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Abstract Electrical stimulation holds promise for enhancing neuronal differentiation of neural stem cells to treat traumatic brain injury. However, once the stem cells leave the stimulating material and migrate post transplantation, electrical stimulation on them is diminished. Here, we wrap the stem cells with wireless electrical nanopatches, the conductive graphene nanosheets. Under electromagnetic induction, electrical stimulation can thus be applied in-situ to individual nanopatch-wrapped stem cells on demand, stimulating their neuronal differentiation through a MAPK/ERK signaling pathway. Consequently, 41% of the nanopatch-wrapped stem cells differentiate into functional neurons in 5 days, as opposed to only 16.3% of the unwrapped ones. The brain injury male mice implanted with the nanopatch-wrapped stem cells and exposed to a rotating magnetic field 30 min/day exhibit significant recovery of brain tissues, behaviors, and cognitions, within 28 days. This study opens up an avenue to individualized electrical stimulation of transplanted stem cells for treating neurodegenerative diseases.

Highlights Branch chain-rich diisopropyl ether (DIPE) was selected as co-solvent of low-temperature electrolyte for lithium metal battery. The introduction of DIPE improved the disorder of electrolyte and the branch chains from DIPE exclude other solvents from the Li+ solvent sheath, thereby achieving a rapid desolvation process. The electrolyte guaranteed a uniform Li stripping and deposition during cycling at both room temperature and low temperature and ensured stable cycling performance for Li||LFP cells over 650 cycles at − 20 °C.

Abstract Individual theranostic agents with dual-mode MRI responses and therapeutic efficacy have attracted extensive interest due to the real-time monitor and high effective treatment, which endow the providential treatment and avoid the repeated medication with side effects. However, it is difficult to achieve the integrated strategy of MRI and therapeutic drug due to complicated synthesis route, low efficiency and potential biosafety issues. In this study, novel self-assembled ultrasmall Fe3O4 nanoclusters were developed for tumor-targeted dual-mode T1/T2-weighted magnetic resonance imaging (MRI) guided synergetic chemodynamic therapy (CDT) and chemotherapy. The self-assembled ultrasmall Fe3O4 nanoclusters synthesized by facilely modifying ultrasmall Fe3O4 nanoparticles with 2,3-dimercaptosuccinic acid (DMSA) molecule possess long-term stability and mass production ability. The proposed ultrasmall Fe3O4 nanoclusters shows excellent dual-mode T1 and T2 MRI capacities as well as favorable CDT ability due to the appropriate size effect and the abundant Fe ion on the surface of ultrasmall Fe3O4 nanoclusters. After conjugation with the tumor targeting ligand Arg-Gly-Asp (RGD) and chemotherapy drug doxorubicin (Dox), the functionalized Fe3O4 nanoclusters achieve enhanced tumor accumulation and retention effects and synergetic CDT and chemotherapy function, which serve as a powerful integrated theranostic platform for cancer treatment.

Abstract Although stem cell therapy holds promise for the treatment of spinal cord injury (SCI), its practical applications are limited by the low degree of neural differentiation. Electrical stimulation is one of the most effective ways to promote the differentiation of stem cells into neurons, but conventional wired electrical stimulation may cause secondary injuries, inflammation, pain, and infection. Here, based on the high conductivity of graphite and the electromagnetic induction effect, graphite nanosheets with neural stem cells (NSCs) are proposed as an electromagnetic cellularized patch to generate in situ wirelessly pulsed electric signals under a rotating magnetic field for regulating neuronal differentiation of NSCs to treat SCI. The strength and frequency of the induced voltage can be controlled by adjusting the rotation speed of the magnetic field. The generated pulsed electrical signals promote the differentiation of NSCs into functional mature neurons and increase the proportion of neurons from 12.5% to 33.7%. When implanted in the subarachnoid region of the injured spinal cord, the electromagnetic cellularized patch improves the behavioral performance of the hind limbs and the repair of spinal cord tissue in SCI mice. This work opens a new avenue for remote treatment of SCI and other nervous system diseases.

