http://onlinelibrary.wiley.com/rss/journal/10.1002/(ISSN)1521-4095

Increasing cellular immunogenicity and reshaping the immune tumor microenvironment (TME) are crucial for anti-tumor immunotherapy. Herein, we developed a novel single-atom nanozyme pyroptosis initiator: UK5099 and pyruvate oxidase (POx)-co-loaded Cu-NS single-atom nanozyme (Cu-NS@UK@POx), that not only triggers pyroptosis through cascade biocatalysis to boost the immunogenicity of tumor cells, but also remodels the immunosuppressive TME by targeting pyruvate metabolism. By replacing N with weakly electronegative S, we changed the original spatial symmetry of the Cu-N4 electron distribution and effectively regulated the enzyme-catalyzed process. Compared to spatially symmetric Cu-N4 single-atom nanozymes (Cu-N4 SA), the S-doped spatially asymmetric single-atom nanozymes (Cu-NS SA) exhibit stronger oxidase activities, including peroxidase (POD), nicotinamide adenine dinucleotide (NADH) oxidase (NOx), L-cysteine oxidase (LCO) and glutathione oxidase (GSHOx), which can cause enough reactive oxygen species (ROS) storms to trigger pyroptosis. Moreover, the synergistic effect of Cu-NS SA, UK5099, and POx can target pyruvate metabolism, which not only improves the immune TME but also increases the degree of pyroptosis. This study provides a two-pronged treatment strategy that can significantly activate antitumor immunotherapy effects via ROS storms, NADH/glutathione/L-cysteine consumption, pyruvate oxidation, and lactic acid/ATP depletion, triggering pyroptosis and regulating metabolism. This work provides a broad vision for expanding antitumor immunotherapy.

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Two-dimensional (2D) lateral heterojunction arrays, characterized by well-defined electronic interfaces, hold significant promise for advancing next-generation electronic devices. Despite this potential, the efficient synthesis of high-density lateral heterojunctions with tunable interfacial band alignment remains a challenging. Here, a novel strategy is reported for the fabrication of lateral heterojunction arrays between monolayer Si2Te2 grown on Sb2Te3 (ML-Si2Te2@Sb2Te3) and one-quintuple-layer Sb2Te3 grown on monolayer Si2Te2 (1QL-Sb2Te3@ML-Si2Te2) on a p-doped Sb2Te3 substrate. The site-specific formation of numerous periodically arranged 2D ML-Si2Te2@Sb2Te3/1QL-Sb2Te3@ML-Si2Te2 lateral heterojunctions is realized solely through three epitaxial growth steps of thick-Sb2Te3, ML-Si2Te2, and 1QL-Sb2Te3 films, sequentially. More importantly, the precisely engineering of the interfacial band alignment is realized, by manipulating the substrate's p-doping effect with lateral spatial dependency, on each ML-Si2Te2@Sb2Te3/1QL-Sb2Te3@ML-Si2Te2 junction. Atomically sharp interfaces of the junctions with continuous lattices are observed by scanning tunneling microscopy. Scanning tunneling spectroscopy measurements directly reveal the tailored type-II band bending at the interface. This reported strategy opens avenues for advancing lateral epitaxy technology, facilitating practical applications of 2D in-plane heterojunctions.

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The anion-specific effects of the salting-in and salting-out phenomena have been extensively observed in hydrogels, whereas the cation specificity of hydrogels has rarely been reported. Herein, a multi-step strategy including borax pre-gelation, saline soaking, freeze-drying, and rehydrating is developed to fabricate polyvinyl alcohol gels with cation specificity, exhibiting the specific ordering of effects on the mechanical properties of gels as Ca2+ > Li+ > Mg2+ >> Fe3+ > Cu2+ ≈ Co2+ ≈ Ni2+ ≈ Zn2+. The multiple effects of the fabrication strategy, including the electrostatic repulsion among cations, skeleton support function of graphene oxide nanosheets, and water absorption and retention of ions, endow the gels with the dual characteristics of hydrogels and aerogels (i.e., hydro-aerogels). The hydro-aerogels prepared with the cationic salting-out effect display attractive pressure sensing performance with excellent stability over 90 days and enable continuous monitoring of ambient humidity in real time and effective work in seawater to detect various parameters (e.g., depth, salinity, and temperature). The hydro-aerogels prepared using the cationic salting-in effect can serve as quasi-solid-state electrolytes in supercapacitors, with 99.59% capacitance retention after 10,000 cycles. This study realizes cation specificity in hydrogels and designs multifunctional hydro-aerogels for promising applications in various fields.

