a continuous charge transfer channel to enhance the conductivity. The rapid charge transfer rate enables the COFs to activate the redox sites, bringing about excellent electrochemical energy storage behavior. The results show that the MI−COFs exhibit much better performance in specific capacitance and capacity retention rate than those of most COFs‐based supercapacitors. Moreover, through simply altering inserted guests, the mode and strength of noncovalent bond can be adjusted to obtain different energy storage characteristics. The introduction of noncovalent bonds is an effective and flexible way to enhance and regulate the properties of COFs, providing a valuable direction for the development of novel COFs‐based energy storage materials. [ABSTRACT FROM AUTHOR]

Self‐assembly of subnanometer (sub‐1 nm) scale polyhedral building blocks can yield some superstructures with novel and interesting morphology as well as potential functionalities. However, achieving the self‐assembly of sub‐1 nm polyhedral building blocks is still a great challenge. Herein, through encapsulating the titanium‐substituted polyoxometalate (POM, K7PTi2W10O40) with tetrabutylammonium cations (TBA+), we first synthesized a sub‐1 nm rhombic dodecahedral building block by further tailoring the spatial distribution of TBA+ on the POM. Molecular dynamics (MD) simulations demonstrated the eight TBA+ cations interacted with the POM cluster and formed the sub‐1 nm rhombic dodecahedron. As a result of anisotropy, the sub‐1 nm building blocks have self‐assembled into rhombic dodecahedral POM (RD‐POM) assemblies at the microscale. Benefiting from the regular structure, Br− ions, and abundant active sites, the obtained RD‐POM assemblies exhibit excellent catalytic performance in the cycloaddition of CO2 with epoxides without co‐catalysts. This work provides a promising approach to tailor the symmetry and structure of sub‐1 nm building blocks by tuning the spatial distribution of ligands, which may shed light on the fabrication of superstructures with novel properties by self‐assembly. [ABSTRACT FROM AUTHOR]

Transition metal oxide (TMO) anode materials in lithium‐ion batteries (LIBs) usually suffer from serious volume expansion leading to the pulverization of structures, further giving rise to lower specific capacity and worse cycling stability. Herein, by introducing polyoxometalate (POM) clusters into TMOs and precisely controlling the amount of POMs, the MnZnCuOx‐phosphomolybdic acid hybrid sub‐1 nm nanosheets (MZC‐PMA HSNSs) anode is successfully fabricated, where the special electron rich structure of POMs is conducive to accelerating the migration of lithium ions on the anode to obtain higher specific capacity, and the non‐covalent interactions between POMs and TMOs make the HSNSs possess excellent structural and chemical stability, thus exhibiting outstanding electrochemical performance in LIBs, achieving a high reversible capacity (1157 mAh g−1 at 100 mA g−1) and an admirable long‐term cycling stability at low and high current densities. [ABSTRACT FROM AUTHOR]

Two‐dimensional (2D) AIE‐inorganic nanocomposites exhibit high stability and high fluorescence activity. However, limited by the types and properties of 2D inorganic materials, it's challenging to realize complex structures and functions. We designed a quaternary ammonium‐type AIE ligand, TPECholine. We chose TPECholine and POM clusters as building blocks and synthesized a series of single‐layer nanosheets (SLNSs) by assembling LnW10 or P2W18 POM clusters with TPECholine. By regulating the types of POM clusters and ligands, the morphology and fluorescence intensity of the SLNSs can be finely tuned. Due to the restriction of the intramolecular motions of AIEgens by the SLNSs, nanosheets can exhibit promoted quantum yield (up to 76 %). In addition, thanks to the sub‐nanometric sizes and excess surface charges, SLNSs exhibit excellent solvent compatibility, including water, chloroform, ethanol, etc. And the nanosheets showed high fluorescence intensity in these solvents. [ABSTRACT FROM AUTHOR]

Polyoxometalate (POM) clusters with atomic precision structures are promising candidates construct functional nanomaterials via self‐assembly. Non‐covalent interactions at molecular levels can govern the self‐assembly of POM clusters, for which the precise control of POM‐based assemblies can be realized at single‐cluster levels. This mini‐review focuses on the synthesis and properties of POM‐based nanostructures, including amphiphilic POM assemblies and co‐assemblies of POM clusters and other subnanometer building blocks. Several synthetic strategies have been developed for rational control of POM‐based assemblies in terms of morphologies, compositions and properties. 1D subnanometer POM assemblies demonstrate remarkable enhanced mechanical properties due to the topological interactions between nanowires and surroundings. The in‐depth understanding of POM‐based assemblies may help in the design of functional nanomaterials in fundamental perspectives and applications. [ABSTRACT FROM AUTHOR]

