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Copper phenylacetylide (PACu) is a promising photocatalyst due to its unique copper ladder (CL) electron transport channel, which facilitates efficient charge transfer. However, the structure-activity relationship between the CL spacing and its catalytic performance has yet to be revealed. In this study, we skillfully selected multiple substituents to regulate the CL spacing of the PACu photocatalyst. Our findings indicate that reducing the CL spacing significantly enhances carrier separation and transport efficiency, leading to improved oxygen adsorption and activation. Specifically, PACu-F demonstrated superior photocatalytic activity, achieving a 99% conversion rate in benzylamine oxidation and maintaining an excellent stability over multiple cycles. This study confirms the feasibility of tuning the CL spacing in PACu using donor/acceptor substituents to achieve a high-efficiency photocatalytic performance, offering crucial insights into the rational design of advanced photocatalysts.

Superhydrophobic surfaces exhibit considerable potential in road anti-icing applications due to their unique water-repellent properties. However, the nanorough structure of superhydrophobic coatings is highly susceptible to degradation under wheel rolling in practical applications. To maintain effective hydrophobicity under prolonged exposure to wheel rolling, a multilayer superhydrophobic anti-icing coating was developed. This coating utilizes antifreeze protein (AFP)-modified emulsified asphalt as the substrate with carbon nanotubes (CNTs) and silicon carbide (SiC) as surface coatings. Experimental results indicate that the inclusion of AFP enhances the viscosity of the emulsified asphalt, thereby stabilizing the nanorough structure of the coating. Even after 100 cycles of sandpaper grinding and 500 wheel rolls, the coating maintains robust hydrophobic properties. Moreover, when the coating is worn away by long-term high-strength loads, the exposed AFP-modified emulsified asphalt layer continues to exhibit effective anti-icing capabilities, significantly prolonging the complete freezing time of water droplets on its surface. Additionally, the incorporation of CNTs and SiC enhances the photothermal conversion performance, further improving the anti-icing efficiency of the coating under light irradiation. Overall, this coating shows promise for application in road anti-icing strategies.

Hierarchically structural particles (HSPs) are highly regarded as favorable nanomaterials for superhydrophobic coating due to their special multiscale structure and surface physicochemical properties. However, most of the superhydrophobic coatings constructed from HSPs are monofunctional, constraining their broader applications. Moreover, traditional methods for constructing HSPs mostly rely on complicated chemical routes and template removal. Herein, we propose an innovative strategy (one-pot method) for producing multifunctional hierarchical hybrid particles (HHPs). Polysilsesquioxane (PSQ), generated from hydrolysis condensation of methyltriethoxylsilane, is used as the sole stabilizer to anchor on the surface of styrene and short fluoroalkyl compound tridecafluorooctyl acrylate comonomers droplets, forming a mesoporous PSQ shell. Subsequently, the comonomers inside of the shell perform restricted polymerization to generate the HHP due to the driving of the mesoporous capillary force. The HHP is then mixed with waterborne polyurethane (WPU) to develop a robust nanocomposite coating (WPU-HHP). Through the deliberate design of the HHP components, the WPU-HHP coating has thermal insulation, photoluminescence properties, and the ability to achieve a wettability transition during abrasion. Our research has achieved the integration of multifunctionality in one waterborne hybrid system, broadening the application areas of nanocomposite coatings.

Poly(ethylene oxide) (PEO)-based electrolytes have been extensively studied for all-solid-state lithium-metal batteries due to their excellent film-forming capabilities and low cost. However, the limited ionic conductivity and poor mechanical strength of the PEO-based electrolytes cannot prevent the growth of undesirable lithium dendrites, leading to the failure of batteries. Metal-organic frameworks (MOFs) are functional materials with a periodic porous structure that can improve the electrochemical performance of PEO-based electrolytes. However, the enhancement effect of MOFs with different metal centers and the interaction mechanism with PEO remain unclear. Herein, MOF-74s with Cu or Ni centers are prepared and used as fillers of PEO-based electrolytes. Adding 15 wt % of Cu-MOF-74 to the PEO-based electrolyte (15%Cu-MOF/P-Li) effectively improves the ionic conductivity, lithium transference number, and mechanical strength of the PEO-based electrolyte simultaneously. Furthermore, the ordered pore channels of Cu-MOF-74 provide uniform Li-ion transport pathways, facilitating homogeneous Li + deposition. As a result, the lithium symmetric cell with 15%Cu-MOF/P-Li shows stable cycles for 1080 h at 0.1 mA cm -2 and 0.1 mAh cm -2 , and the Li | 15% Cu-MOF/P-Li | LFP full cell exhibits a long cycle life up to 200 cycles at 60 °C and 0.5 C, with a capacity retention rate of 89.7%.

A surfactant-free soft-templating method has been used to prepare polysiloxane hollow nanoparticles with a controllable shape. This method is simple and has the potential for large-scale preparation. For the first time, we successfully obtained hollow polysiloxane nanoparticles with different shapes, including eccentric hollow polysiloxane microspheres (EHPM), apple-like hollow polysiloxane microparticles (AHPM), and bowl-like hollow polysiloxane microparticles (BHPM), by simply changing the solvent. In this method, the hydrolyzed methyltriethoxysilane (MTES) not only stabilizes the system as a surfactant but also acts as a reactant for subsequent reactions, so no additional surfactant is needed. In addition, the formation mechanism of hollow polysiloxane microparticles with different shapes is also proposed: that is, MTES hydrolyzed under acidic conditions to form a surfactant, which changes the system from suspension to a stable oil-in-water emulsion. Then, under alkaline conditions, the hydrolyzed MTES polycondenses and nucleates at the oil-water interface. At the same time, with the process of polycondensation, the hydrolyzed MTES will migrate to the nucleation site driven by surface tension, thus forming an eccentric core/shell (solvent/polysiloxane) structure. Due to the different forces between hydrolyzed MTES and different solvents, the deviation degree of hollow in microspheres is different, thus forming particles with various morphologies. This synthesis method provides a new idea for the preparation of shapeable anisotropic hollow structures. Finally, we use AHPM to study the application of the drug load. The results show that the prepared hollow polysiloxane particles have a good drug loading capacity and release performance. It can be predicted that the shape-tunable hollow polysiloxane particles prepared by this method have broad application prospects in the field of drug delivery.