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Spinal cord injury (SCI) is a refractory neurological disorder. Due to the complex pathological processes, especially the secondary inflammatory cascade and the lack of intrinsic regenerative capacity, it is difficult to recover neurological function after SCI. Meanwhile, simulating the conductive microenvironment of the spinal cord promises to reconstruct electrical neural signal transmission interrupted by SCI and facilitates the neural repair. A double-crosslinked conductive hydrogel (BP@Hydrogel) containing black phosphorus nanoplates (BP) is synthesized. When placed in a rotating magnetic field (RMF), the BP@Hydrogel can generate stable electrical signals and exhibit electrogenic characteristic. In vitro, the BP@Hydrogel shows satisfactory biocompatibility and can alleviate the activation of microglia. When placed in the RMF, it enhances the anti-inflammatory effects. Meanwhile, the wireless electrical stimulation promotes the differentiation of neural stem cells (NSCs) to neurons, which is associated with the activation of the PI3K/AKT pathway. In vivo, the BP@Hydrogel is injectable and could elicit behavioral and electrophysiological recovery in complete transected SCI mice by alleviating the inflammation and facilitating endogenous NSCs to form functional neurons and synapses under the RMF. The present research develops a multifunctional conductive and electrogenic hydrogel for SCI repair by targeting multiple mechanisms including immunoregulation and enhancement of neuronal differentiation.

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Functional amyloid from bacteria, particularly CsgA and FapC, are emerging as promising new biomaterials with applications within areas as diverse as gastrointestinal colonization, tissue engineering, water purification, CO2 fixation, biosensing, and more recently biocatalysis. This is thanks to their high stability, efficient and controllable formation, easy and scalable availability and ready engineering opportunities.

Functional amyloid (FAs), particularly the bacterial proteins CsgA and FapC, have many useful properties as biomaterials: high stability, efficient, and controllable formation of a single type of amyloid, easy availability as extracellular material in bacterial biofilm and flexible engineering to introduce new properties. CsgA in particular has already demonstrated its worth in hydrogels for stable gastrointestinal colonization and regenerative tissue engineering, cell-specific drug release, water-purification filters, and different biosensors. It also holds promise as catalytic amyloid; existing weak and unspecific activity can undoubtedly be improved by targeted engineering and benefit from the repetitive display of active sites on a surface. Unfortunately, FapC remains largely unexplored and no application is described so far. Since FapC shares many common features with CsgA, this opens the window to its development as a functional scaffold. The multiple imperfect repeats in CsgA and FapC form a platform to introduce novel properties, e.g., in connecting linkers of variable lengths. While exploitation of this potential is still at an early stage, particularly for FapC, a thorough understanding of their molecular properties will pave the way for multifunctional fibrils which can contribute toward solving many different societal challenges, ranging from CO2 fixation to hydrolysis of plastic nanoparticles.

Despite the increasing effort in advancing oxygen electrocatalysts for zinc-air batteries (ZABs), the performance development gradually reaches a plateau via only ameliorating the electrocatalyst materials. Herein, a new class of external field-responsive electrocatalyst comprising Ni0.5Mn0.5Fe2O4 stably dispersed on N-doped Ketjenblack (Ni0.5Mn0.5Fe2O4/N-KB) was developed via polymer-assisted strategy for practical ZABs. Briefly, the activity indicator ΔE was significantly decreased to 0.618 V upon photothermal assistance, far exceeding most reported electrocatalysts (generally >0.680 V). As a result, the photothermal electrocatalyst possessed comprehensive merits of excellent power density (319 mW cm−2), ultralong lifespan (5163 cycles at 25 mA cm−2) and outstanding rate performance (100 mA cm−2) for liquid ZABs, and superb temperature and deformation adaptability for flexible ZABs. Such improvement was attributed to the photothermal-heating-enabled synergy of promoted electrical conductivity, reactant-molecule motion, active area and surface reconstruction, as revealed by operando Raman and simulation. The findings open vast possibilities toward more-energy-efficient energy applications.

