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Solid-state quantum emitters are gaining significant attention for many quantum information applications. Hexagonal boron nitride (h-BN) is an emerging host material for generating bright, stable, and tunable single-photon emission with narrow line widths at room temperature. In this work, we present a facile and efficient approach to generate high-density single-photon emitters (SPEs) in mechanically exfoliated h-BN through H- or Ar-plasma treatment followed by high-temperature annealing in air. It is notable that the postannealing is essential to suppress the fluorescence background in photoluminescence spectra and enhance emitter stability. These quantum emitters exhibit excellent optical properties, including high purity, brightness, stability, polarization degree, monochromaticity, and saturation intensity. The effects of process parameters on the quality of quantum emitters were systematic investigated. We find that there exists an optimal plasma power and h-BN thickness to achieve a high SPE density. This work offers a practical avenue for generating SPEs in h-BN and holds promise for future research and applications in quantum photonics.

Near-infrared light excitable triplet-triplet annihilation upconversion (NIR TTA-UC) materials have attracted interest in a variety of emerging applications such as photoredox catalysis, optogenetics, and stereoscopic 3D printing. Currently, the practical application of NIR TTA-UC materials requires substantial improvement in photostability. Here, we found that the new annihilator of π-expanded diketopyrrolopyrrole (π-DPP) cannot activate oxygen to generate superoxide anion via photoinduced electron transfer, and its electron-deficient characteristics prevent the singlet oxygen-mediated [2 + 2] cycloaddition reaction; thus, π-DPP exhibited superior resistance to photobleaching. In conjunction with the NIR photosensitizer PdTNP, the upconversion efficiency of π-DPP is as high as 8.9%, which is eight times of the previously reported PdPc/Furan-DPP. Importantly, after polystyrene film encapsulation, less than 10% photobleaching was observed for this PdTNP/π-DPP-based NIR TTA-UC material after four hours of intensive NIR light exposure. These findings provide a type of annihilator with extraordinary photostability, facilitating the development of NIR TTA-UC materials for practical photonics.

Stretchable hydrogels as landmark soft materials have been efficiently utilized in the field of wearable sensing devices. However, these soft hydrogels mostly cannot integrate transparency, stretchability, adhesiveness, self-healing, and environmental adaptability into one system. Herein, a fully physically cross-linked poly(hydroxyethyl acrylamide)-gelatin dual-network organohydrogel is prepared in a phytic acid-glycerol binary solvent via a rapid ultraviolet light initiation. The introduction of gelatin as the second network endows the organohydrogel with desirable mechanical performance (high stretchability up to 1240%). The presence of phytic acid not only synergizes with glycerol to impart environment-tolerance to the organohydrogel (from -20 to 60 °C) but also increases the conductivity. Moreover, the organohydrogel demonstrates a durable adhesive performance toward diverse substrates, a high self-healing efficiency through heat treatment, and favorable optical transparency (transmittance of 90%). Furthermore, the organohydrogel achieves high sensitivity (gauge factor of 2.18 at 100% strain) and rapid response time (80 ms) and could detect both tiny (a low detection limit of 0.25% strain) and large deformations. Therefore, the assembled organohydrogel-based wearable sensors are capable of monitoring human joint motions, facial expression, and voice signals. This work proposes a facile route for multifunctional organohydrogel transducers and promises the practical application of flexible wearable electronics in complex scenarios.

Currently, healing of large bone defects faces significant challenges such as a bulk of bone regeneration and revascularization on the bone defect region. Here, a "cell-free scaffold engineering" strategy that integrates strontium (Sr) and highly bioactive serum exosomes (sEXOs) inside a three-dimensional (3D)-printed titanium (Ti) scaffold (Sc) is first developed. The constructed SrTi Sc can serve as a sophisticated biomaterial platform for maintaining bone morphological characteristics of the radius during the period of critical bone defect (CBD) repair and further accelerating bone formation and fibroblastic suppression via the controlled release of Sr from the superficial layer of the scaffold. Moreover, compared with sEXO from healthy donors, the sEXO extracted from the serum of the femoral fracture rabbit model at the stage of fracture healing, named BF EXO, is robustly capable of facilitating osteogenesis and angiogenesis. In addition, the underlying therapeutic mechanism is elucidated, whereby altering miRNAs shuttled by BF EXO enables osteogenesis and angiogenesis. Further, the in vivo study revealed that the SrTi Sc + BF EXO composite dramatically accelerated bone repair via osteoconduction, osteoinduction, and revascularization in radial CBD of rabbits. This study broadens the source and biomedical potential of specifically functionalized exosomes and provides a comprehensive clinically feasible strategy for therapeutics on large bone defects.

Conventional chemotherapy usually fails to achieve its intended effect because of the poor water solubility, poor tumor selectivity, and low tumor accumulation of chemotherapy drugs. The systemic toxicity of chemotherapy agents is also a problem that cannot be ignored. It is expected that smart nano-drug delivery systems that are able to respond to tumor microenvironments will provide better therapeutic outcomes with decreased side effects of chemotherapeutics. Nano-drug delivery systems capable of breaking the redox balance can also increase the sensitivity of tumor cells to chemotherapeutics. In this study, using polymer-containing disulfide bonds, ester bonds, and d-α-tocopherol polyethylene glycol succinate (TPGS), which can amplify reactive oxygen species (ROS) in tumor cells, we have successfully prepared a smart glutathione (GSH) and esterase dual-responsive nano-drug delivery system (DTX@PAMBE-SS-TPGS NPs) with the ability to deplete GSH as well as amplify ROS and effectively release an encapsulated chemotherapy drug (DTX) in tumor cells. The potential of DTX@PAMBE-SS-TPGS NPs for enhanced antitumor effects was thoroughly evaluated using in vitro as well as in vivo experiments. Our research offers a promising strategy for maximizing the efficacy of tumor therapy.

A heterogeneous interface usually plays a versatile role in modulating catalysis and the durability of hybrid electrocatalysts for oxygen evolution reaction (OER), and its intrinsic mechanism is still in dispute due to an uncertain correlation of initial, intermediate and active phases. In this article, the CoMoO 4 ·0.69H 2 O/Co 3 O 4 heterogeneous interface is configured to understand the evolution kinetics of these correlated phases. Due to the chemically and electrochemically "inert" character of Co 3 O 4 support, lattice strain with 3.31% tuning magnitude in primary CoMoO 4 ·0.69H 2 O can be inherited after spontaneous dissolution of molybdenum cations in electrolyte, dominating catalytic activity of the reconstructed CoOOH. In situ Raman spectroscopy demonstrates reversible conversion between active CoOOH and amorphous cobalt oxide during OER when positive and negative potentials are sequentially supplied onto hybrid catalysts with favorable strain. Therefore, superior durability with negligible decay after 10 cycles is experimentally identified for intermittent oxygen evolution. Theoretical calculations indicate that appropriate stress within the electrocatalyst could reduce the reaction energy barrier and enhance the OER performance by optimizing the adsorption of intermediates.

Two-dimensional (2D) transition-metal dichalcogenides (TMDs) exhibit promising potential in fabricating highly sensitive photodetectors due to their unique electrical and optoelectrical characteristics. However, micron-sized 2D materials produced by conventional chemical vapor deposition (CVD) and mechanical exfoliation methods fail to satisfy the demands for applications in integrated optoelectronics and systems given their poor controllability and repeatability. Here, we propose a simple selenization approach to grow wafer-scale (2 in.) 2D p -WSe 2 layers with high uniformity and customized patterns. Furthermore, a self-driven broadband photodetector with a p -WSe 2 / n -Si van der Waals heterojunction has been in situ fabricated with a satisfactory responsivity of 689.8 mA/W and a large specific detectivity of 1.59 × 10 13 Jones covering from ultraviolet to short-wave infrared. In addition, a remarkable nanosecond response speed has been recorded under 0.5% duty cycle of the input light. The proposed selenization approach on the growth of 2D WSe 2 layers demonstrates an effective route to fabricate highly sensitive broadband photodetectors used for integrated optoelectronic systems.