Sub‐nanowires (SNWs) exhibit great potential applications in nanocomposites owing to their high specific surface area, high flexibility, and similarity to polymer chains in dimension, which are a good entry point to bridge inorganic materials and polymer materials. Herein, we synthesized hydroxyapatite sub‐nanowires (HAP SNWs) and engineered hydroxyapatite sub‐nanowires/polyimide (HSP) gels and films by simple mixing of HAP SNWs and polyimide (PI). Benefiting from the interactions between HAP SNWs and PI, these nanocomposites were a continuous hybrid network. As the increase of HAP SNWs contents, the viscosity and modulus of HSP gels were greatly improved by one or two orders of magnitude compared with PI gel. HSP films not only maintained high transparency but also gained high haze, as well as exhibited enhanced Young's modulus. Thus, both HSP gels and films developed in this work are promising for various applications in coatings and high‐performance films. [ABSTRACT FROM AUTHOR]

Sub‐1 nm nanowires (SNWs) combine the properties of inorganic materials and polymers. They can be highly oriented through assembly, and can also be easily processed. Meanwhile, aggregation‐induced emission luminogens (AIEgens) show high potential for optical applications, but they are usually hard to process. The combination of SNWs and AIEgens can enrich both of their applications. In this study, we report that the fluorescence emission intensity of the AIEgens–SNW dispersion is dramatically enhanced due to the flexibility of SNWs. Furthermore, we fabricate two kinds of functional films with circularly polarized luminescence (CPL) and linearly polarized luminescence (LPL) activities. The construction of CPL materials didn't require any chiral chemicals. The construction of LPL materials didn't require an additional stretching process. As a result, we endowed common achiral AIEgens with a high dissymmetry factor of 0.033 and a polarization ratio of 0.44, respectively. [ABSTRACT FROM AUTHOR]

This work presents a redox‐mediated electrolytic nitrogen reduction reaction (RM‐eNRR) using polyoxometalate (POM) as the electron and proton carrier which frees the TiO2‐based catalyst from the electrode and shifts the reduction of nitrogen to a reactor tank. The RM‐eNRR process has achieved an ammonium production yield of 25.1 μg h−1 or 5.0 μg h−1 cm−2 at an ammonium concentration of 6.7 ppm. With high catalyst loading, 61.0 ppm ammonium was accumulated in the electrolyte upon continuous operation, which is the highest concentration detected for ambient eNRR so far. The mechanism underlying the RM‐eNRR was scrutinized both experimentally and computationally to delineate the POM‐mediated charge transfer and hydrogenation process of nitrogen molecule on the catalyst. RM‐eNRR is expected to provide an implementable solution to overcome the limitations in the conventional eNRR process. [ABSTRACT FROM AUTHOR]

Microporous materials are extensively used in catalysis due to their unique pore structures. Among them, microporous materials loaded with polyoxometalates (POMs) exhibit considerable potential for catalysis thanks to the combination of the outstanding redox‐catalytic properties of POMs and the characteristics of microporous materials. Based on this, we developed a facile hydrothermal method to synthesize helical microporous nanorods (HMNRs) using POM clusters as building blocks, combining the properties of both POMs and microporous materials while circumventing the complicated loading process. The HMNRs show an enhanced photocatalytic performance for toluene oxidation. Comparatively high activity, superior selectivity towards benzaldehyde, and prominent cycling stability were achieved, manifesting a promising prospect for a future application in photocatalysis. [ABSTRACT FROM AUTHOR]

Developing two‐dimensional (2D) and single atomic layered materials is a fascinating challenge. Here we successfully synthesize porphyrin‐based monoatomic layer (PML), a freestanding 2D porphyrin‐based material of monomer‐unit thickness (2.8 Å). The solvothermal method provides a bottom‐up approach for tailoring the monoatomic layer from the nanoscale to the milliscale. PMLs containing accurately tailorable M‐N4 units (M=Cu and Au) were synthesized, which present metal center‐dependent performance for CO2 electrocatalysis. PML with Cu‐N4 centers performs high faradaic efficiencies of HCOO− and CH4 (80.86 % and 11.51 % at −0.7 V, respectively) while PML with Au‐N4 centers generates HCOO− and CO as major products (40.90 % and 34.40 % at −0.8 V, respectively). Irreversible restructuring behavior of Cu sites is also observed. Based on the graphene‐like properties and metal center‐selectivity relationships, we believe that PML will play a distinct role in various applications. [ABSTRACT FROM AUTHOR]