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Hypoxia and infection are urgent clinical problems in chronic diabetic wounds. Herein, living Chlorella-loaded poly(ionic liquid)-based microneedles (PILMN-Chl) were constructed for microacupuncture oxygen and antibacterial therapy against methicillin-resistant Staphylococcus aureus (MRSA)-infected chronic diabetic wounds. The PILMN-Chl can stably and continuously produce oxygen for more than 30 h due to the photosynthesis of the loaded self-supported Chlorella. By combining the barrier penetration capabilities of microneedles, the continuous and sufficient oxygen supply of Chlorella and the sterilization activities of PIL, the PILMN-Chl can accelerate chronic diabetic wounds in vivo by topical targeted sterilization and hypoxia relief in deep parts of wounds. Thus, the self-oxygen produced microneedles modality may provide a promising and facile therapeutic strategy for treating chronic, hypoxic, and infected diabetic wounds.

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To address the problems associated with Li metal anodes, we present a fluoride-rich solid-like electrolyte (SLE) that combines the benefits of solid-state and liquid electrolytes. Its unique triflate-group-enhanced frame channels facilitate the formation of a functional inorganic-rich solid electrolyte interphase (SEI), which not only improves the reversibility and interfacial charge transfer of Li anodes but also ensures uniform and compact Li deposition. Furthermore, these triflate groups contribute to the decoupling of Li+ and provide hopping sites for rapid Li+ transport, enabling a high room-temperature ionic conductivity of 1.1 mS cm−1 and a low activation energy of 0.17 eV, making it comparable to conventional liquid electrolytes. Consequently, Li symmetric cells using such SLE achieve extremely stable plating/stripping cycling over 3500 h at 0.5 mA cm−2 and support a high critical current up to 2.0 mA cm−2. The assembled Li||LiFePO4 solid-like batteries exhibit exceptional cyclability for over one year and a half, even outperforming liquid cells. Additionally, high-voltage cylindrical cells and high-capacity pouch cells are demonstrated, corroborating much simpler processibility in battery assembly compared to all solid-state batteries. These findings highlight the potential of the SLE approach in building a desirable SEI, offering practical solutions for the widespread adoption of rechargeable LMBs.

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Bioengineering strategies for the fabrication of implantable lymphoid structures mimicking lymph nodes (LNs) and tertiary lymphoid structures (TLS) could amplify the adaptive immune response for therapeutic applications such as cancer immunotherapy. No method to date has resulted in the consistent formation of high endothelial venules (HEVs), which is the specialized vasculature responsible for naïve T cell recruitment and education in both LNs and TLS. Here we used orthogonal induced differentiation of human pluripotent stem cells (hPSCs) carrying a regulatable ETV2 allele, to rapidly and efficiently induce endothelial differentiation. Assembly of embryoid bodies combining primitive inducible endothelial cells (iEndos) and primary human lymph node fibroblastic reticular cells (FRCs) resulted in the formation of HEV-like structures that can aggregate into three dimensional organoids (HEVOs). Upon transplantation into immunodeficient mice, HEVOs successfully engrafted and formed lymphatic structures that recruited both antigen-presenting cells and adoptively-transferred lymphocytes, therefore displaying basic TLS capabilities. Our results further show that functionally, HEVOs can organize an immune response and promote anti-tumor activity by adoptively transferred T lymphocytes. Collectively, our experimental approaches represent an innovative and scalable proof-of-concept strategy for the fabrication of bioengineered tertiary lymphoid structures that can be deployed in vivo to enhance adaptive immune responses.