Voltage reversal of proton exchange membrane fuel cells caused by hydrogen deficiency seriously deteriorates the anodes and lowers their performance and lifetime. A commonly used method is to add oxygen evolution reaction catalysts (e.g., IrO 2 ) to the anode to extend the water electrolysis plateau against harmful carbon corrosion. Herein, strongly connected IrO x nanoparticles (SC-IrO x ) are prepared by removing the low surface area carbon carrier of the as-synthesized Ir/C catalyst. The reversal-tolerant anode with SC-IrO x owns an anti-reversal time of 9.32 h, which is 3.2 and 4.4 times that of the reversal-tolerant anode with commercial IrO x and weakly connected IrO x , respectively. Further transmission electron microscope characterizations reveal that SC-IrO x can construct a stable electron and proton transport pathway in the anode catalyst layer, which can delay the isolation of oxygen evolution reaction catalyst from the electron and proton conducting network, thus extending the water electrolysis plateau. Herein, our findings suggest that tuning the microstructures of IrO x catalysts is indeed an effective and promising approach to extend the water electrolysis plateau and alleviate the performance degradation of proton exchange membrane fuel cells during the voltage reversal process.

Tumor microenvironment (TME) responsive chemodynamic therapy (CDT) showed an important application in inhibiting tumor growth by producing the highly toxic hydroxyl radical (·OH), but insufficient hydrogen peroxide (H 2 O 2 ) and overexpressed glutathione (GSH) limited its application. Herein, by integrating photothermal therapy (PTT) and CDT, a new kind of mesoporous polydopamine (MPDA)-based cascade-reaction nanoplatform (MPDA@AuNPs-Cu) was designed for enhanced antitumor therapy, in which ultrasmall gold nanoparticles (AuNPs) with glucose oxidase (GOx)-like activity were deposited on MPDA for providing H 2 O 2 , and Cu 2+ was chelated for GSH-responsive Fenton-like reaction. It was demonstrated that the MPDA@AuNPs-Cu nanoprobe showed high photothermal conversion efficiency and excellent biocompatibility. Moreover, the MPDA@AuNPs-Cu nanoprobe exhibited strong ·OH generation because of H 2 O 2 self-generation and photothermal stimulation. Importantly, compared with MPDA-Cu, MPDA@AuNPs-Cu exhibited enhanced in vitro and in vivo CDT/PTT performance, by which the tumor growth was completely inhibited, achieving TME-responsive antitumor efficacy.

Broadband near-infrared (NIR) phosphors are in high demand for creating "smart" NIR phosphor-converted light-emitting diode (pc-LED) sources. In this work, a series of Cr 3+ -substituted NIR-emitting materials with highly efficient, broad, tunable emission spectra are achieved by modifying the simple oxide Ga 2 O 3 using [Mg 2+ -Ge 4+ ] and [Ga 3+ -Ga 3+ ] co-unit substitution. The results show that the emission peak can be shifted from 726 to 830 nm while maintaining a constant excitation peak in the blue light region, enabling extensive application. The optical properties stem from changes in the Cr 3+ crystal field environment upon substitution. Intriguingly, the temperature-dependent photoluminescence emission peak position shows virtually no change in the [Mg 2+ -Ge 4+ ] co-substituted materials. This abnormal phenomenon is found to be a comprehensive embodiment of a weakening crystal field environment (red-shift) as the temperature increases and reduced local structure distortion (blue-shift) with increasing temperature. The high quantum yield, NIR emission, and net-zero emission shift as a function of temperature make this phosphor class optimal for device incorporation. As a result, their performance was studied by coating the phosphor on a 450 nm emitting LED chip. The fabricated device demonstrates an excellent NIR output power and NIR photoelectric conversion efficiency. This study provides a series of efficient, tunable, broadband NIR materials for spectroscopy applications and contributes to the basic foundation of Cr 3+ -activated NIR phosphors.

To address the urgent demand for sensitive and stable detection applications, significant efforts have been made in the development of dual-signal readout assays for precise target detection and timely health risk control. Here, a new nanomaterial, Pt@PCN-224-HRP-initiator DNA (PP-HRP-iDNA), was exploited to construct a dual-signal readout biosensing platform. Zr-MOF (PCN-224) was loaded with as many Pt nanoparticles (NPs) and as much horseradish peroxidase (HRP) as possible to enhance the brightness of the colorimetric signal recognizable to the naked eye while also acting as a gatekeeper to protect the enzyme activity and ensuring the stability of the assay process. Moreover, the Pt NPs and HRP displayed a synergistic catalytic effect, which promoted the sensitivity of detection. Further, the formation of the Zr- O -P bond eliminated the instability of the interactions between PCN-224 and iDNA in a controllable manner. After the immunoreaction, iDNA stimulated a hybridization chain reaction, resulting in a significant reduction of the fluorescent DNA in the supernatant and a fluorescent signal change. Subsequently, the PP-HRP-iDNA probe implemented UV-light response (450 nm) where 3,3',5,5'-tetramethylbenzidine was used as a substrate for the colorimetric signal readout. By virtue of the nanomaterial-modulated transduction mechanism and the antigen-antibody interactions, this dual-signal biosensor displays high sensitivity, with a limit of detection of 0.65 pg/mL for aflatoxin B 1 and 4 CFU/mL for Salmonella enteritidis , suggesting the detection potential of the biosensing platform for analyzing various targets.

We demonstrate the use of the machine learning (ML) tools to rapidly and accurately predict the electric field as a guide for designing core-shell Au-silica nanoparticles to enhance 1 O 2 sensitization and selectivity of organic synthesis. Based on the feature importance analysis, obtained from a deep neural network algorithm, we found a general and linear dependent descriptor (θ ∝ aD 0.25 t -1 , where a , D , and t are the shape constant, size of metal nanoparticles, and distance from the metal surface) for the electric field around the core-shell plasmonic nanoparticle. Directed by the new descriptor, we synthesized gold-silica nanoparticles and validated their plasmonic intensity using scanning transmission electron microscopy-electron energy loss spectroscopy (STEM-EELS) mapping. The nanoparticles with θ = 0.40 demonstrate an ∼3-fold increase in the reaction rate of photooxygenation of anthracene and 4% increase in the selectivity of photooxygenation of dihydroartemisinic acid (DHAA), a long-standing goal in organic synthesis. In addition, the combination of ML and experimental investigations shows the synergetic effect of plasmonic enhancement and fluorescence quenching, leading to enhancement for 1 O 2 generation. Our results from time-dependent density functional theory (TD-DFT) calculations suggest that the presence of an electric field can favor intersystem crossing (ISC) of methylene blue to enhance 1 O 2 generation. The strategy reported here provides a data-driven catalyst preparation method that can significantly reduce experimental cost while paving the way for designing photocatalysts for organic drug synthesis.