As a flexible artificial material, the conductive hydrogel has broad application prospects in flexible wearable electronics, soft robotics, and biomedical monitoring. However, traditional hydrogels still face many challenges, such as long-term stability, availability in extreme environments, and long-lasting adhesion to the skin surface under sweaty or humid conditions. To circumvent the above issues, one kind of ionic conductive hydrogel was prepared by a simple one-pot method that dissolved chitosan (CS), 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS), tannic acid (TA), and 2-methoxy-ethyl acrylate (MEA) into dimethyl sulfoxide (DMSO)/H 2 O solvent. The resulting hydrogel showed excellent tensile properties (1440%), extreme environmental tolerance (-40-60 °C), adhesion (72 KPa at porcine skin), ionic conductivity (0.87 S m -1 ), and high-efficiency antibacterial property. Furthermore, the produced organohydrogel strain sensor exhibited high strain sensitivity (GF = 4.07), excellent signal sensing capabilities (human joint movement, microexpression, and sound signals), and long-term cyclic stability (400 cycles). Looking beyond, this work provides a simple and promising strategy for using hydrogel sensors in extreme environments for e-skin, health monitoring, and wearable electronic devices.

Incorporating ITIC derivatives as guest acceptors into binary host systems is an effective strategy for constructing high-performance ternary organic solar cells (TOSCs). In this work, we introduced A-D-A type ITIC derivatives PTBTT-4F (asymmetric) and PTBTP-4F (symmetric) into the PM6:BTP-BO-4F (Y6-BO) binary blend and investigated the impacts of two guest acceptors on the performance of TOSCs. Differentiated device performance was observed, although PTBTT-4F and PTBTP-4F presented similar chemical structures and comparable absorptions. The PTBTT-4F ternary devices exhibited an improved power conversion efficiency ( PCE ) of 17.67% with increased open circuit ( V OC ) and current density ( J SC ), whereas the PTBTP-4F-based ternary devices yielded a relatively lower PCE of 16.34%. PTBTT-4F showed much better compatibility with the host acceptor BTP-BO-4F, so that they formed a well-mixed alloy phase state; more precise phase separation and increased crystallinity were thus induced in the ternary blends, leading to reduced molecular recombination and improved charge mobilities, which contributed to improved fill factors of the ternary devices. In addition, the optimized PTBTT-4F devices exhibited good performance tolerance of the photoactive layer thickness, as they even delivered a PCE of 15.25% when the active layer was as thick as up to ∼300 nm.

The main obstacle to the development of large-scale electrochemical hydrogen production based on water splitting is the slow four-electron kinetics of OER (oxygen evolution reaction). The most efficient method is to create sophisticated and effective OER catalysts. Here, we proposed the controlled synthesis of high-entropy layered double hydroxides (HELDH) for wide component regulation and the component design of high OER activity to make up for the restricted component regulation in conventional catalysts. Through the use of coprecipitation and hydrothermal synthesis, the representative sample (MgCoNi) 3 (FeAl)-LDH is created and systematically characterized. Significantly, this technique of preparation may generically synthesize a variety of HELDH with various component combinations, demonstrating the remarkable adaptability of the HELDH components. Subsequently, (FeCoNi) 3 (FeCr)-LDH with high OER activity is designed and synthesized. (FeCoNi) 3 (FeCr)-LDH shows excellent OER activity (overpotential is only 230 mV at 10 mA cm -2 ). A new platform for the creation of high-performance catalysts and high-entropy materials was established by the synthesis and design of HELDH.

Suitable relative humidity is essential for the preservation of cultural relics, food storage, and so on. A special material that can regulate the relative humidity in the microenvironment is particularly important. In this work, several innovative electrospun films with reversible photoresponsive wettability and the ability to regulate microenvironmental relative humidity were prepared. The spiropyran unit of the synthesized copolymer played the most important role in humidity regulation due to its reversible transition between a nonpolar ring-closed state and a polar ring-opened state induced by alternating ultraviolet/visible illumination. More interestingly, the introduction of acrylic acid segments exhibited a controllable hydrogen bond synergistic effect for increasing the range of humidity regulation. The color change and the reversible change ranges of wettability and microenvironmental relative humidity under ultraviolet/visible irradiation are all closely related to the number of acrylic acid segments. Cassie theory, density functional theory (DFT), and interaction region indicator (IRI) analysis were used to characterize this phenomenon. Electrospinning is a promising method to achieve large-scale production that can put such material into practical applications.

Nickel-based hydroxides and their derivatives exhibit relatively low capacities and unsatisfactory durability as cathode materials for rechargeable alkaline batteries. In this work, a hybrid NiCo-B nanosheet cathode, integrating electrolyte ion-shuttling channels and electron-transferring networks into a metal-organic framework (MOF), was devised delicately. In the structure, the hybrid ion/electron dual pathways were constructed by NiCo-MOF frameworks and NiCo-B interpenetration networks. It revealed that nano-phase electron-transferring pathways in the MOF obviously boosted ion intercalation kinetics. The as-obtained hybrid NiCo-B nanosheets as cathode materials exhibited reversible capacity as high as 280 mA h g -1 at a current density of 1 A g -1 and excellent rate capability with a capacity retention of 78% from 1 to 10 A g -1 . After 2000 charge/discharge cycles at 4 A g -1 , the capacity still remained at 94% of the initial one. A full battery assembled with a hybrid NiCo-B cathode and a Fe 2 O 3 anode showed a high capacity of 250 mA h g -1 and a considerable stability of 89% after 1000 cycles. Ragone plots indicated the highest energy density of 409 W h kg -1 and the lowest power density of 1.5 kW kg -1 , outperforming other aqueous batteries. It revealed that a syngenetic structure of ion/electron hybrid dual pathways integrated into an MOF could be a potential strategy to optimize ion intercalation electrode materials for alkaline batteries.