Lithium metal‐graphene host composite is a promising anode material for high‐energy‐density Li battery owing to its three‐dimensional structure, micro‐level controllable thickness and ultrahigh specific capacity. However, we discover that the hydroxyl/carboxyl functional groups in the reduced graphene oxide (rGO) host are likely to be reduced into lithium carbonate composition in the solid‐electrolyte interphase (SEI), which resulted in severe lithium dendrite growth that deteriorate its electrochemical performances. Here, we develop a magnesium anchoring strategy that selectively bond the Mg ion with the hydroxyl/carboxyl groups in rGO host, generating an electrolyte‐derived lithium fluoride‐dominant SEI instead of oxygen groups‐derived, lithium carbonate‐dominant SEI. By anchoring 0.60% of Mg in the rGO host using a facile compositing‐pyrolysis approach, Li dendrite growth in anode can be significantly suppressed, and the cycling stability of Li metal full cells can be prolonged by 200%. These findings give new insight into the mechanism of SEI formation in Li metal anode, and provide a new design strategy for restraining the reduced reaction of hydroxyl/carboxyl groups in graphene to stabilize the composite anode of lithium metal battery.

Abstract Zinc oxide nanorods have been extensively studied for the specific killing of breast cancer (BC) cells, and their killing mechanism and anticancer effects have been initially demonstrated. However, systematic studies at the single‐cell level are still necessary to explore cellular functions in detail. In this work, a hydrothermal method was used to synthesize zinc oxide nanorod arrays (ZnO NRs). Their effect on BC cells was demonstrated at single‐cell resolution for the first time through microfluidic chips and a single‐cell analysis platform. The inhibitory effects of ZnO NRs were observed. First, ZnO NRs suppressed cell proliferation and migration abilities. Moreover, Interferon‐γ, Tumor Necrosis Factor‐α, and Granzyme B in BC cells turned out to be antitumor instead of tumorigenic under ZnO NRs stimulation. Furthermore, ZnO NRs inhibition altered cellular functions and thus weakened intercellular and intercluster correlations. More importantly, MDA‐MB‐231 cells (strongly metastatic) showed much greater resistance to ZnO NRs than MCF‐7 cells (nonmetastatic). The experiments complemented the findings at the single‐cell level and provided a more comprehensive consideration of the potential risks and applications of ZnO NRs in breast cancer therapy, which is of great importance for biomedical research on nanomaterials.

An effective fluorescent quencher with high quenching efficiency and good stability is of great significance for fluorescence sensing of biomolecules, such as nucleic acid. Here, a porphyrin-based covalent organic polymer (PCOP) was fabricated by a coupling reaction between 1,3,5-triethynylbenzene and 5,10,15,20-tetrakis(4′-bromophenyl) porphyrin. A stable water dispersed PCOP with a porous sphere-like morphology around 50 nm and a zeta potential of −24.6 mV was obtained by using the sonication method. The PCOP showed a superb quenching efficiency and fast quenching dynamics to fluorescent dye due to the high specific surface area of PCOP, which enables the π–π stacking of fluorescent dye to the conjugated porphyrin surface of PCOP, leading to a static quenching effect. The excellent property of PCOP as a fluorescent quencher is comparable with graphene oxide, which is widely utilized in biomolecule detection. Thus, a sensing platform of PCOP for the rapid fluorescence detection of DNA from influenza A virus was constructed with high sensitivity and selectivity. The detection range was found from 1 to 30 nM for the target DNA with a detection limit of 0.38 nM. The effective and stable dispersed nano-quencher reported here highlighted the importance of covalent organic polymers for their sensing application.