3D-printed porous tantalum scaffold has been increasingly used in arthroplasty due to its bone-matching elastic modulus and good osteoinductive ability. However, the lack of antibacterial ability makes it difficult for tantalum to prevent the occurrence and development of periprosthetic joint infection. The difficulty and high cost of curing periprosthetic joint infection (PJI) and revision surgery limit the further clinical application of tantalum. Therefore, we fabricated vancomycin-loaded porous tantalum scaffolds by combining the chemical grafting of (3-aminopropyl)triethoxysilane (APTES) and the electrostatic assembly of carboxymethyl chitosan and vancomycin for the first time. Our in vitro experiments show that the scaffold achieves rapid killing of initially adherent bacteria and effectively prevents biofilm formation. In addition, our modification preserves the original excellent structure and biocompatibility of porous tantalum and promotes the generation of mineralized matrix and osteogenesis-related gene expression by mesenchymal stem cells on the surface of scaffolds. Through a rat subcutaneous infection model, the composite bioscaffold shows efficient bacterial clearance and inflammation control in soft tissue and creates an immune microenvironment suitable for tissue repair at an early stage. Combined with the economic friendliness and practicality of its preparation, this scaffold has great clinical application potential in the treatment of periprosthetic joint infection.

Because of their high ionic conductivity, utilizing gel polymer electrolytes (GPEs) is thought to be an effective way to accomplish high-energy-density batteries. Nevertheless, most GPEs have poor adaptability to Ni-rich cathodes to alleviate the problem of inevitable rapid capacity decay during cycling. Therefore, to match LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811), we applied pentaerythritol tetraacrylate (PETEA) monomers to polymerize in situ in a polyacrylonitrile (PAN) membrane to obtain GPEs (PETEA-TCGG-PAN). The impedance variations and key groups during the in situ polymerization of PETEA-TCGG-PAN are investigated in detail. PETEA-TCGG-PAN with a high lithium-ion transference number (0.77) exhibits an electrochemical decomposition voltage of 5.15 V. Noticeably, the NCM811|PETEA-TCGG-PAN|Li battery can cycle at 2 C for 120 cycles with a capacity retention rate of 89%. Even at 6 C , the discharge specific capacity is able to reach 101.47 mAh g -1 . The combination of LiF and Li 2 CO 3 at the CEI interface is the reason for the improved rate performance. Moreover, when commercialized LFP is used as the cathode, the battery can also cycle stably for 150 cycles at 0.5 C . PETEA and PAN can together foster the transportation of Li + with the construction of a fast ion transport channel, making a contribution to stable charge-discharge of the above batteries. This study provides an innovative design philosophy for designing in situ GPEs in high-energy-density lithium metal batteries.

Combining black silicon (BS), a nanostructured silicon containing highly roughened surface morphology with plasmonic materials, is becoming an attractive approach for greatly enhancing light-matter interactions with promising applications of sensing and light harvesting. However, precisely describing the optical response of a heavily decorated BS structure is still challenging due to the increasing complexity in surface morphology and plasmon hybridization. Here, we propose and fully characterize BS-based multistacked nanostructures with randomly distributed nanoparticles on the highly roughened nonflat surface. We demonstrate a realistic 3D modeling methodology based on parametrized scanning electron microscopy images that provides high-precision morphology details, successfully linking the theoretical analysis with experimental optical response of the complex nanostructures. Far-field calculations very nicely reproduce experimental reflectance spectra, revealing the dependency of light trapping on the thickness of the conformal reflector and the atop nanoparticle size. Near-field analysis clearly identifies three types of stochastic "hotspots". Their contribution to the overall field enhancement is shown to be very much sensitive to the nanoscale surface morphology. The simulated near-field property is then used to examine the measured surface-enhanced Raman scattering (SERS) response on the multistacked structures. The present modeling approach combined with spectroscopic characterizations is expected to offer a powerful tool for the precise description of the optical response of other large-scale highly disordered realistic 3D systems.

To overcome the low efficacy of conventional monotherapeutic approaches that use a single drug, functional nanocarriers loaded with an amalgamation of anticancer drugs have been promising in cancer therapy. Herein, aloe-derived nanovesicles (gADNVs) are modified with an active integrin-targeted peptide (Arg-Gly-Asp, RGD) by the postinsertion technique to deliver indocyanine green (ICG) and doxorubicin (DOX) for efficient breast cancer therapy. We presented for the first time that the π-π stacking interaction can turn the "competitive" relationship of ICG and DOX inside gADNVs into a "cooperative" relationship and enhance their loading efficiency. The dual-drug codelivery nanosystem, denoted as DIARs, was well stable and leakproof, exhibiting high tumor-targeting capability both in vitro and in vivo . Meanwhile, this nanosystem showed significant inhibition of cell growth and migration and induced cell apoptosis with the combination of phototherapy and chemotherapy. Intravenous administration of DIARs exhibited high therapeutic efficacy in a 4T1 tumor-bearing mouse model and exhibited no obvious damage to other organs. Overall, our DIAR nanosystem constitutively integrated the natural and economical gADNVs, π-π stacking interaction based on efficient drug loading, and tumor-targeted RGD modification to achieve an effective combination therapy for breast cancer.

3D-printed porous bioactive ceramic scaffolds have been widely used in bone defect repair. However, material implantation is often accompanied by a foreign body response (FBR), which may affect host tissue regeneration. The physical properties of biomaterials, including shape, pore size, and porosity, control the relevant immune responses during tissue regeneration. To the best of our knowledge, the effect of the pore size of 3D-printed scaffolds on the immune response and bone-biomaterial integration has not been studied in vivo. Polycaprolactone/polyethylene glycol/hydroxyapatite (PCL/PEG/HA) bioactive scaffolds with different pore sizes, including 209.9 ± 77.1 μm (P200), 385.5 ± 28.6 μm (P400), and 582.1 ± 27.2 μm (P600), were prepared with a pneumatic extrusion 3D printer. Compared with other pore sizes, P600 significantly reduced the FBR and induced more M2 macrophage infiltration, vascular ingrowth, and new bone formation. Immunohistochemical staining revealed that the MyD88 protein might be involved in macrophage polarization-related signal transduction in response to the pore size. Based on these results, bone regeneration requires the active participation of the immune response, and the P600 PCL/PEG/HA scaffold is a preferable candidate for the repair of bone defects.

The classical high-temperature synthesis process of Cu(In,Ga)Se 2 (CIGS) solar cells limits their applications on high-temperature intolerant substrates. In this study, a novel low-temperature (400 °C) fabrication strategy of CIGS solar cells is reported using the bismuth (Bi)-doping method, and its growth-promoting mechanism is systematically studied. Different concentrations of Bi are incorporated into pure chalcopyrite quaternary target sputtered-CIGS films by controlling the thickness of the Bi layer. Bi induces considerable grain growth improvement, and an average of approximately 3% absolute efficiency enhancement is achieved for Bi-doped solar cells in comparison with the Bi-free samples. Solar cells doped with a 50 nm Bi layer yield the highest efficiency of 13.04% (without any antireflective coating) using the low-temperature technology. The copper-bismuth-selenium compounds (Cu-Bi-Se, mainly Cu 1.6 Bi 4.8 Se 8 ) are crucial in improving the crystallinity of absorbers during the annealing process. These Bi-containing compounds are conclusively observed at the grain boundaries and top and bottom interfaces of CIGS films. The growth promotion is found to be associated with the superior diffusion capacity of Cu-Bi-Se compounds in CIGS films, and these liquid compounds function as carriers to facilitate crystallization. Bi atoms do not enter the CIGS lattices, and the band gaps ( E g ) of absorbers remain unchanged. Bi doping reduces the number of CIGS grain boundaries and increases the copper vacancy content in CIGS films, thereby boosting the carrier concentrations. Cu-Bi-Se compounds in grain boundaries significantly enhance the conductivity of grain boundaries and serve as channels for carrier transport. The valence band, Fermi energy level ( E F ), and conduction band of Bi-doped CIGS films all move downward. This band shift strengthens the band bending of the CdS/CIGS heterojunction and eventually improves the open circuit voltage ( V oc ) of solar cells. An effective doping method and a novel mechanism can facilitate the low-temperature preparation of CIGS solar cells.