With the development of flexible surface-enhanced Raman spectroscopy (SERS) substrates that can realize rapid in situ detection, the SERS technique accompanied by miniaturized Raman spectrometers holds great promise for point-of-care testing (POCT). For an in situ detection strategy, constructing high-performance flexible and transparent SERS substrates through a facile and cost-effective fabrication method is critically important. Herein, we present a simple method for fabricating a large-area flexible and transparent SERS substrate consisting of a silver-nanoparticle-grafted wrinkled polydimethylsiloxane (Ag NPs@W-PDMS) film, using a surface-wrinkling technique and magnetron sputtering technology. By characterizing rhodamine 6G as a probe molecule with a portable Raman spectrometer, the flexible SERS substrate shows a low detection limit (10 -7 M), a high enhancement factor (6.11 × 10 6 ), and excellent spot-spot and batch-batch reproducibilities (9.0% and 4.2%, respectively). Moreover, the Ag NPs@W-PDMS substrate maintains high SERS activity under bending and twisting mechanical deformations of over 100 cycles, as well as storage in air for 30 days. To evaluate its practical feasibility, in situ detection of malachite green on apple and tomato peels is performed with a detection limit of 10 -6 M. In addition, for point-of-care analysis, we develop a wireless transmission system to transmit the collected SERS spectral data to a computer in real time for signal processing and analysis. Therefore, the proposed Ag NPs@W-PDMS SERS substrate fabricated through a simple and mass-producible method, combined with the utilization of a portable Raman spectrometer and wireless communication, offers a promising opportunity to extend the SERS technique from the laboratory to POCT applications.

High-performance wearable sensors are required for applications in medical health and human-machine interaction, but their application has limited owing to the trade-off between sensitivity, pressure range, and durability. Herein, we propose the combined spraying and self-diffusion process of carbon nanotubes (CNTs) to balance and improve these parameters with the CNTs spontaneously diffusing into the film surface before the film curing. The obtained sensor not only achieves high sensitivity (155.54 kPa -1 ) and ultrawide pressure detection range (0.1-500 kPa) but also exhibits exceptional durability (over 12,000 pressure cycles at a high pressure of 300 kPa). In addition, the sensor exhibits a fast response (25 ms), good stability, and full flexibility. This process is a general approach that may improve the performance of various types of thin film piezoresistive sensors. Besides, the fabricated sensors can be flexibly scaled into sensor arrays and communicate with smart devices to achieve wireless smart monitoring. At present, the sensor shows broad application prospects in the fields of intelligent medical health and motion sensing.

Single-atom catalysts (SACs) have demonstrated catalytic efficacy toward lithium polysulfide conversion in Li-S batteries. However, achieving high-density M-N x sites with rational design by a simple method is still challenging to date. Herein, an ultrathin porous 3D carbon-supported single-atom catalyst (SACo/NDC) is synthesized with a salt-template strategy via a facile freeze-drying and one-step pyrolysis procedure and serves well as a sulfur host. The well-defined 3D carbon structure can effectively alleviate volume stress and confine polysulfides inside. Moreover, the dispersed Co-N x sites exhibit strong chemical adsorption function and valid catalytic efficiency to LiPSs redox conversion. As a result, the SACo/NDC cathodes display enhanced long-term cycling stability and better rate capability.

Optimizing the water bonding network in an evaporator is significant for efficient solar-driven vapor generation (SVG). Herein, we report a facile one-pot method to regulate the hydrated structure and wettability in a hierarchical porous hydrogel. An ovalbumin (OVA)-polyacrylamide hydrogel foam was fabricated in a cake-making fashion. Because of the enrichment of amphiphilic OVA at the interface, the hydrophobic walls of the air pores in the foam provide vaporization sites and help reduce parasitic heat loss, while the hydrophilic skeleton with the secondary pores effectively pumps capillary water. Notably, the proportion of intermediate water in the foam reaches 87.6% with the melting point as low as -10 °C. All these features contribute to an exceptional evaporation rate of 3.4-4.5 kg m -2 h -1 under 1 sun and robust SVG performances at high-humidity, weak sunlight, or cold weathers. The strategy of using amphiphilic molecules to optimize the hydrated structures both at the interface and in bulk promises the reasonable design of SVG materials with superior efficiency and weather adaptability.

High-energy density and safe solid lithium batteries call for cathodes with high capacity and good kinetic properties. In this work, LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622) cathodes are coated with the ionic-electronic dual-conductive polymers composed of poly(ethylene glycol) (PEG)-doped polyaniline (PANI). Scanning electron microscopy, transmission electron microscopy, Fourier transform infrared, and thermogravimetric analysis reveal that the dual-conductive polymers are homogeneously coated on the surfaces of NCM622 cathodes with a thickness of approximately 10 nm. The solid-state lithium batteries consisting of the NCM622 cathodes coated with PANI-PEG show a specific capacity of 158 mA h g -1 and a retention rate of 88% after 100 cycles at the rate of 0.1 C and room temperature, which are superior to the discharge capacity of 153 mA h g -1 and capacity retention of 59% after 100 cycles for the batteries with the pristine NCM622 cathodes. Moreover, the cells with the coated cathodes display a better rate performance of 84 mA h g -1 at 1 C than those with the uncoated ones which show a rate performance of 11 mA h g -1 at 1 C.