Abstract Osteoarthritis, a chronic degenerative cartilage disease, is the leading cause of movement disorders among humans. Although the specific pathogenesis and associated mechanisms remain unclear, oxidative stress‐induced metabolic imbalance in chondrocytes plays a crucial role in the occurrence and development of osteoarthritis. In this study, a trimanganese tetroxide (Mn3O4) nanozyme with superoxide dismutase (SOD)‐like and catalase (CAT)‐like activities is designed to reduce oxidative stress‐induced damage and its therapeutic effect is investigated. In vitro, Mn3O4 nanozymes are confirmed to reprogram both the imbalance of metabolism in chondrocytes and the uncontrolled inflammatory response stimulated by hydrogen peroxide. In vivo, a cross‐linked chondroitin sulfate (CS) hydrogel is designed as a substrate for Mn3O4 nanozymes to treat osteoarthritis in mouse models. As a result, even in the early stage of OA (4 weeks), the therapeutic effect of the Mn3O4@CS hydrogel is observed in both cartilage metabolism and inflammation. Moreover, the Mn3O4@CS hydrogel maintained its therapeutic effects for at least 7 days, thus revealing a broad scope for future clinical applications. In conclusion, these results suggest that the Mn3O4@CS hydrogel is a potentially effective therapeutic treatment for osteoarthritis, and a novel therapeutic strategy for osteoarthritis based on nanozymes is proposed.

Abstract Pre‐intercalation of metal ions into vanadium oxide is an effective strategy for optimizing the performance of rechargeable zinc‐ion battery (ZIB) cathodes. However, the battery long‐lifespan achievement and high‐capacity retention remain a challenge. Increasing the electronic conductivity while simultaneously prompting the cathode diffusion kinetics can improve ZIB electrochemical performance. Herein, N‐doped vanadium oxide (N‐(Zn,en)VO) via defect engineering is reported as cathode for aqueous ZIBs. Positron annihilation and electron paramagnetic resonance clearly indicate oxygen vacancies in the material. Density functional theory (DFT) calculations show that N‐doping and oxygen vacancies concurrently increase the electronic conductivity and accelerate the diffusion kinetics of zinc ions. Moreover, the presence of oxygen vacancies substantially increases the storage sites of zinc ions. Therefore, N‐(Zn,en)VO exhibits excellent electrochemical performance, including a peak capacity of 420.5 mA h g−1 at 0.05 A g−1, a high power density of more than 10 000 W kg−1 at 65.3 Wh kg−1, and a long cycle life at 5 A g−1 (4500 cycles without capacity decay). The methodology adopted in our study can be applied to other cathodic materials to improve their performance and extend their practical applications.

Biomass-derived porous carbon has gained significant attention as a cost-effective and sustainable material in non-noble metal carbon-based electrocatalysts for the oxygen reduction reaction (ORR). However, during the preparation of transition metal catalysts based on biomass-derived porous carbon, the agglomeration of transition metal atoms often occurs, leading to a notable decline in catalytic activity. In this study, we present a straightforward synthetic approach for the preparation of nitrogen-enriched soybean-derived porous carbon (Co@SP-C-a) as an electrocatalyst for the ORR. To achieve this, we employed a two-step method. In the first step, a chemical activator (KCl) was utilized to enhance the porosity of the self-doped nitrogen biomass carbon material. In the second step, a constant pressure drop funnel technique was employed to uniformly disperse bimetal cobalt/zinc-based zeolitic imidazolium frameworks (ZIF-L and ZIF-67) containing different metal ions (Zn2+ and Co2+) into the activated biomass carbon material. Subsequent high-temperature calcination of the ZIF-L and ZIF-67@SP-C-a composite precursor yielded the Co@SP-C-a catalyst. The obtained catalyst exhibited remarkable ORR activity in an alkaline solution (Eonset = 0.89 V, E1/2 = 0.83 V, JL = −6.13 mA·cm−2) and exceptional long-term stability. This study presents an effective strategy to prevent the agglomeration of metal nanoparticles when integrating them with biomass-based carbon materials, thus leading to enhanced catalytic performance.