In modern electronic and power systems, it is essential to develop advanced dielectric materials with high energy density. One-dimensional ferroelectric ceramic nanofibers were proved to be a feasible strategy for improving the permittivity and energy density of nanocomposites. In this paper, to overcome the high loss issue of Na 0.5 Bi 0.5 TiO 3 (NBT), a kind of novel nanofibers 0.93Na 0.5 Bi 0.5 TiO 3 -0.07BaTiO 3 (NBT-BT) with large aspect ratio are synthesized by the electrospinning method and used as the dielectric fillers in trilayer structured poly(vinylidene difluoride) (PVDF) nanocomposites for energy storage applications. The finite element analysis is performed to evaluate the electric field distribution in the nanocomposites. The results showed that the trilayer structured nanocomposite loaded with 6 wt % NBT-BT nanofibers in the middle layer achieved the highest discharge energy density of 19.21 J cm -3 at 527 kV mm -1 , which is 87.2% higher than that of pure PVDF (10.26 J cm -3 at 420 kV mm -1 ). Owing to the contribution of the barrier effect and interface polarization between adjacent layers, the energy density of the trilayer structured nanocomposites is significantly higher than that of the single-layer nanocomposites. This work provides a kind of novel one-dimensional ceramic fillers for obviously improving the energy density of polymer-based dielectrics.

Plant bacterial diseases are serious problems in agriculture, posing threats to global food security and the agricultural economy. Here, a degradable agricultural bactericide AMC-10 constructed using a charge-reversal surfactant, from being positively charged to negatively charged, was designed and synthesized. AMC-10 possessed high bactericidal activity toward plant pathogenic bacteria, consequently being able to inhibit the corresponding plant bacterial diseases. After degradation by water, the hydrolyzed products were nontoxic to bacteria and human cells. Such a degradable bactericide provides new ideas for the design of environmentally friendly agricultural bactericides. It is anticipated that degradable bactericides such as AMC-10 can be applied in the prevention and control of plant bacterial diseases, being less likely to produce toxicity or drug resistance.

Seeking fast proton transport pathways at ambient conditions is desirable but challenging. Here, we report a strategy to synthesize a composite material with a polyoxometalate (POM) and an ionic liquid (IL) confined in stable metal-organic framework (MOF) channels through electrostatic interaction. The obtained SO 3 H-IL-PMo 12 @MIL-101 possesses fast proton transfer, and its proton conductivity can reach 1.33 × 10 -2 S cm -1 at ambient conditions (30 °C, 70% relative humidity (RH)), which is the highest value among the MOF-based proton conductors operated in an ambient environment. Therefore, it has the potential of becoming a room-temperature proton conductor without a humidifier. Importantly, the composite material is further fabricated into a composite membrane for proton-exchange membrane fuel cells (PEMFCs), which can deliver a power density of 0.93 mW cm -2 at 30 °C and 98% RH. This result can lay a fundamental basis for the application of MOF-based proton conductors in the area of electrochemical energy conversion.

Anthraquinone (AQ) as an effective hydrogen atom transfer catalyst was limited in photocatalysis application due to the dimerization of reduced AQ. Sr-NDI@AQ, encapsulating AQ into the channel of Sr-NDI, paved a new way for solving the problem of dimerization of reduced AQ and improving the catalytic efficiency owing to the fast electron transfer from reduced AQ to the ligand through host-guest interaction. The structure of Sr-NDI@AQ was determined by single-crystal X-ray diffraction, and the value for distance and torsion angle between the ligand and AQ was calculated. The photochemical and electrochemical properties for Sr-NDI@AQ were characterized through a series of experiments. The coupling reaction between aldehyde and phenyl vinyl sulfone and photoacetalization reaction were carried out, displaying the improving catalytic efficiency of Sr-NDI@AQ compared to Sr-NDI and AQ. The reaction mechanisms were proposed through radical capture and electron paramagnetic resonance experiments.

Carbonaceous materials featuring both ordered graphitic structure and disordered defects hold great promise for high-performance K-ion batteries (KIBs) due to the concurrent advantages of high electronic conductivity, fast and reversible K + intercalation/deintercalation, and abundant active K + storage sites. However, it has been a lingering problem and remains a big challenge because graphitization and defects are intrinsic trade-off properties of carbonaceous materials. Herein, for the first time, we propose a cobalt-catalyzed carbonization strategy to fabricate porous carbon nanofibers that incorporate disordered defects in graphitic domain layers (PCNFs-DG) for fast and durable K + storage. The Co catalyst not only ensures the formation of highly graphitized carbon shells around the Co particles but also introduces nanopores and doping defects in the following catalyst removal process. This idea of architecting defected-ordered graphitic carbon engineering guarantees fast reaction kinetics as well as structural stability with negligible interlayer expansion/contraction owing to the uncompromised electronic conductivity, expanded interlayer spacing, and regulated K + storage mechanism. These appealing features translate to a high reversible capacity of 318.5 mAh g -1 at 100 mA g -1 and ultrahigh stability with almost 100% capacity retention over 2000 cycles in KIBs. This work puts in perspective that defected and ordered carbonaceous materials could be simultaneously achieved, advancing their performance for next-generation energy storage systems.

Lithium-ion batteries (LIBs) with liquid electrolytes (LEs) have problems such as electrolyte leakage, low safety profiles, and low energy density, which limit their further development. However, LIBs with solid electrolytes are safer with better energy and high-temperature performance. Thus, solid electrolyte system batteries have attracted widespread attention. However, due to the inherent rigidity of the LATP solid electrolyte, there is a high interface impedance at the LATP/electrode. In addition, the Ti element in LATP easily reacts with the Li metal. Here, we dripped an LE at the LATP/electrode interface (solid-liquid hybrid electrolytes) to reduce its interface impedance. A composite polymer electrolyte (CPE) protective film (containing PVDF, SN, and LiTFSI) was then cured in situ at the LATP/Li interface to avoid side reactions of LATP. The discharge specific capacity of the LiFePO 4 /LATP-12% LE-CPE/Li system is up to 150 mAh g -1 , and the capacity retention rate is still 96% after 250 cycles. In addition, the NCM622/PVDF-LATP-12% LE/Li system has an initial reversible capacity of 170 mAh g -1 . This study reports an approach that can protect solid electrolytes from lithium metal instability.

One critical problem inhibiting the application of MoS 2 field-effect transistors (FETs) is the hysteresis in their transfer characteristics, which is typically associated with charge trapping (CT) and charge detrapping (CDT) induced by atomic defects at the MoS 2 -dielectric interface. Here, we propose a novel atomistic framework to simulate electronic processes across the MoS 2 -SiO 2 interface, demonstrating the distinct CT/CDT behavior of different types of atomic defects and further revealing the defect type(s) that most likely cause hysteresis. An anharmonic approximation of the classical Marcus theory is developed and combined with state-of-the-art density functional theory to calculate the gate bias-dependent CT/CDT rates. All the key electronic quantities are calculated with Heyd-Scuseria-Ernzerhof hybrid functionals. The results show that single Si-dangling bond defects are active electron trapping centers. Single O-dangling bond defects are active hole trapping centers, which are more likely to be responsible for the hysteresis phenomenon due to their significant CT rate and apparent threshold voltage shift. In contrast, double Si-dangling bond defects are not active trap centers. These findings provide fundamental physical insights for understanding the hysteresis behavior of MoS 2 FETs and provide vital support for understanding and solving the reliability of nanoscale devices.