Electrochemical CO 2 reduction can convert waste emissions into dense liquid fuels compatible with existing energy infrastructure. High-rate electrocatalytic conversion of CO 2 to ethanol has been achieved in membrane electrode assembly (MEA) electrolyzers; however, ethanol produced at the cathode is transported, via electroosmotic drag and diffusion, to the anode, where it is diluted and may be oxidized. The ethanol concentrations that result on both the cathodic and anodic sides are too low to justify the energetic and financial cost of downstream separation. Here, we present a porous catalyst adlayer that facilitates the evaporation of ethanol into the cathode gas stream and reduces the water transport, leading to a recoverable stream of concentrated ethanol. The adlayer is comprised of ethylcellulose-bonded carbon nanoparticles and forms a porous, electrically conductive network on the surface of the copper catalyst that slows the transport of water to the gas channel. We achieve the direct production of an ethanol stream of 12.4 wt %, competitive with the concentration of current industrial ethanol production processes.

As a micro-/nano-sized hydrogel, polymeric microgel not only has three-dimensional (3D) molecular networks but also displays the small-size effect, which has been widely used in various fields, such as drug nanocarrier, photonic crystal, functional coating, and aqueous lubrication. In this work, a photothermal lubricating coating was prepared using polymeric/inorganic hybrid microgels and its surficial friction was deliberately modulated by the remote irradiation of near-infrared (NIR) light. Specifically, a photothermal hybrid microgel, Fe 3 O 4 @poly( N -isopropylacrylamide- co -polyacrylic acid) (Fe 3 O 4 @PNA), was first fabricated and then sprayed onto poly(ethyleneimine) (PEI)-modified substrate to form a lubricating microgel coating. At room temperature, this microgel coating was hydrophilic and achieved good hydration lubrication with relatively low friction. After the introduction of NIR light, the photothermal microgel coating converted light energy into heat energy for increasing its own temperature rapidly. Due to the thermosensitive PNA shell, the wettability of the coating was transformed to hydrophobicity above the lower critical solution temperature (LCST), resulting in a remarkable increase in friction. In other words, the surficial friction of this microgel coating could be reversibly modulated using NIR light. This work expands the application scope of microgels in the field of aqueous lubrication and introduces the functional microgels into making the smart lubricating coating for the first time. This basic research in the field of friction control may provide an efficient strategy for the design of interfacial sensing, controlled transmission, and intelligent manipulator.

Photoactuated liquid crystalline elastomer (LCE) materials are gaining much attention in many application fields, but challenges for the precise modulation of their photoresponses still exist. Researchers have explored various optical parameters, such as polarization, intensity, and wavelength, to obtain differential responses. The development of photoactuated LCE materials with wavelength-selective responsiveness is more versatile and has attracted more interest, but such LCE materials are commonly prepared by incorporating different molecular chromophores or dyes into the LCE matrices. When the surface plasmon resonance (SPR) characteristic of nanometals, which can generate strong photothermal conversion, and the difference of SPR absorption wavelength bands of different nanometals are considered, a strategy of constructing wavelength-selective actuation of LCE materials by using the SPR photothermal effect can be demonstrated, as done herein. The LCE nanocomposites doped by nanogold or nanosilver were fabricated and exhibited good SPR absorption but in different wavelength bands of the visible spectrum range. They had strong actuation under light irradiation with the wavelengths being inside their respective absorption band but could not be effectively actuated by the light beyond their respective absorption band. A smart electronic device, implementing a hierarchical structured LCE nanocomposite doped by nanogold and nanosilver in different domains as the two-switch actuator, was prepared and capable of outputting different signals in response to the different wavelength bands filtered from a light source, which released the actuator from the restriction of light scanning direction or position. Our work provides new insights for the convenient and precise photoactuation of the LCE actuators.

All-solid Li-O 2 batteries have been constructed with Ag nanowire (AgNW) cathodes coated on Au-buffered garnet ceramic electrolytes and Li anodes on the other sides. Benefiting from the clean contacts of Li + , e - , and O 2 on the AgNWs, the surface pathway reactions are demonstrated. Upon discharge, two types of Li 2 O 2 morphologies appear. The film-like Li 2 O 2 forms around the smooth surfaces of AgNWs, and hollow disk-like Li 2 O 2 forms at the joints in between the AgNWs as well as at the garnet/AgNW interfaces. The formation of films and hollow disks is in accordance with the process of O 2 + Li + + e - → LiO 2 and 2LiO 2 → Li 2 O 2 + O 2 , indicating that the disproportionation of LiO 2 occurs at the solid interfaces. During the initial charge, decomposition occurs below the potential of 3.5 V, indicating the process of Li 2 O 2 → LiO 2 + Li + + e - and LiO 2 → Li + + e - + O 2 rather than Li 2 O 2 → 2Li + + 2e - + O 2 . The Li 2 O 2 decomposition starts at the AgNWs/Li 2 O 2 interfaces, causing the film-like Li 2 O 2 to shrink and the gas to release, followed by the collapse of hollow disk-like Li 2 O 2 . The results here clearly disclose the Li-O 2 reaction mechanism at the all-solid interfaces, facilitating a deep understanding of key factors influencing the electrochemical performance of the solid-state Li-O 2 batteries.

Three-dimensional (3D) printing is becoming a revolutionary technique across various fields. Especially, digital light processing (DLP) 3D printing shows advantages of high resolution and high efficiency. However, multifunctional monomers are commonly used to meet the rapid liquid-to-solid transformation during DLP printing, and the extensive production of unreprocessable thermosets will lead to resource waste and environmental problems. Here, we report a family of dynamic polymers with highly tailorable mechanical properties for DLP printing. The dynamic polymers cross-linked by ionic bonding and hydrogen bonding endow printed objects with excellent self-healing and recycling ability. The mechanical properties of printed objects can be easily tailored from soft elastomers to rigid plastics to satisfy practical applications. Taking advantage of the dynamic cross-linking, various assembling categories, including 2D to 3D, small to large 3D structures, and same to different materials assembly, and functional devices with a self-healing capacity can be realized. This study not only helps to address environmental issues caused by traditional DLP-printed thermosets but also realizes the on-demand fabrication of complex structures.