Controlling the interaction of polarization light with an asymmetric nanostructure such as a metal/semiconductor heterostructure provides opportunities for tuning surface plasmon excitation and near‐field spatial distribution. However, light polarization effects on interfacial charge transport and the photocatalysis of plasmonic metal/semiconductor photocatalysts are unclear. Herein, we reveal the polarization dependence of plasmonic charge separation and spatial distribution in Au/TiO2 nanoparticles under 45° incident light illumination at the single‐particle level using a combination of photon‐irradiated Kelvin probe force microscopy (KPFM) and electromagnetic field simulation. We quantitatively uncover the relationship between the local charge density and polarization angle by investigating the polarization‐dependent surface photovoltage (SPV). The plasmon‐induced photocatalytic activity is enhanced when the polarization direction is perpendicular to the Au/TiO2 interface. [ABSTRACT FROM AUTHOR]

Utilizing sustainable energy for chemical activation of small molecules, such as CO2, to produce important chemical feedstocks is highly desirable. The simultaneous production of CO/H2 mixture (syngas) from photoreduction of CO2 and H2O is highly promising. However, the relationships between structure, composition, crystallinity, and photocatalytic performance are still indistinct. Here, amorphous ultrathin CoO nanowires and polyoxometalate incorporated nanowires with even lower crystallinity were synthesized. The POM‐incorporated ultrathin nanowires exhibit high photocatalytic syngas production activity, reaching H2 and CO evolution rates of 11555 and 4165 μmol g−1 h−1 respectively. Further experiments indicate that the ultrathin morphology and incorporation of POM both contribute to the superior performance. Multiple characterizations reveal the enhanced charge–hole separation efficiency of the catalyst would facilitate the photocatalysis. [ABSTRACT FROM AUTHOR]

Aqueous organic redox flow batteries (AORFBs) have received considerable attention for large‐scale energy storage. Quinone derivatives, such as 9,10‐anthraquinone‐2,7‐disulphonic acid (2,7‐AQDS), have been explored intensively owing to potentially low cost and swift reaction kinetics. However, the low solubility in pH‐neutral electrolytes restricts their application to corrosive acidic or caustic systems. Herein, the single molecule redox‐targeting reactions of 2,7‐AQDS anolyte are presented to circumvent its solubility limit in pH‐neutral electrolytes. Polyimide was employed as a low‐cost high‐capacity solid material to boost the capacity of 2,7‐AQDS electrolyte to 97 Ah L−1. Through in situ FTIR spectroscopy, a hydrogen‐bonding mediated reaction mechanism was disclosed. In conjunction with NaI as catholyte and nickel hexacyanoferrate as the catholyte capacity booster, a single‐molecule redox‐targeting reaction‐based full cell with energy density up to 39 Wh L−1 was demonstrated. [ABSTRACT FROM AUTHOR]

A single‐step solution‐based strategy is used to obtain 2D Janus‐like free‐standing ultrathin nanosheets build from two structurally unrelated species, that is, polyoxomolybdate (POM) and CoO. A controlled 2D‐to‐1D morphological transition was achieved by judiciously adjusting the solvent choice. These POM‐CoO heterostructures can behave as an ideal catalyst for the epoxidation of styrene. Benefiting from their amphiphilic nature, these 2D POM‐CoO nanosheets have also been used as surfactant to emulsify immiscible solvents. It is anticipated that structurally diverse polyoxometalates will offer promise as design elements for variety of structurally and compositionally tunable van der Waals integrated heteromaterials having a broad range applications. [ABSTRACT FROM AUTHOR]

Inorganic single crystals with anisotropic structures usually suffer from high brittleness and stiffness. Flexible polymers are used to replace inorganic crystals, but the hot‐stretching‐induced orientation process is tedious, and oriented molecular chains tend to revert to random coils during aging. To overcome these obstacles and using the similarities between sub‐1 nm nanowires (NWs) and linear polymers, we successfully fabricated anisotropic, transparent, flexible, and stable (ATFS) NW films with great potential for optical applications through a wet‐spinning method. The NW films show birefringence, and their birefractive index is higher than that of many polymers. They also showed polarized absorption of UV light and anisotropic scattering of visible light. The integrated films composed of NWs and quantum dots showed good fluorescence polarization. The tedious synthesis of quantum rods and fabrication of oriented polymer films can thus be avoided. [ABSTRACT FROM AUTHOR]

Abstract: MOFs are a type of ideal crystalline material with rigid reticular structures whereas microcapsules are usually prepared from soft mater, such as polymers or supramolecules. The synthesis of MOF‐based microcapsules with novel nanostructures at the molecular scale remains a great challenge. Herein, we develop a competitive coordination strategy to synthesize MOF‐based microcapsules with novel bowl‐like structures. During the competitive coordination process, the infinite structures of MOFs are partially broken by the competitive reagents, thus flexibility is introduced into the rigid skeletons and results in the formation of bowl‐like microcapsules. Owing to the unique structure and composition of these nano‐structures, the microcapsules exhibit excellent performance and stability in adsorbing and removing iodine for both vapor and solution. This work describes new opportunities in designing MOF‐based microcapsules with novel structures. [ABSTRACT FROM AUTHOR]