Because of the blood-brain barrier and the high infiltration of glioma cells, the diagnostic accuracy and treatment efficiency of gliomas are still facing challenges. There is an urgent need to explore the integration of diagnostic and therapeutic methods to achieve an accurate diagnosis, guide surgery, and inhibit postoperative recurrence. In this work, we developed a macrophage loaded with a photothermal nanoprobe (MFe 3 O 4 -Cy5.5), which is able to cross the blood-brain barrier and accumulate into deep gliomas to achieve multimodal imaging and guided glioma surgery purposes. With desirable probing depth and high signal-to-noise ratio, Fe 3 O 4 -Cy5.5 can perform fluorescence, photoacoustic, and magnetic resonance imaging, which can distinguish brain tumors from the surrounding normal tissues and accurately guide glioma resection. Meanwhile, Fe 3 O 4 -Cy5.5 can effectively induce local photothermal therapy and inhibit the recurrence of glioma after surgery. These results demonstrate that the macrophage-mediated Fe 3 O 4 -Cy5.5, which can achieve a multimodal diagnosis, accurate imaging-guided surgery, and effective photothermal therapy, is a promising nanoplatform for gliomas.

With the recent success of immune checkpoint blockade (ICB) in cancer immunotherapy, there has been renewed interest in evaluating the combination of ICB inhibitors with radiotherapy (RT) in clinical trials in view of the localized RT-initiated vaccination effect, which can be augmented further by systemic immune-stimulating agents. Unfortunately, traditional RT/ICB accompanies severe toxicity from high-dose ionizing irradiation and low response rate from RT-aggravated immunosuppression, among which M2-type tumor-associated macrophages (TAMs) play an important role. Herein, CpG-decorated gold (Au) nanoparticles (CpG@Au NPs) were fabricated to improve the RT/ICB efficacy by immune modulation under low-dose X-ray exposure, where Au NPs served as radioenhancers to minimize the radiotoxicity, and yet acted as nanocarriers to deliver CpG, a toll-like receptor 9 agonist, to re-educate immunosuppressive M2 TAMs to immunostimulatory M1 counterparts, thus arousing innate immunity and meanwhile priming T cell activation. When combined with an anti-programmed death 1 antibody, irradiated CpG@Au led to consistent abscopal responses that efficiently suppressed distant tumors in a bilateral GL261 tumor-bearing model. This work thus demonstrates that CpG@Au-mediated macrophage reeducation could efficiently modulate the tumor-immune microenvironment for synergistic RT/ICB.

Bioinspired artificial nanochannels for molecular and ionic transport have extensive applications. However, it is still a huge challenge to achieve an intelligent transport system with high selectivity/efficiency and controllability. Inspired by glutathione transport across the plasma membrane via redox regulation, we herein designed and fabricated a redox-reactive artificial nanochannel based on the host-guest chemical strategy. The nanochannel platform achieved high selectivity/efficiency for the identification and transmission of glutathione in the confined space. In addition, this nanochannel can switch between the ON and OFF states through the redox reaction. This redox-regulated system can provide a potential application for detection/binding of biological analytes and redox-controlled drug release.

Light-driven polymerization, such as photoinduced electron/energy transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization, enables biological benign conditions and versatile functional polymer structure design, which is readily used in protein-polymer bioconjugates. However, conventional metalloporphyrinic homogeneous catalysts for PET-RAFT polymerization suffer from limited aqueous solubility and tedious purification. Here we demonstrate the design of PET-RAFT photocatalyst from the reticular assembled Zr-porphyrinic metal-organic frameworks (MOFs), along with a biomacromolecule-based chain transfer agent, as efficient bioconjugation tools in water. Our methodology offers manufacturing advantages on bioconjugates under mild conditions such that MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) and cytotoxicity assays have shown the preservation of the protein integrity, bioactivity, and high cell viability after PET-RAFT polymerization. We find that the fast kinetics are benefiting from the ultrahigh loading of metalloporphyrins in MOF-525-Zn. This heterogeneous catalyst also allows us to maintain living characteristics to incorporate myriads of monomers into block copolymers. Other advantages like easy postreaction purification, reusability, and high oxygen tolerance even in an open system are demonstrated. This study provides a tool of highly efficient heterogeneous photocatalysts for polymer-protein bioconjugation in aqueous media and paves the road for biological applications.

Amorphous nanostructures usually exhibit special and intriguing catalytic activities, and the electrochemical performance can be tuned during operation. Herein, a facile approach of the self-activation of amorphous platinum (A-Pt) nanospheres has been applied to develop a durable and efficient hydrogen electrode catalyst toward both the hydrogen evolution reaction (HER) and the hydrogen oxidation reaction (HOR), which was in situ converted to crystalline counterparts and partially oxidized during the electrochemical cycling, leading to the self-activated enhancements of both HER and HOR activities with the decreased overpotential by 5 times and the increased hydrogen oxidation current density by 67%, respectively. Especially, in addition to 12 times higher mass activity compared to benchmark Pt/C, in situ -activated A-Pt also demonstrated a lower HER overpotential even after 20 000 cycles than Pt/C. The significantly improved catalytic performance benefits from the rapid self-reconstruction processes (crystallization and oxidation) of the amorphous Pt during electrochemical cycling. This work shows the intriguing properties of the amorphous nanostructure and provides a new idea for designing an efficient electrocatalyst by phase engineering.

Exploiting novel nanomaterials with fast and durable sodium/potassium ion storage capability is key to alleviate the application limitations of lithium-ion batteries. Herein, a novel energy storage material based on cobalt metaphosphate nanosheet arrays self-supported on carbon cloths [Co(PO 3 ) 2 NSs/CC] is fabricated by a two-step strategy. This rationally designed strategy avoids the preparation of the complex {Co[O 2 P(O t Bu) 2 ] 2 } n precursor, which significantly simplifies the synthesis process. The active CC acts not only as an electrically conductive substrate as usual but also as a functional basis to suppress PH 3 -involved reaction and to promote HPO 3 -involved reaction during the phosphating process, contributing to the formation of Co(PO 3 ) 2 . The mutual cross-linked porous Co(PO 3 ) 2 nanosheets vertically grow on the surface of activated CC, ensuring sufficient electrolyte infiltration and fast electron transport among the electrodes. Sodium ion storage analysis for the Co(PO 3 ) 2 NSs/CC electrode reveals a multi-step reaction mechanism with high reversibility, as reflected by the high reversible capacity (667 mA h g -1 at 50 mA g -1 ) and excellent cyclability (with almost no capacity decay over 500 cycles). This novel electrode is also well capable of storing potassium ions, exhibiting high reversible capacity, which outperforms most reported anodes for potassium-ion batteries. The development of this novel high-performance nanomaterial would advance the performance of sodium/potassium-ion batteries toward practical applications.

Hydrogen atom transfer (HAT) has become an attractive strategy for the activation of hydrocarbon feedstocks. Alcohols, as inexpensive and efficient hydrogen transfer reagents, have limited application in C-H functionalization due to the difficulty in the alkoxy radical acquisition. 9-Fluorenone moieties were incorporated into the metal-organic framework (MOF) as a photocatalyst; through the formation of hydrogen bonds between the carbonyl group of a ligand and alcohol, alkoxy radicals could be obtained by the visible-light-driven oxidation of 2,2,2-trichloroethanol via proton-coupled electron transfer (PCET). Effectively photocatalyzed intermolecular coupling reactions between phenyl vinyl sulfone and aldehyde or cyclic ether were realized through the HAT pathway. Compared to homogeneous catalysts, the heterogeneous MOF photocatalyst improved the catalytic efficiency and could be recycled at least five times. The microenvironment of the Zn-OFDC channel was beneficial for the formation of hydrogen bonds and stability of alkoxy radicals.