Abstract Glioblastoma (GBM) is one of the most fatal central nervous system tumors and lacks effective or sufficient therapies. Ferroptosis is a newly discovered method of programmed cell death and opens a new direction for GBM treatment. However, poor blood–brain barrier (BBB) penetration, reduced tumor targeting ability, and potential compensatory mechanisms hinder the effectiveness of ferroptosis agents during GBM treatment. Here, a novel composite therapeutic platform combining the magnetic targeting features and drug delivery properties of magnetic nanoparticles with the BBB penetration abilities and siRNA encapsulation properties of engineered exosomes for GBM therapy is presented. This platform can be enriched in the brain under local magnetic localization and angiopep‐2 peptide‐modified engineered exosomes can trigger transcytosis, allowing the particles to cross the BBB and target GBM cells by recognizing the LRP‐1 receptor. Synergistic ferroptosis therapy of GBM is achieved by the combined triple actions of the disintegration of dihydroorotate dehydrogenase and the glutathione peroxidase 4 ferroptosis defense axis with Fe3O4 nanoparticle‐mediated Fe2+ release. Thus, the present findings show that this system can serve as a promising platform for the treatment of glioblastoma.

Photonics: Enabling new applications in optical communication and quantum technologies A review of recent progress in the microstructure and domain engineering of lithium niobate film on insulator (LNOI) has concluded that it is a promising photonic material for developing integrated nonlinear photonic devices. The review, conducted by a team of researchers from China and led by Hong Liu from Shandong University, found that the high-performance electro-optic and nonlinear optical properties of LNOI makes it an ideal platform for integrated photonics. Furthermore, they also discovered that the microstructures could be constructed on LNOI platforms for photonic circuits using current manufacturing techniques such as complementary metal–oxide–semiconductor technology. The researchers concluded that the large-scale and low-cost manufacturing of integrated photonic devices and systems by mature manufacturing processes could lead to the development of new applications in optical communication and quantum technologies.

Abstract The pioneering exfoliation of monolayer tungsten diselenide has greatly inspired researchers toward semiconducting applications. WSe2 belongs to a family of transition‐metal dichalcogenides. Similar to graphene, WSe2 and analogous dichalcogenides have layered structures with weak van der Waals interactions between two adjacent layers. First, the readers are presented with the fundamentals of WSe2, such as types, morphologies, and properties. Here, we report the characterization principles and practices such as microscopy, spectroscopy, and diffraction. Second, the methods for obtaining high‐quality WSe2, such as exfoliation, hydrothermal and chemical vapor deposition, are briefly listed. With advantages of light weight, flexibility, and high quantum efficiency, 2D materials may have a niche in optoelectronics as building blocks in p‐n junctions. Therefore, we introduce a state‐of‐the‐art demonstration of heterostructure devices employing the p‐type WSe2 semiconductor. The device architectures include field‐effect transistors, photodetectors, gas sensors, and photovoltaic solar cells. Due to its unique electronic, optical, and energy band properties, WSe2 has been increasingly investigated due to the conductivity of the p‐type charge carrier upon palladium contact. Eventually, the dynamic research on WSe2 and van der Waals heterostructures is summarized to arouse the passion of the 2D research community.

Silicon-derived biomaterials are conducive to regulating the fate of osteo-related stem cells, while their effects on the osteogenic differentiation of human adipose-derived stem cells (hADSCs) remain inconclusive. Mesoporous silica (mSiO2) is synthesized in a facile route that exhibited the capability of promoting osteogenic differentiation of hADSCs. The metabolism of SiO2 in cells is proposed according to the colocalization fluorescence analysis between lysosomes and nanoparticles. The released silicon elements promote osteogenic differentiation. The detection of secretory proteins through numerous parallel experiments performed via a microfluidic chip confirms the positive effect of SiO2 on the osteogenic differentiation of hADSCs. Moreover, constructed with superparamagnetic iron oxide (Fe3O4), the magnetic nanoparticles (MNPs) of Fe3O4@mSiO2 endow the cells with magnetic resonance imaging (MRI) properties. The MNP-regulated osteogenic differentiation of autologous adipose-derived stem cells provides considerable clinical application prospects for stem cell therapy of bone tissue repair with an effective reduction in immune rejection.