Abstract: Single atoms immobilized on metal–organic frameworks (MOFs) with unique nanostructures have drawn tremendous attention in the application of catalysis but remain a great challenge. Various single noble‐metal atoms have now been successfully anchored on the well‐defined anchoring sites of the zirconium porphyrin MOF hollow nanotubes, which are probed by aberration‐corrected scanning transmission electron microscopy and synchrotron‐radiation‐based X‐ray absorption fine‐structure spectroscopy. Owing to the hollow structure and excellent photoelectrochemical performance, the HNTM‐Ir/Pt exhibits outstanding catalytic activity in the visible‐light photocatalytic H2 evolution via water splitting. The single atom immobilized on MOFs with hollow structures are expected to pave the way to expand the potential applications of MOFs. [ABSTRACT FROM AUTHOR]

Multidimensional nano-heterostructures (NHSs) that have unique dimensionality-dependent integrative and synergic effects are intriguing but still underdeveloped. Here, we report the first helical 1D/2D epitaxial NHS between CdS and ZnIn2S4. Experimental and theoretical studies reveal that the mismatches in lattice and dangling bonds between 1D and 2D units govern the growth procedure. The resulting well-defined interface induces the delocalized interface states, thus facilitate the charge transfer and enhance the performance in the photoelectrochemical cells. We foresee that the mechanistic insights gained and the electronic structures revealed would inspire the design of more complex 1D/2D NHSs with outstanding functionalities. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) have demonstrated great potentials in a variety of important applications. To enhance the inherent properties and endow materials with multifunctionality, the rational design and synthesis of MOFs with nanoscale porosity and hollow feature is highly desired and remains a great challenge. In this work, the formation of a series of well-defined MOF (MOF-5, FeII-MOF-5, FeIII-MOF-5) hollow nanocages by a facile solvothermal method, without any additional supporting template is reported. A surface-energy-driven mechanism may be responsible for the formation of hollow nanocages. The addition of pre-synthesized poly(vinylpyrrolidone)- (PVP) capped noble-metal nanoparticles into the synthetic system of MOF hollow nanocages yields the yolk-shell noble metal@MOF nanostructures. The present strategy to fabricate hollow and yolk-shell nanostructures is expected to open up exciting opportunities for developing a novel class of inorganic-organic hybrid functional nanomaterials. [ABSTRACT FROM AUTHOR]

Cluster aggregation states are thermodynamically favored at the subnanoscale, for which an inverse growth from nanoparticles to clusters may be realized on subnanometer supports. Herein, we develop Au‐polyoxometalate‐layered double hydroxide (Au‐POM‐LDH) sub‐1 nm nanosheets (Sub‐APL) based on the above strategy, where sub‐1 nm Au clusters with negative valence are generated by the in situ disintegration of Au nanoparticles on POM‐LDH supports. Sub‐1 nm Au clusters with ultrahigh surface atom ratios exhibit remarkable efficiency for glutathione (GSH) depletion. The closely connected sub‐1 nm Au with negative valence and POM hetero‐units can promote the separation of hole‐electrons, resulting in the enhanced reactive oxygen species (ROS) generation under ultrasound (US). Besides, the reversible redox of Mo in POM is able to deplete GSH and trigger chemodynamic therapy (CDT) simultaneously, further enhancing the oxidative stress. Consequently, the Sub‐APL present 2‐fold ROS generation under US and 7‐fold GSH depletion compared to the discrete Au and POM‐LDH mixture. Therefore, the serious imbalance of redox in the TME caused by the sharp increase of ROS and rapid decrease of GSH leads to death of tumor ultimately. [ABSTRACT FROM AUTHOR]

Utilizing sustainable energy for chemical activation of small molecules, such as CO2, to produce important chemical feedstocks is highly desirable. The simultaneous production of CO/H2 mixture (syngas) from photoreduction of CO2 and H2O is highly promising. However, the relationships between structure, composition, crystallinity, and photocatalytic performance are still indistinct. Here, amorphous ultrathin CoO nanowires and polyoxometalate incorporated nanowires with even lower crystallinity were synthesized. The POM‐incorporated ultrathin nanowires exhibit high photocatalytic syngas production activity, reaching H2 and CO evolution rates of 11555 and 4165 μmol g−1 h−1 respectively. Further experiments indicate that the ultrathin morphology and incorporation of POM both contribute to the superior performance. Multiple characterizations reveal the enhanced charge–hole separation efficiency of the catalyst would facilitate the photocatalysis. [ABSTRACT FROM AUTHOR]