O3-type NaCrO 2 is attracting increasing attention as potential cathode material for sodium-ion batteries (SIBs). Bare NaCrO 2 is usually synthesized by a solid-state reaction and suffers from serious capacity decay and poor power capability. Modification by coating is an effective method to improve the electrochemical properties, but it inevitably reduces the energy density. To avoid the decrease of energy density and optimize the electrochemical performance, a specific route, i.e., a freeze-drying-assisted sol-gel method, has been adopted to synthesize bare NaCrO 2 in this work. Three-phase coexistence during charging is confirmed for the first time, which contributes to delaying the disappearance of the O3 phase and then improving the structural reversibility, resulting in superior cycle stability (∼50% capacity retention after 3000 cycles at 5C). Meanwhile, as-synthesized NaCrO 2 delivers an outstanding rate capability (82.1 mAh g -1 at 50C), which is attributed to the fast Na + diffusivity and high electronic conductivity proved by density functional theory (DFT) calculations. It is worth mentioning that NaCrO 2 also exhibits excellent electrochemical properties when used as a cathode for potassium-ion batteries (PIBs). This work provides new perspectives on the structural evolution of NaCrO 2 , and the results are expected to contribute to the development of SIBs and PIBs.

Metal oxide semiconductors, such as amorphous indium gallium zinc oxide (a-IGZO), have made impressive strides as alternatives to amorphous silicon for electronics applications. However, to achieve the full potential of these semiconductors, compatible unconventional gate dielectric materials must also be developed. To this end, solution-processable self-assembled nanodielectrics (SANDs) composed of structurally well-defined and durable nanoscopic alternating organic (e.g., stilbazolium) and inorganic oxide (e.g., ZrO x and HfO x ) layers offer impressive capacitances and low processing temperatures ( T ≤ 200 °C). While SANDs have been paired with diverse semiconductors and have yielded excellent device metrics, they have never been implemented in the most technologically relevant top-gate thin-film transistor (TFT) architecture. Here, we combine solution-processed a-IGZO with solution-processed four-layer Hf-SAND to fabricate top-gate TFTs, which exhibit impressive electron mobilities (μ SAT = 19.4 cm 2 V -1 s -1 ) and low threshold voltages ( V th = 0.83 V), subthreshold slopes (SS = 293 mV/dec), and gate leakage currents (10 -10 A) as well as high bias stress stability.

In order to achieve safe and high-efficient photodynamic therapy (PDT), it was a powerful strategy of constructing O 2 -generated nanozyme with intelligent "off/on" modulation and enhancement. Herein, a kind of H 2 O 2 -responsive nanozyme was developed for off/on modulation and enhancement of magnetic resonance (MR) imaging and PDT, in which great amounts of gold nanoclusters (AuNCs) were loaded into mesoporous silica to form nanoassembly, and manganese dioxide (MnO 2 ) nanosheets were wrapped as switching shield shell (AuNCs@mSiO 2 @MnO 2 ). In a neutral physiological environment, stable MnO 2 shells eliminated singlet oxygen ( 1 O 2 ) generation to switch off PDT and MR imaging. However, in an acidic tumor microenvironment, the MnO 2 shell reacted with H 2 O 2 , in which MnO 2 degradation switched on MR imaging and PDT, and the generated O 2 further enhanced PDT. H 2 O 2 -responsive MnO 2 degradation brought about excellent MR imaging with a longitudinal relaxation rate of 25.31 mM -1 s -1 , and simultaneously sufficient O 2 generation guaranteed a 74% high 1 O 2 yield. Under the irradiation of a 635 nm laser, the viability of MDA-MB-435 cells was reduced to 4%, and the tumors completely disappeared, demonstrating strong PDT performance. Therefore, H 2 O 2 -responsive AuNCs@mSiO 2 @MnO 2 nanozyme showed excellent off/on modulation and enhancement of MR imaging and PDT and was a promising intelligent nanoprobe for safe and high-efficiency theranostics.

Low-temperature, solution-processable, high-capacitance, and low-leakage gate dielectrics are of great interest for unconventional electronics. Here, we report a near room temperature ultraviolet densification (UVD) methodology for realizing high-performance organic-inorganic zirconia self-assembled nanodielectrics (UVD-ZrSANDs). These UVD-ZrSAND multilayers are grown from solution in ambient, densified by UV radiation, and characterized by X-ray reflectivity, atomic force microscopy, X-ray photoelectron spectroscopy, and capacitance measurements. The resulting UVD-ZrSAND films exhibit large capacitances of >700 nF/cm 2 and low leakage current densities of <10 -7 A/cm 2 , which rival or exceed those synthesized by traditional thermal methods. Both the p-type organic semiconductor pentacene and the n-type metal oxide semiconductor In 2 O 3 were used to investigate UVD-ZrSANDs as the gate dielectric in thin-film transistors, affording mobilities of 0.58 and 26.21 cm 2 /(V s), respectively, at a low gate voltage of 2 V. These results represent a significant advance in fabricating ultra-thin high-performance dielectrics near room temperature and should facilitate their integration into diverse electronic technologies.

Photodynamic therapy (PDT) and photothermal therapies (PTTs) are both promising strategies for effective tumor therapy. However, the absence of O 2 at tumor sites hinders the sustained response of photosensitizers. Here, we develop a recycled cerium oxide (CeO 2 ) catalase nanozyme-loaded hyaluronic acid nanovesicle to address the hypoxic tumor microenvironments and targeted delivery of the photosensitizers [indocyanine green (ICG)] to tumors. A polysaccharide complex effectively modifies the surface of a polyethylenimine phenylboronic acid nanostructure to achieve the CeO 2 nanozyme-loading nanovesicles that exhibit both tumor-targeted enhancement and an improved hypoxic microenvironment. Also, the hydrogen peroxide responsiveness and acid-sensitive cleavage of phenylboronic acid specifically disintegrate the ICG/nanozyme coloaded nanovesicles in the tumor microenvironment. The in vitro synergistic tests and tumor suppression rate tests indicated that the cerium oxide nanozyme significantly improves the outcomes of PDT via cerium-element valence state recycling and hypoxia improvement, thus enhancing the tumor suppression efficiency. This pH/H 2 O 2 -responsive nanozyme/ICG codelivery system provides a good carrier model for improving the tumor microenvironment and increasing the efficiency of tumor-targeted PTT and PDT therapies.

Immunochromatographic assay (ICA) is widely applied in various fields. However, severe matrix interference and weak signal output present major challenges in achieving accurate and ultrasensitive detection in ICA. Here, a polydopamine (PDA)-mediated magnetic bimetallic nanozyme (Fe 3 O 4 @PDA@Pd/Pt) with peroxidase-like activity was synthesized and used as a probe in ICA. The magnetic property of Fe 3 O 4 @PDA@Pd/Pt enabled effective magnetic enrichment of targets, thereby reducing the matrix interference in the sample. PDA coating on the magnetic bimetallic nanozyme was employed as a mediator and a stabilizer. It improved the catalytic ability and stability of the magnetic bimetallic nanozyme by providing more coordination sites for Pd/Pt growth and functional groups (-NH and -OH). In addition, the Pd/Pt bimetallic synergistic effect could further enhance the catalytic ability of the nanozyme. A method was developed by integrating Fe 3 O 4 , PDA, and Pd/Pt into Fe 3 O 4 @PDA@Pd/Pt as a probe in ICA. With the proposed method, human chorionic gonadotropin and Escherichia coli O157:H7 were successfully detected to be as low as 0.0094 mIU/mL in human blood serum and 9 × 10 1 CFU/mL in the milk sample, respectively. This method may be readily adapted for accurate and ultrasensitive detection of other biomolecules in various fields.