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Layered materials are characterized by strong in-plane covalent chemical bonds within each atomic layer and weak out-of-plane van der Waals (vdW) interactions between adjacent layers. The non-bonding nature between neighboring layers naturally results in a vdW gap, which enables the insertion of guest species into the interlayer gap. Rational design and regulation of interlayer nanochannels are crucial for converting these layered materials and their two-dimensional derivatives into ion separation membranes or battery electrodes. Herein, based on the latest progress in layered materials and their derivative nanosheets, various interlayer engineering methods are briefly introduced, along with the effects of intercalated species on the crystal structure and interlayer coupling of the host layered materials. Their applications in the ion separation and energy storage fields are then summarized, with the focus on interlayer engineering to improve selective ion transport and ion storage performance. Finally, future research opportunities and challenges in this emerging field are comprehensively discussed.

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Generation and control of topological spin textures constitutes one of the most exciting challenges of modern spintronics given their potential applications in information storage technologies. Of particular interest are magnetic insulators, which due to low damping, absence of Joule heating and reduced dissipation could provide energy-efficient spin-textures platform. Here we demonstrate that the interplay between sample thickness, external magnetic fields and optical excitations can generate a prolific paramount of spin textures, and their coexistence in insulating CrBr3 van der Waals (vdW) ferromagnets. Using high-resolution magnetic force microscopy and large-scale micromagnetic simulation methods, we demonstrate the existence of a large region in T-B phase diagram where different stripe domains, skyrmion crystals and magnetic domains exist and can be intrinsically selected or transformed to each-other via a phase-switch mechanism. Lorentz transmission electron microscopy unveiled the mixed chirality of the magnetic textures which are of Bloch-type at given conditions but can be further manipulated into Néel-type or hybrid-type via thickness-engineering. The topological phase transformation between the different magnetic objects could be further inspected by standard photoluminescence optical probes resolved by circular polarization indicative of an existance of exciton-skyrmion coupling mechanism. Our findings identified vdW magnetic insulators as a promising framework of materials for the manipulation and generation of highly ordered skyrmion lattices relevant for device integration at the atomic level.

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Nanoscale metallic glasses offer opportunities for investigating fundamental properties of amorphous solids and technological applications in biomedicine, microengineering, and catalysis. However, their top-down fabrication is limited by bulk counterpart availability, and bottom-up synthesis remains underexplored due to strict formation conditions. Here, we developed a kinetically controlled flash carbothermic reaction, featuring ultrafast heating (>105 K s−1) and cooling rates (>104 K s−1), for synthesizing metallic glass nanoparticles within milliseconds. Nine compositional permutations of noble metals, base metals, and metalloid (M1-M2-P, M1 = Pt/Pd, M2 = Cu/Ni/Fe/Co/Sn) were synthesized with widely tunable particle sizes and substrates. Through combinatorial development, we discovered a substantially expanded composition space for nanoscale metallic glass compared to bulk counterpart, revealing the nanosize effect enhanced glass forming ability. Leveraging this, we synthesized several nanoscale metallic glasses with composition that have never, to our knowledge, been synthesized in bulk. The metallic glass nanoparticles exhibited high activity in heterogeneous catalysis, outperforming crystalline metal alloy nanoparticles.

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The exploration of high-performance and low-cost wide-bandgap polymer donors remains critical to achieve high-efficiency non-fullerene organic solar cells (OSCs) beyond current thresholds. Herein, the 1,2,3-benzothiadiazole (iBT), which is an isomer of 2,1,3-benzothiadiazole (BT), is used to design wide-bandgap polymer donor PiBT. The PiBT-based solar cells reach efficiency of 19.0%, which is one of the highest efficiencies in binary OSCs. Systemic studies show that isomerization of 2,1,3-benzothiadiazole (BT) to 1,2,3-benzothiadiazole (iBT) can finely regulate the polymers’ photoelectric properties including (i) increase the extinction coefficient and photon harvest, (ii) down-shift the highest occupied molecular orbital (HOMO) energy levels, (iii) improve the coplanarity of polymer backbones, (vi) offer good thermodynamic miscibility with acceptors. Consequently, the PiBT:Y6 BHJ device simultaneously reaches advantageous nanoscale morphology, efficient exciton generation and dissociation, fast charge transportation, and suppressed charge recombination, leading to larger V OC of 0.87 V, higher J SC of 28.2 mA·cm−2, greater FF of 77.3%, and thus higher efficiency of 19.0%, while the analogue PBT-based OSCs reach efficiency of only 12.9%. Moreover, the key intermediate 1,2,3-benzothiadiazole (iBT) can be easily afforded from industry chemicals via two-step procedure. Overall, this contribution highlights that 1,2,3-benzothiadiazole (iBT) is a promising motif for designing high-performance polymer donors.