Applying extensively excess ammonium halides in forming perovskites is a widely used approach to achieve high-performance perovskite light-emitting diodes (PeLEDs). However, most of these PeLEDs suffer from severe external quantum efficiency (EQE) roll-off at high current densities, thereby restricting the realization of high-brightness PeLEDs and laser diodes. In this work, we explore the underlying mechanism of the EQE roll-off in high-efficiency formamidinium lead iodide (FAPbI 3 )-based PeLEDs. By combining voltage-dependent electrical stress measurements and ex situ ion distribution analysis of PeLEDs, we found that the electric field-driven migration and local segregation of excess iodide ions, originated from nonstoichiometric precursors, trigger the EQE roll-off via promoting imbalanced charge injection. Based on this discovery, we introduced a simple wash-off treatment with chloroform to remove the excess iodides from the perovskite surface and demonstrated that the treatment is highly effective in suppressing the roll-off behavior. By combining the treatment and the use of an ultrathin poly(methyl methacrylate) (PMMA) interlayer, we achieved a high-brightness PeLED with an EQE max of 19.6%, a critical current density of 1550 mA cm -2 , and a radiance max of 875 W sr -1 m -2 . The study reveals the double-edge sword effect of precursor nonstoichiometry and highlights the importance of managing excess ions in perovskite films.

Integration of novel bio-/nanostructures as effective sensing platforms is still of great significance for robust and rapid analysis. Herein, a novel metal-organic framework-derived NiCo 2 O 4 was synthesized via a feasible templating method. Significantly, redox couples of both Ni 3+ /Ni 2+ and Co 3+ /Co 2+ provided richer oxidation-reduction reactions, thereby leading to an enhanced catalytic activity. Furthermore, NiCo 2 O 4 as an enzyme mimic with peroxidase-like activity and oxidase-like activity could oxidize colorless thylbenzidine (TMB) to blue oxTMB in the absence of H 2 O 2 . Thus, a sensitive chromogenic sensing platform for detecting Fe 2+ , thiourea, cysteine (Cys), and epigallocatechin-3-gallate (EGCG) was proposed. The colorimetric detection methods exhibited great features of low limit of detection (LOD) and broad linear range. Owing to the complexation reaction, the chromogenic sensing system of TMB + NiCo 2 O 4 + Cys achieved effective detection of Cu 2+ and Mn 2+ with the LODs of 0.0022 and 0.0181 mM, respectively. Developed detection methods with wide linear ranges of 0.008-0.1 mM for Cu 2+ and 0.08-1 mM for Mn 2+ had excellent practical potential. Similarly, the reaction system of TMB + NiCo 2 O 4 + EGCG could achieve the colorimetric detection of Cu 2+ and Fe 3+ . The great chromogenic sensing performance for detecting Cu 2+ and Fe 3+ with a broad linear range and a low LOD could be also realized.

W atoms/clusters are employed to in situ assist the development of layered vertically aligned carbon nanotube arrays (VACNTs) through hot-filament-assisted chemical vapor deposition (HFCVD) with liquid binary Fe 3 O 4 /AlO x catalysts. The hot W filament was utilized to in situ evaporate atomic W and form W clusters on Fe catalysts, which have a strong impact on the growth of layered VACNT arrays. The migration and Ostwald ripening of Fe catalysts are found to be suppressed immediately with more W clusters deposition during CNT growth. Through controlling the deposition of W clusters, the electrochemical energy storage performance of as-prepared layered VACNT arrays is also tunable as electrodes of ion-based supercapacitors. The layered VACNT arrays can achieve a high capacity of 83.1 mF cm -2 and possess desirable rate performance due to the suitable hot filament condition (55 W for 90 s). This work provides a new perspective to in-depth understand the behavior of W filament during HFCVD and the significant role of the in situ generated W clusters on the growth of CNTs by maintaining the catalytic activity and structure of catalysts.

Transparent superhydrophobic surfaces are of vital significance for rising applications in optoelectronics, outdoor displays, building windows, and so on. However, facile fabrication of surfaces combining stable superhydrophobicity and high transparency with particularly low haze remains a challenge. Here, we demonstrate a nonfluorinated hierarchical surface, simply prepared by sequential spraying of a primer of poly(ethylene- co -acrylic acid) (EAA) and silica nanoparticles (SiO 2 ). The resultant surface shows remarkable liquid repellency (e.g., an apparent contact angle of >160° and a sliding angle of <2° for honey) and high transparency (a transmittance of ∼91% and a haze of ∼6%). Especially, flexible EAA adhesive enables the surface to resist water impinging (up to ∼15.0 m s -1 , higher than the terminal velocities of raindrops) and mechanical damaging. This super-repellent surface also presents excellent UV and chemical stability, sustaining a superhydrophobic state upon UVA exposure for 60 days and acidic corrosion or oil contamination for 7 days. With multirobustness and scalability, our coatings show great potential in related fields.

The fast recombination of photogenerated charge carriers and poor stability have impeded the application of many narrow band gap semiconductors with otherwise excellent photocatalytic performance. A metal-semiconductor Schottky junction is a promising strategy to accelerate charge separation and enhance catalytic efficiency. However, the preparation of these structures often involves intricate processes and harsh conditions, which will inevitably destroy the electronic structures of the semiconductors and ruin their original properties in practical applications. In this study, a reduced graphene oxide (RGO)-enwrapped Cu-Cu 2 O nanocomposite (Cu-Cu 2 O@RGO) spontaneously evolved from an aqueous alcoholic solution containing cupric ions and graphene oxide (GO) under simulated sunlight irradiation. During this process, GO reduction and Cu-Cu 2 O nanoparticles growth occurred simultaneously in conjunction with in situ RGO encapsulation. Benefiting from the superior intrinsic semiconductor characteristic retention under mild reaction conditions, strong component interactions, and efficient interfacial charge transfer, the distinctive Cu-Cu 2 O@RGO nanocomposite supplied multiple channels for rapid electron transfer to substantially enhance the charge carrier separation efficiency and provide perfect chemical protection to effectively prevent Cu 2 O photocorrosion. This product also greatly suppressed self-aggregation to decrease the size of nanoparticles. Based on these merits, the Cu-Cu 2 O@RGO nanocomposite offered promising advances in photoelectrochemical and photocatalytic H 2 evolution. This work provides an innovative photoinduced strategy for constructing an RGO-enwrapped semiconductor nanocomposite with efficient charge transfer interfaces while providing novel insights for the efficient solar energy utilization.