Formamidinium lead triiodide (FAPbI 3 ) exhibits the smallest band gap among lead halide perovskites, which is more desirable for solar cell applications compared to methylammonium-based counterparts. However, it remains a big challenge to prepare phase-pure α-FAPbI 3 in addition to controlling the crystal morphology during film formation. Herein, we developed a temperature-assisted crystal growth to prepare high-quality thin films of α-FAPbI 3 by sequential blade coating. It is found that depositing organic cation FAI at elevated temperatures facilitates the growth of α-FAPbI 3 , which otherwise yields mainly a yellow δ-phase at room temperature. In parallel, the crystal morphology of the perovskite films can be effectively manipulated by taking advantage of the porous structure of PbI 2 . Solar cells prepared with the blade-coated α-FAPbI 3 yield a champion efficiency of 18.41%, which is among the highest values for FAPbI 3 -only solar devices. These results suggest that two-step sequential blade deposition offers a viable approach to fabricate high-quality α-FAPbI 3 films for optoelectronic applications.

Photodynamic therapy is a medical technique, which is gaining increasing attention to treat various types of cancer. Among the investigated classes of photosensitizers (PSs), the use of Ru(II) polypyridine complexes is gaining momentum. However, the currently investigated compounds generally show poor cancer cell selectivity. As a consequence, high drug doses are needed, which can cause side effects. To overcome this limitation, there is a need for the development of a suitable drug delivery system to increase the amount of PS delivered to the tumor. Herein, we report the encapsulation of a promising Ru(II) polypyridyl complex into polymeric nanoparticles with terminal biotin groups. Thanks to this design, the particles showed much higher selectivity for cancer cells in comparison to noncancerous cells in a 2D monolayer and 3D multicellular tumor spheroid model. As a highlight, upon intravenous injection of an identical amount of the Ru(II) polypyridine complex of the nanoparticle formulation, an improved accumulation inside an adenocarcinomic human alveolar basal epithelial tumor of a mouse up to a factor of 8.7 compared to the Ru complex itself was determined. The nanoparticles were found to have a high phototoxic effect upon one-photon (500 nm) or two-photon (800 nm) excitation with eradication of adenocarcinomic human alveolar basal epithelial tumor inside a mouse model. Overall, this work describes, to the best of our knowledge, the first in vivo study demonstrating the cancer cell selectivity of a very promising Ru(II)-based PDT photosensitizer encapsulated into polymeric nanoparticles with terminal biotin groups.

Ge-based materials have garnered much attention in lithium-ion batteries (LIBs) for their high theoretical capacity, but these materials suffer from huge volume changes and serious pulverization, which cause insufficient lithium storage performance. Herein, a composite composed of Co 5 Ge 3 - and nitrogen-doped carbon nanotube (Co 5 Ge 3 /N-CNT) was successfully synthesized using ZIF-67 and GeO 2 as precursors. There are interactions between the Co 5 Ge 3 alloy nanoparticles and carbon nanotubes in the growth process, in which the Co 5 Ge 3 alloy nanoparticles were confined in situ in N-CNTs and the in situ growth of N-CNTs was boosted in the existence of the Co 5 Ge 3 catalyst. Density functional theory calculations revealed that the electronic conductivity of the Co 5 Ge 3 alloy is much higher than that of Ge and the Li + interaction energy of the former is lower than that of the latter. In addition, the interconnected carbon nanotubes not only offer Li + diffusion pathways and electronic networks but also increase electronic conductivity. Importantly, carbon nanotubes and Co metal have a synergistic effect of buffering volume charge of Ge in the process of Li + intercalation/deintercalation. As expected, the Co 5 Ge 3 /N-CNT composite demonstrated a high reversible capacity of 853.7 mA h g -1 at 2 A g -1 after 1500 cycles and attractive rate performance of up to 10 A g -1 .

Fabrication of superior nonprecious electrocatalysts is essential for water electrolysis. Herein, the epitaxial growth of the XMoO 4 (X = Ni, Co, Fe) nanosheets on the hexagonal MoO 2 nanoplates are carried out. The preoxidation of MoO 2 nanoplate is fatal to the epitaxial growth of a nanosheets array on MoO 2 nanoplates. The hierarchical heterostructure of the vertically aligned NiMo nanosheets on MoO 2 nanoplate (NiMo/MoO 2 ) is well-maintained in the process of in situ topotactic reduction transformation from NiMoO 4 · x H 2 O/MoO 2 . Attributing it to the rich electroactive sites from nanosheets array, together with the intrinsic electrocatalytic performance of NiMo alloy, the as-engineered NiMo/MoO 2 as electrocatalyst exhibits admirable hydrogen evolution reaction (HER) activity with a small onset potential of -12 mV vs RHE (1 mA cm -2 ) and a tafel value of 43.6 mV dec -1 at alkaline media. Furthermore, the obtained CoMoO 4 /MoO 2 possesses excellent oxygen evolution performance, which is verified by an ultralow overpotential of 230 mV@10 mA cm -2 , small Tafel slope (51 mV dec -1 ), and robust durability. The developed NiMo/MoO 2 and CoMoO 4 /MoO 2 electrocatalysts are assembled into an alkaline electrolyzer, which affords a cell potential of 1.51 V at 10 mA cm -2 , as well as outstanding operational durability, which is superior to the typically constructed 20 wt % Pt/C-RuO 2 system (1.59 V at 10 mA cm -2 ). Hence, the universal strategy using MoO 2 nanoplates as Mo source and epitaxial substrate may be extended to explore and construct economical and superior Mo-based electrocatalysts for water electrolysis.

Multifunctional hydrogels have important applications in various fields such as artificial muscles, wearable devices, soft robotics, and tissue engineering, especially for those with favorable mechanical properties, good low-temperature resistance, and stimuli-responsive capabilities. In the current study, a type of polyacrylamide/sodium alginate/carbon nanotube (PAAm/SA/CNT) double-network (DN) hydrogel was fabricated, which exhibited a high tensile strength of 271.68 ± 6.04 kPa, a favorable conductivity of 1.38 ± 0.17 S·m -1 , and a good self-healing ability under heating conditions. In addition, the composite hydrogel exhibited controllable photomechanical deformations under near-infrared irradiation, such as bending, swelling, swimming, and object grasping. To further broaden the applications of the hydrogel in low-temperature environments, calcium chloride (CaCl 2 ) was introduced into such a PAAm/SA/CNT DN hydrogel as an additive. Interestingly, the tensile/compressive strengths as well as elasticity were well-maintained at a temperature as low as -20 °C. In addition, the PAAm/SA/CNT/CaCl 2 hydrogel presented excellent conductivity, recoverability, and strain-sensing capability under such extreme conditions. Overall, the investigations conducted in this paper have provided potentially new methods and inspirations for the generation of multifunctional PAAm/SA/CNT/CaCl 2 hybrid DN hydrogels toward extended applications.