Cancellous bone plays an indispensable role in the skeletal system due to its various functions and high porosity. In this work, chitosan and hydroxyapatite nanowires (CS@HAP NWs) hybrid nanostructured scaffolds with suitable mechanical properties, high porosity and a fine porous structure were prepared to simulate the 3-dimensional structure of cancellous bone. The 3D-hybrid scaffolds promote cell adhesion and the migration of human adipose-derived stem cells (hADSCs) inside the scaffolds. The cavities in the scaffolds provide space for the hADSCs proliferation and differentiation. Moreover, the various contents of HAP and the induced mechanical property changes regulate the differentiation of hADSCs toward osteoblasts. Overall, cellular fate regulation of hADSCs via rationally engineered HAP-based hybrid scaffolds is a facile and effective approach for bone tissue engineering.

Abstract Rechargeable aqueous zinc‐ion batteries (ZIBs) have recently been comprehensively studied because of metal zinc (Zn) unique properties. However, the problems of metal zinc anode in ZIBs, namely, dendrite formation and side reactions, seriously shorten the cycling lifetimes and limit the coulombic efficiencies. Here, the tin (Sn) layer with a three‐dimensional nano‐channeled structure is decorated on zinc metal via a facile in situ substitution reaction, constructing the Sn modified Zn (Sn‐Zn) anode for high‐performance ZIBs. Multiscale investigation techniques, especially micro‐CT, are used to investigate the inhibition of zinc dendrites. In addition, the induction mechanism of Zn by Sn is also elaborately investigated. The designed Sn‐Zn anode can alleviate zinc dendrite growth and ensure long‐life stability. This work brings exciting new possibilities for the realization of industrial aqueous zinc‐ion batteries and provides new insights for the rational deposition of the Zn metal anodes.

Abstract Proinflammatory (M1) macrophages play a vital role in antitumor immunity, and regulation of proinflammatory macrophage polarization is critical for immunotherapy. The polarization of macrophages can be regulated by biological or chemical stimulation, but investigations of the regulatory effect of physical stimulation are limited. Herein, regulating macrophage polarization with localized electrical signals derived from a piezoelectric β‐phase poly(vinylidene fluoride) (β‐PVDF) film in a wireless mode is proposed. Charges released on the surface of the β‐PVDF film driven by ultrasonic irradiation can significantly enhance the M1 polarization of macrophages. Mechanistic investigation confirms that electrical potentials rather than reactive oxygen species and mechanical forces enable Ca2+ influx through voltage‐gated channels and establishment of the Ca2+‐CAMK2A‐NF‐κB axis to promote the proinflammatory macrophage response during ultrasound treatment. Piezoelectric material‐mediated electrical signal‐activated proinflammatory macrophages significantly inhibit tumor cell proliferation. A method for electrogenetic regulation of immune cells as well as a powerful tool for engineering macrophages for immunotherapy is provided here.

A piezoelectric field promotes the photocatalytic activity of a photocatalyst by helping separating photo-generated charge carriers. Wurtzite phase ZnO is a typical photocatalyst with a piezoelectric property, thus self-assisted photocatalysis with ZnO based on the piezophototronic effect can be achieved. ZnO nanorods or nanowires with a clear c-axis have been well studied, while other morphologies have not been fully discussed. In this work, we prepared wurtzite phase ZnO with four different morphologies. By comparing their photocatalytic activity for degradation of Rhodamine B under the same mechanical energy source provided by ultrasound, the effect of morphology and exposed facets on photo-induced charge separation were highlighted. The ZnO nanowire photocatalyst delivered an impressive improvement in photocatalytic efficiency when ultrasound driven, suggesting that the morphology-related piezophototronic effect had a positive effect on separation of photo-generated charge carriers, and more exposed active facets benefitted the utilization of charge carriers.