Due to the special framework structure, ZIF-67 is a promising material as the precursor to prepare the Co@C catalysts with high cobalt loading and superior cobalt dispersion. Unfortunately, these Co@C- X catalysts exhibit not only unsatisfied activity but also high CH 4 selectivity. This limited its further application due to the lack of in-depth analysis of the reasons behind it. In this work, the Co@C- X catalysts were prepared by pyrolyzing the ZIF-67 precursor at different temperatures. A series of characterizations were conducted to explore the behavior of the graphite carbon coated on cobalt species, realizing that the role of active Co sites on these Co@C catalysts was restricted by the graphite carbon layer since it suppressed the adsorption and activation of syngas on Co sites. TEOS was introduced to suppress the aggregation of cobalt species and more active sites were exposed after the graphite carbon layer was eliminated. As a result, the FTS performance was greatly improved by a factor of 5. The effect of O 2 concentration on the microcrystalline size of Co and the reconfinement effect of SiO 2 were investigated. The model catalyst was prepared and the key factors determining CH 4 selectivity of the ZIF-67-derived Co@C catalyst were revealed. This provides a good basis for rational designing ZIF-67-derived Co-based FTS catalysts.

As a critical component in perovskite solar cells (PSCs), hole-transporting materials (HTMs) have been extensively explored. To develop efficient dopant-free HTMs for PSCs, a decent hole mobility (>10 -3 cm 2 V -1 s -1 ) is critically essential, which is, however, seldom reported. In this work, we introduce two novel donor-acceptor (D-A) type conjugated polymers ( PDTPC-1 and PDTPC-2 ) with narrow bandgap unit, i.e., fused dithienopicenocarbazole ( DTPC ), as the donor building block and benzo[ c ][1,2,5]thiadiazole derivatives as the acceptors. The highly planar and strong electron-donating DTPC endows the polymers with superior hole mobility up to ∼4 × 10 -3 cm 2 V -1 s -1 . Because of the better energy alignment with perovskite and excellent film-forming property, PSCs with PDTPC-1 as HTM show an appreciably enhanced PCE of ∼17% in dopant-free PSCs along with improved device stability as opposed to PDTPC-2 . Our work revealed for the first time that the introduction of narrow bandgap DTPC in D-A polymers could achieve remarkably high hole mobility in the pristine form, favoring the application in dopant-free PSCs.

The construction of a single polymer network with extreme stretchability, relatively high mechanical strength, and fast and facile autonomous room-temperature self-healing capability still remains a challenge. Herein, supramolecular polymer networks are fabricated by synergistically incorporating metal-ligand and hydrogen bonds in poly(propylene glycol) (PPG). The representative specimen, PPG-Im-MDA-1.5-0.25-Cu, shows a combination of notable mechanical properties involving an extreme stretching ratio of 346 ± 14× and a Young's modulus of 2.10 ± 0.14 MPa, which are superior to the previously reported extremely stretchable polymeric materials. Notably, the destroyed specimen can fully recover mechanical performances within 1 h. The tunability of mechanical properties and self-healing capability has been actualized by merely tailoring the content of a chain extender. The application of the as-prepared supramolecular PPG network in constructing a flexible and self-healable conductor has been demonstrated. This strategy provides some insights for preparing extremely stretchable and self-healable polymeric materials.

Solid-state batteries with alkali metals (Li, Na, etc.) as anodes have the potential to achieve high energy density. However, the Li penetration through the garnet occurs without preindication during electrochemical cycling, leading to sudden short circuit and safety concerns. Various improvement strategies are developed but such a problem still exists when the current density exceeds the critical value. In contrast, the electrochemical Na plating/stripping on the β″-alumina ceramic electrolyte (BASE) has been explored with improved interfacial contacts by introducing an Au intermediate layer. When being cycled around the critical current density, the polarization potential of the Na/Au/BASE symmetric cells increases progressively until it stabilizes at a certain value without the sudden short circuit. It is revealed that the increasing polarization originates from a gradual Na penetration into the BASE ceramics from the interface and the subsequent stable cycles correlate with the formation of a sustainable Na/Au/BASE interface. These results disclose the difference in a growth model of metal filaments through Li and Na solid electrolytes, shedding new light on understanding of the metal penetration in solid electrolytes.

Flexible membrane electrolytes consisting of Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) fillers in poly(propylene carbonate) (PPC) are considered promising for developing solid lithium batteries with high energy density and safety. However, LLZTO particles tend to agglomerate owing to their high surface energy, especially concerning their distribution in PPC that has low surface energy. Moreover, basic LLZTO particles attack PPC, resulting in its decomposition. Such problems make it difficult to achieve membrane electrolytes of PPC/LLZTO with high conduction and stability. In this work, continuous polydopamine (PDA) layers with a thickness of 4 nm are coated on LLZTO particles. Characterized by synchrotron X-ray microtomography and scanning electron microscopy, the PDA-coated LLZTO particles show homogeneous dispersion in PPC, which is attributed to the reduced surface energy of the LLZTO particles. Besides, this coating hinders the reaction between LLZTO and PPC, which improves the chemical stability of the membrane electrolytes. Consequently, the cells based on membrane electrolytes with PDA-coated LLZTO particles in PPC show improved electrochemical performance and cycling stability. These results demonstrate that the strategy of coating basic LLZTO particles is powerful for enhancing their usability in the high-performance membrane electrolytes for solid lithium batteries.