We report the preparation of porous hydrous zirconia by treatment of zirconium-based metal-organic framework (MOF) UiO-66 with a strong base. Microporosity of the original MOF was partially retained in the resultant porous hydrous zirconia. Ni II centers were then adsorbed onto the OH-rich hydrous zirconia and in situ converted to highly dispersed Ni 0 for CO 2 hydrogenation to CH 4 . The activated catalyst after an induction period showed a turnover frequency of 345 h -1 or a space-time yield of 5851 mmol·g Ni -1 ·h -1 with a CH 4 selectivity of over 99%. The catalyst was tested for 100 h on stream, showing only a 4% decrease in activity, and was found to convert atmospheric CO 2 to CH 4 via CO 2 collection through Na 2 CO 3 /NaHCO 3 cycling. Thermal decomposition of NaHCO 3 released CO 2 for hydrogenation to CH 4 , and the resultant Na 2 CO 3 absorbed CO 2 from air to form NaHCO 3 . This work highlights the opportunity in using MOFs as precursors to prepare highly porous metal oxide/hydroxide supports for solid-gas phase catalysis.

Light-responsive nanoprobes were suffering from the threat of high-dose laser irradiation, and it was important for constructing new nanoprobes for safe and efficient phototheranostics. Here, polydopamine (PDA)-coated gold nanobipyramids (AuNBPs@PDA) were synthesized for amplified photoacoustic (PA) signal and enhanced photothermal conversion with low-dose laser irradiation and then doxorubicin (DOX)-loaded AuNBPs@PDA-DOX nanoprobes were constructed for PA imaging-guided synergistic photothermal therapy (PTT) and chemotherapy. The AuNBPs@PDA nanoparticles possessed higher photothermal conversion efficiency (42.07%) and stronger PA signal than those of AuNBP nanoparticles, and the AuNBPs@PDA-DOX nanoprobes showed dual-responsive DOX release of pH and photothermal stimulation. With low-dose laser irradiation (1.0 W/cm 2 ) and low-concentration AuNBPs@PDA-DOX (60 μg/mL), the 4T1 cell viability was reduced to about 5%, owing to the combination of PTT and chemotherapy, compared with 42.3% of single chemotherapy and 25.3% of single PTT. Moreover, by modeling 4T1 tumor-bearing nude mice, in vivo PA imaging was achieved and the tumors were completely inhibited, demonstrating the excellent synergistic effect of PTT/chemotherapy. Therefore, the developed AuNBPs@PDA-DOX nanoprobes can be used for phototheranostics and synergistic chemotherapy, achieving low-dose laser irradiation and high-efficient visualized theranostics.

Recently, potassium-ion batteries (PIBs) are being actively investigated. The development of PIBs calls for cathode materials with a rigid framework, reversible electrochemical reactivity, and a high amount of extractable K ions, which is extremely challenging due to the large size of potassium. Herein, a new layered compound K 0.83 V 2 O 5 is reported as a potential cathode material for PIBs. It delivers an initial depotassiation capacity of 86 mAh g -1 and exhibits a reversible capacity of 90 mAh g -1 with a high redox potential of 3.5 V (vs K + /K) and a capacity retention of more than 80% after 200 cycles. Experimental investigations combined with theoretical calculation indicate that depotassiation-potassiation is accommodated by contraction-expansion of the interlayer spacing along with unpuckering-puckering of the layers. Additionally, the calculated electronic structure suggests the (semi)metallic feature of K x V 2 O 5 (0 < x ≤ 0.875) and K-ion transport in the material is predicted to be one-dimensional with the experimentally estimated chemical diffusion coefficient in the order of 10 -15 -10 -12 cm 2 s -1 . Finally, a K-ion full cell consisting of the K 0.83 V 2 O 5 cathode and a graphite anode is demonstrated to deliver an energy density of 136 Wh kg -1 . This study will provide insights for further designing novel layered cathodes with high K-ion content for PIBs.

As a green, pollution-free, and renewable clean energy source, photocatalytic H 2 production has attracted great attention. Here, epitaxial growth of pyramidal CdS-Cd nanoparticles on S-doped MoO 2 nanosheets (CdS-Cd/S-MoO 2 ) was prepared by one-step co-sublimation of CdS and MoO 3 . The photogenerated electrons of CdS as a photocatalyst are transferred to Cd and S-MoO 2 as co-catalysts for H 2 production, which is observed by surface photovoltage (SPV) under visible light irradiation. At last, the obtained CdS-Cd/S-MoO 2 presented an efficient photocatalytic performance under the visible light (>420 nm) with a prominent H 2 generation rate of as high as 24.98 μmol h -1 mg -1 , which is 11 times higher than that of the CdS-Cd nanoparticles (2.26 μmol h -1 mg -1 ), and it is superior than that of the CdS (1.51 μmol h -1 mg -1 ).

Design and fabrication of flexible Li-ion batteries (FLIBs) with excellent electrochemical and structural stability via scalable fabrication techniques are important for their practical applications. A wide range of FLIBs with excellent flexibility have been reported. However, sophisticated designs and complex fabrication techniques are often used in fabricating FLIBS, making them difficult to be realized in industrial production. Here, we fabricate FLIBs with an integrated structure by assembling the LiFePO 4 cathode, Li 4 Ti 5 O 12 anode, graphene current collectors, and poly(vinylidene fluoride) (PVDF) electrolyte all together on commercial printing paper via conventional and scalable Meyer rod coating. In the design, the commercial paper serves as a flexible substrate to enable good flexibility of the device, and the paper is coated twice with PVDF to avoid the short-circuit problem and create a strong binding to integrate the device. The resultant integrated FLIBs exhibit excellent internal structural stability and good electrochemical performance under cycling bending for 100 times.

Traditional tumor treatments suffer from severe side effects on account of their invasive process and inefficient outcomes. Featuring a unique physical microenvironment, the tumor microenvironment (TME) provides a new research direction for designing more efficient and safer treatment paradigms. In this study, we fabricated a polydopamine (PDA)-based TME-responsive nanosystem, which successfully integrates glucose degradation, the Fenton reaction, and photothermal therapy for efficient cancer therapy. Through a convenient hydrothermal method, Fe 2+ -doped Fe(II)-PDA nanoparticles were successfully fabricated, which show an excellent photothermal effect and interesting reactivity for the Fenton reaction. Instead of introducing toxic anticancer agents, natural glucose oxidase (GOD) was grafted on Fe(II)-PDA, forming a cascade catalytic nanomedicine for a specific response to the glucose in TME. GOD grafted on Fe(II)-PDA-GOD is ought to catalyze abundant glucose in TME into gluconic acid and H 2 O 2 . The concomitant generation of H 2 O 2 can enhance the efficiency of the sequential Fenton reaction, producing abundant hydroxyl radicals ( • OH) for cancer therapy. Besides, the overconsumption of intratumoral glucose also could inhibit tumor growth by reducing the energy supply. Taken together, the in vitro and in vivo antitumor studies of such TME-based Fe(II)-PDA-GOD nanosystems displayed a favorable synergistic potency of glucose degradation, the Fenton reaction, and photothermal therapy against tumor growth. Our design expands the biological application of multifunctional PDA while providing novel strategies toward effective antitumor treatment with minimal side effects.

A charge-reversal amphiphilic pillar[5]arene, P5NH-DCA, bearing 10 charge-reversal headgroups is reported. It targets the cell membrane of cancer cells and selectively destroys the cancer cells by disrupting the membrane. In the acidic tumor microenvironment, the headgroup charge of P5NH-DCA reversed from negative to positive owing to hydrolysis of the acid-labile amide group. The hydrolyzed product bearing multiple positive charges can bind to the cell membrane and then disrupt the membrane of cancer cells with high efficiency. However, under the neutral microenvironment of healthy cells, the negatively charged P5NH-DCA remains stable and the cytotoxicity is considerably reduced. The strategy killing the cancer cells by membrane disruption may represent a new route of cancer chemotherapy.