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Delivery of therapeutics to solid tumors with high bioavailability remains a challenge and is likely the main contributor to the ineffectiveness of immunotherapy and chemotherapy. Here, a catheter-directed ionic liquid embolic (ILE) was bioengineered to achieve durable vascular embolization, uniform tissue ablation, and drug delivery in non-survival and survival porcine models of embolization, outperforming the clinically used embolic agents. To simulate the clinical scenario, rabbit VX2 orthotopic liver tumors were treated showing successful trans-arterial delivery of Nivolumab and effective tumor ablation. Furthermore, similar results were also observed in human ex-vivo tumor tissue as well as significant susceptibility of highly resistant patient-derived bacteria was seen to ILE, suggesting that ILE could prevent abscess formation in embolized tissue. ILE represents a new class of liquid embolic agents that can treat tumors, improve the delivery of therapeutics, prevent infectious complications, and potentially increase chemo- and immunotherapy response in solid tumors.

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Diverse and adaptable modes of complex motion observed at different scales in living creatures are challenging to reproduce in robotic systems. Achieving dexterous movement in conventional robots can be difficult due to the many limitations of applying rigid materials. Robots based on soft materials are inherently deformable, compliant, adaptable, and adjustable, making soft robotics conducive to creating machines with complicated actuation and motion gaits. This review examines the mechanisms and modalities of actuation deformation in materials that respond to various stimuli. Then, strategies based on composite materials are considered to build toward actuators that combine multiple actuation modes for sophisticated movements. Examples across literature illustrate the development of soft actuators as free-moving, entirely soft-bodied robots with multiple locomotion gaits via careful manipulation of external stimuli. We further highlight how the application of soft functional materials into robots with rigid components further enhances their locomotive abilities. Finally, taking advantage of the shape-morphing properties of soft materials, reconfigurable soft robots have shown the capacity for adaptive gaits that enable transition across environments with different locomotive modes for optimal efficiency. Overall, soft materials enable varied multimodal motion in actuators and robots, positioning soft robotics to make real-world applications for intricate and challenging tasks.

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In addition to their potential for reducing solid waste streams associated with discarded consumer gadgetry, bio/ecoresorbable electronic systems create unique opportunities in implantable medical devices that serve a need over a finite time period and then disappear naturally to eliminate the need for extraction surgeries. A critical challenge in the development of this type of technology is in materials that can serve as thin, stable barriers to surrounding ground water or biofluids, yet ultimately dissolve completely and in a well-defined manner to biologically and environmentally benign end products. Here, we describe a class of inorganic material (silicon oxynitride, SiON) that can be formed in thin films by plasma-enhanced chemical vapor deposition (PECVD) for this purpose. In vitro studies suggest that SiON and its dissolution products are biocompatible, indicating the potential for its use in implantable devices. A facile process to fabricate flexible, wafer-scale multilayer films bypasses limitations associated with the mechanical fragility of inorganic thin films. Systematic computational, analytical and experimental studies highlight the essential materials aspects. Demonstrations in wireless light-emitting diodes (LEDs) both in vitro and in vivo illustrate the practical use of these materials strategies. The ability to select degradation rates and water permeability through fine tuning of chemical compositions and thicknesses provides the opportunity to obtain a range of functional lifetimes to meet different application requirements.