The demand for solid lithium batteries with high energy density and safety boosts the development of solid-state electrolytes in which composite membrane electrolytes consisting of polymers and ceramic fillers are attractive. As the common ceramic filler, perovskite-structured Li 0.33 La 0.557 TiO 3 (LLTO) has great advantage on cost and environmental friendliness by using earth-abundant raw materials in the production. Nevertheless, the chemical instability of LLTO against Li-metal hinders its application. Herein, LLTO particles are coated by biodegradable polydopamine (PDA) layers and united with poly(vinylidene fluoride) (PVDF) to prepare composite electrolytes which perform superior stability against Li-metal. Besides, PVDF:LLTO membranes are assembled at cathode sides and show high voltage tolerance. The Li/Ni 0.6 Mn 0.2 Co 0.2 O 2 cells with bilayer membrane electrolytes can deliver the specific capacity of 158.2 mAh g -1 and maintain 83% capacity after 100 cycles at 0.1 C. Furthermore, based on the bilayer membranes with outstanding flexibility and stretchability, the cells can even survive under several extreme conditions, such as bending, twisting, crimping, and stretching. This study offers an environmentally friendly strategy to improve the stability of LLTO against Li and sheds light on the development of cost-effective solid electrolytes.

Low-temperature solution-processed methylammonium lead iodide (MAPbI 3 ) crystalline films have shown outstanding performance in optoelectronic devices. However, their high dark current and high noise equivalent power prevent their application in broad-band photodetectors. Here, we applied a facile solution-based antisolvent strategy to fabricate a hybrid structure of CuInSe 2 quantum dots (CISe QDs) embedded into a MAPbI 3 matrix, which not only enhances the photodetector responsivity, showing a large on/off ratio of 10 4 at 2 V bias compared with the bare perovskite films, but also significantly (for over 7 days) improves the device stability, with hydrophobic ligands on the CuInSe 2 QDs acting as a barrier against the uptake of environmental moisture. MAPbI 3 /CISe QD-based lateral photodetectors exhibit high responsivities of >0.5 A/W and 10.4 mA/W in the visible and near-infrared regions, respectively, partly because of the formation of a type II interface between the respective semiconductors but most significantly because of the efficient trap-state passivation of the perovskite grain surfaces, and the reduction in the twinning-induced trap density, which stems from both CISe QDs and their organic ligands. A large specific detectivity of 2.2 × 10 12 Jones at 525 nm illumination (1 μW/cm 2 ), a fast fall time of 236 μs, and an extremely low noise equivalent power of 45 fW/Hz 1/2 have been achieved.

Mesenchymal stem cells (MSCs) have a very low survival rate after in vivo delivery, which limits their great promise for treating human diseases. Various strategies have been studied to overcome this challenge. However, an overlooked but important potential is to apply exogenous signaling molecules as biochemical cues to promote MSC survival, presumably because it is well-known that MSCs themselves can release a variety of potent signaling molecules. Thus, the purpose of this work was to examine and understand whether the release of exogenous signaling molecules from hydrogels can promote the survival of MSC spheroids. Our data show that more vascular endothelial growth factor (VEGF) but not platelet-derived growth factor BB (PDGF-BB) were released from MSC spheroids in comparison with 2D cultured MSCs. Aptamer-functionalized fibrin hydrogel (aFn) could release exogenous VEGF and PDGF-BB in a sustained manner. PDGF-BB-loaded aFn promoted MSC survival by ∼70% more than VEGF-loaded aFn under the hypoxic condition in vitro. Importantly, PDGF-BB-loaded aFn could double the survival rate of MSC spheroids in comparison with VEGF-loaded aFn during the one-week test in vivo. Therefore, this work demonstrated that defined exogenous signaling molecules (e.g., PDGF-BB) can function as biochemical cues for promoting the survival of MSC spheroids in vivo.

Energy-saving cooling materials with strong operability are desirable for sustainable thermal management. Inspired by the cooperative thermo-optical effect in the fur of a polar bear, we develop a flexible, superhydrophobic, and reusable cooling "skin" by laminating a poly(dimethylsiloxane) film with a highly scattering polyethylene aerogel. Owing to its high porosity (97.9%) and tailored pore size of 3.8 ± 1.4 μm, it can achieve superior solar reflectance ( R ̅ sun ∼ 0.96) and high transparency to irradiated thermal energy (τ̅ PE,MIR ∼ 0.8) at a thickness of 2.7 mm. Combined with the low thermal conductivity (0.032 W m -1 K -1 ) of the aerogel, the cooling skin exerts midday sub-ambient temperature drops of 5-6 °C in a metropolitan environment, with an estimated limit of 14 °C under ideal service conditions. Our generalized bilayer approach can be easily applied to different types of emitters, bridging the gap between night-time and daytime radiative cooling and paving the way for more cost-effective and scalable cooling materials.

Electrolyte solutions and electrode active materials, as core components of energy storage devices, have a great impact on the overall performance. Currently, supercapacitors suffer from the drawbacks of low energy density and poor cyclic stability in typical alkaline aqueous electrolytes. Herein, the ultrathin Co 3 O 4 anode material is synthesized by a facile electrodeposition, followed by postheat treatment process. It is found that the decomposition of active materials induces reduction of energy density and specific capacitance during electrochemical testing. Therefore, a new strategy of preadding Co 2+ cations to achieve the dissolution equilibrium of cobalt in active materials is proposed, which can improve the cyclic lifetime of electrode materials and broaden the operation window of electrochemical devices. Co 2+ and Li + embedded in carbon electrode during charging can enhance H + desorption energy barrier, further hampering the critical step of bulk water electrolysis. More importantly, the highly reversible chemical conversion mechanism between Co 3 O 4 and protons is demonstrated to be the fact that a large amount of quantum dots and second-order flaky CoO layers were in situ formed in the electrochemical reaction process, which is first discovered and reported in neutral solutions. The as-assembled device achieves a high operation voltage (2.2 V), excellent cycling stability (capacitance retention of 168% after 10 000 cycles) and ultrahigh energy density (99 W h kg -1 at a power density of 1100 W kg -1 ). The as-prepared electrolytes and highly active electrode materials will open up new opportunities for aqueous supercapacitors with high safety, high voltage, high energy density, and long-lifespan.