Abstract Water splitting for production of hydrogen as a clean energy alternative to fossil fuel has received much attention, but it is still a tough challenge to synthesize electrocatalysts with controllable bonding and charge distribution. In this work, ultrafine S‐doped RuP nanoparticles homogeneously embedded in a N, P, and S‐codoped carbon sheet (S‐RuP@NPSC) is synthesized by pyrolysis of poly(cyclotriphosphazene‐co‐4,4′‐sulfonyldiphenol) (PZS) as the source of C/N/S/P. The bondings between Ru and N, P, S in PZS are regulated to synthesize RuS2 (800 °C) and S‐RuP (900 °C) by different calcination temperatures. The S‐RuP@NPSC with low Ru loading of 0.8 wt% with abundant active catalytic sites possesses high utilization of Ru, the mass catalytic activity is 22.88 times than 20 wt% Pt/C with the overpotential of 250 mV. Density functional theory calculation confirms that the surface Ru (−0.18 eV) and P (0.05 eV) are catalytic active sites for the hydrogen evolution reaction (HER), and the according charge redistribution of Ru is regulated by S and P with reverse electronegativity and electron–donor property to induce a synergistically enhanced reactivity toward the HER. This work provides a rational method to regulate the bonding and charge distribution of Ru‐based electrocatalysts by reacting macromolecules with multielement of C/N/S/P with Ru.

Abstract Rechargeable aqueous zinc‐ion batteries (ZIBs) show promise for use in energy storage. However, the development of ZIBs has been plagued by the limited cathode candidates, which usually show low capacity or poor cycling performance. Here, a reversible Zn//(Na,Mn)V8O20·nH2O system is reported, the introduction of manganese (Mn) ions in NaV8O20 to form (Na,Mn)V8O20 exhibits an outstanding electrochemical performance with a capacity of 377 mA h g−1 at a current density of 0.1 A g−1. Through experimental and theoretical results, it is discovered that the outstanding performance of (Na,Mn)V8O20·nH2O is ascribed to the Mn2+/Mn3+‐induced high electrical conductivity and Na+‐induced fast migration of Zn2+. Other cathode materials derived from (Na,Mn)V8O20·nH2O by substituting Mn with Fe, Co, Ni, Ca, and K are explored to confirm the unique advantages of transition metal ions. With an increase in Mn content in NaV8O20, (Na0.33,Mn0.65)V8O20 ·nH2O can deliver a reversible capacity of 150 mA h g−1 and a capacity retention of 99% after 1000 cycles, which may open new opportunities for the development of high‐performance aqueous ZIBs.

Abstract Suppressing the recombination of photogenerated charges is one of the most important routes for enhancing the catalytic performance of semiconductor photocatalysts. In addition to the built‐in field produced by semiconductor heterostructures and the photo‐electrocatalysis realized by applying an external electrical potential to photocatalysts assembled on electrodes, other strategies are waiting to be scientifically explored and understood. In this work, a Lorentz force–assisted charge carrier separation enhancement strategy is reported to improve the photocatalytic efficiency by applying a magnetic field to a photocatalytic system. The photocatalytic efficiency can be improved by 26% just by placing a permanent magnet beneath the normal photocatalytic system without any additional power supply. The mechanism by which the Lorentz force acts oppositely on the photogenerated electrons and holes is introduced, resulting in the suppression of the photoinduced charge recombination. This work provides insights into the specific role of the Lorentz force in suppressing the recombination of electron–hole pairs in their initial photogenerated states. This suppression would increase the population of charge carriers that would subsequently be transported in the semiconductor. It is believed that this strategy based on magnetic effects will initiate a new way of thinking about photoinduced charge separation.

Band structure engineering and heterojunction photocatalyst construction are efficient approaches to improve the separation of photo-induced electrons and holes, along with enhancing light response ability. By sulfur doping, sodium tantalite (NaTaO3) showed an improved photocatalytic property for the degradation of Rhodamine B (RhB). Sn3O4 nanoflakes were constructed on the surface of NaTaO3 nanocubes, forming a surface heterostructure via a simple hydrothermal process, initially. This heterostructure endows the photocatalyst with an enhanced charge separation rate, resulting in an improved photocatalytic degradation of RhB. Moreover, a possible mechanism over Sn3O4/NaTaO3 and the photodegradation pathway of RhB were proposed as the combined effect of photo-induced electrons and holes. This facile process for band structure engineering and heterostructure construction provides the possibility for the practical application of high-efficiency photocatalysts.