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Two-photon polymerization (2PP) is becoming increasingly established as additive manufacturing technology for micro-fabrication due to its high-resolution and the feasibility of generating complex parts. Until now, the high resolution of 2PP was also its bottleneck, as it limited throughput and therefore restricted the application to the production of micro-parts. Thus, mechanical properties of 2PP materials could only be characterized using non-standardized specialized micro-testing methods. Due to recent advances in 2PP technology, it is now possible to produce parts in the size of several millimeters to even centimeters, finally permitting the fabrication of macro-sized testing specimens. Besides suitable hardware systems, 2PP materials exhibiting favorable mechanical properties that allow printing of up-scaled parts are strongly demanded. In this work, the up-scalability of three different photopolymers is investigated using a high-throughput 2PP system and low numerical aperture optics. Testing specimens in the cm-range were produced and tested with common or even standardized material testing methods available in conventionally equipped polymer testing labs. Examples of the characterization of mechanical, thermo-mechanical, and fracture properties of 2PP processed materials are shown. Additionally, aspects such as post-processing and aging have been investigated. This lays a foundation for future expansion of the 2PP technology to broader industrial application.

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Surface-enhanced Raman spectroscopy (SERS) is an ultrasensitive surface analysis technique that is widely used in chemical sensing, bioanalysis, and environmental monitoring. The design of the SERS substrates is crucial for obtaining high-quality SERS signals. Recently, two-dimensional transition metal dichalcogenides (2D TMDs) have emerged as high-performance SERS substrates due to their superior stability, ease of fabrication, biocompatibility, controllable doping, and tunable bandgaps and excitons. In this review, we provide a systematic overview of the latest advancements in 2D TMDs SERS substrates. This review comprehensively summarizes the candidate 2D TMDs SERS materials, elucidates their working principles for SERS, explores the strategies to optimize their SERS performance, and highlights their practical applications. We particularly delve into the material engineering strategies, including defect engineering, alloy engineering, thickness engineering, and heterojunction engineering. Additionally, we discuss the challenges and future prospects associated with the development of 2D TMDs SERS substrates, outlining potential directions that may lead to significant breakthroughs in practical applications.

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Injectable scaffold delivery is a strategy to enhance the efficacy of cancer vaccine immunotherapy. The choice of scaffold biomaterial is crucial, impacting both vaccine release kinetics and immune stimulation via the host response. Extracellular matrix (ECM) scaffolds prepared from decellularized tissues facilitate a pro-healing inflammatory response that promotes local cancer immune surveillance. Here, we engineered an ECM scaffold-assisted therapeutic cancer vaccine that maintained an immune microenvironment consistent with tissue reconstruction. Several immune-stimulating adjuvants were screened to develop a cancer vaccine formulated with decellularized small intestinal submucosa ECM scaffold co-delivery. We found that the STING pathway agonist CDA most effectively induced cytotoxic immunity in an ECM scaffold vaccine, without compromising key IL-4 mediated immune pathways associated with healing. ECM scaffold delivery enhanced therapeutic vaccine efficacy, curing 50–75% of established EG.7 lymphoma tumors in mice, while none were cured with soluble vaccine. SIS-ECM scaffold-assisted vaccination prolonged antigen exposure, was dependent on CD8+ cytotoxic T cells, and generated long-term antigen-specific immune memory for at least 10 months post-vaccination. This study shows that an ECM scaffold is a promising delivery vehicle to enhance cancer vaccine efficacy while being orthogonal to characteristics of pro-healing immune hallmarks.

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Hollow multishelled structures (HoMS) have been attracting great interest in lithium-ion batteries as the conversion anodes, owing to their superior buffering effect and mechanical stability. Given the synthetic challenges, especially elemental diffusion barrier in the multi-metal combinations, this complex structure design has been realized in low- and medium-entropy compounds so far. It means that poor reaction reversibility and low intrinsic conductivity remain largely unresolved. Here, we develop a hollow multishelled (LiFeZnNiCoMn)3O4 high entropy oxide (HEO) through integrating molecule and microstructure engineering. As expected, the HoMS design exhibits significant targeting functionality, yielding satisfactory structure and cycling stability. Meanwhile, the abundant oxygen defects and optimized electronic structure of HEO accelerate the lithiation kinetics, while the retention of the parent lattice matrix enables reversible lithium storage, which is validated by rigorous in-situ tests and theoretical simulations. Benefiting from these combined properties, such hollow multishelled HEO anode can deliver a specific capacity of 967 mAh g−1 (89% capacity retention) after 500 cycles at 0.5 A g−1. The synergistic lattice and volume stability showcased in this work holds great promise in guiding the material innovations for the next-generation energy storage devices.

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