Developing high-performance Li-S batteries with high sulfur loading is highly desirable for practical application and remains a major challenge. To achieve this goal, the following requirements for designing carbon/metal compound composites need to be met: (i) the carbon materials need to exhibit suitable specific surface area, void structure, and electrical conductivity; (ii) the weight content of the metal compounds should be low; and (iii) the metal compounds need to show a strong adsorption and efficient electrocatalytic function for LiPSs. In this study, inspired by the body structure of an octopus, a new carbon/NiS 2 hierarchical composite is reported, in which the apical NiS 2 nanoparticles (0D) on a 1D carbon nanotubes (CNTs) are supported on a three-dimensional carbon (3DC) framework (3DC-CNTs-NiS 2 ). The 3DC-CNTs-NiS 2 composite has a high specific surface area (271 m 2 g -1 ), good electrical conductivity, and low NiS 2 content (9.2 wt %), and the apical NiS 2 nanoparticles are capable of adsorption and electrocatalysis toward LiPSs, demonstrated by both electrochemical characterization and theoretical calculation. When used as a cathode host of the Li-S battery, it exhibits an ultra-stable cycling performance with a fade rate of 0.043% per cycle over 1000 cycles; even with a high S loading (6.5 mg cm -2 with 90 wt % of S), the soft package battery delivers a high area capacity of 5.0 mAh cm -2 under the E/S ratio of 5 μL E mg -1 s . This work provides a new approach to design and fabricate multi-functional S hosts with high S loading.

Efficient and stable electrocatalysts for oxygen reduction reaction and freestanding electrode structure were developed to reduce the use of polymer binders in the cathode of metal-air batteries. Considering the unique geometrical configurations of helical carbon nanotubes (CNTs) and improved properties compared with straight CNTs, we prepared high-purity Co@CoO x /helical nitrogen-doped carbon nanotubes (Co@CoO x /HNCNTs) on a carbon fiber paper by hydrothermal and single-step in situ chemical vapor deposition strategies. Under an optimized growth time (1 h), the synthesized Co@CoO x /HNCNTs provide richer edge defects and active sites and show prominent electrocatalytic performance toward oxygen reduction reaction (ORR) under alkaline media compared with Co@CoO x /HNCNTs-0.5 h and Co@CoO x /HNCNTs-2 h. The soft X-ray absorption spectroscopy technique is used to investigate the influences of different growth times on the electronic structure and local chemical configuration of Co@CoO x /HNCNTs. Furthermore, the Al-air coin cell employing Co@CoO x /HNCNTs-1 h as the binder-free cathode exhibits an open-circuit voltage of 1.48 V, a specific capacity of 367.31 mA h g -1 at the discharge current density of 1.0 mA cm -2 , and a maximum power density ( P max ) of 3.86 mW cm -2 , which are superior to those of Co@CoO x /HNCNTs-0.5 h and Co@CoO x /HNCNTs-2 h electrodes. This work provides valuable insights into the development of scalable binder-free cathodes, exploiting HNCNT composite materials with an outstanding electrocatalytic performance for ORR in Al-air systems.

Polymer-inorganic hybrid nanomaterials have attracted much attention for the multimodal cancer therapy, while it is still desirable to explore hybrids with superior morphologies for two or more therapeutic modalities. In this work, four types of carbon nanoparticles with distinct morphologies were prepared by an elaborate template-carbonization corrosion process and then functionalized with a similar amount of the superior polycationic gene vector, CD-PGEA [consisting of one β-cyclodextrin core (CD) and two cationic ethanolamine-functionalized poly(glycidyl methacrylate) (PGEA) arms] to evaluate the morphology-influenced gene and photothermal (PT) therapy. Benefiting from the starting rough hollow nanosphere (RHNS) core, the resultant nanohybrids RHNS-PGEA exhibited the highest gene transfection (including luciferase, fluorescent protein plasmid, and antioncogene p53) and NIR PT conversion efficiency among the four types of nanohybrids. Moreover, the efficient PT effect endowed RHNS-PGEA with PA imaging enhancement and an effective imaging guide for the tumor therapy. In addition, anticancer drug 10-hydroxy camptothecin was successfully encapsulated in RHNS with polycation coating, which also displayed the second near-infrared (NIR-II)-responsive drug release. Taking advantages of the superior gene delivery/PT effect and NIR-II-enhanced drug delivery, RHNS-PGEA realized a remarkable therapeutic effect of trimodal gene/PT/chemotherapy of malignant breast cancer treatment in vitro and in vivo. The present work offers a promising approach for the rational design of polymer-inorganic nanohybrids with superior morphology for the multimodal cancer therapy.

Fabricating a single polymer network with a combination of a multi-shape memory effect (multiple-SME), solid-state plasticity, recyclability and self-healing behavior remains a challenge. We designed imine bond and ionic hydrogen bond dual cross-linked polybutadiene (PB) networks. The resulting PB networks showed a triple-shape memory effect, where imine bonds could be used to fix the permanent shape and ionic hydrogen bonds and glass transition acted as the transition segments for fixing/releasing the temporary shapes. Additionally, the dual dynamic bonds offered PB networks outstanding solid-state plasticity, recyclability and self-healing behavior. This strategy provides some insights for preparing shape memory polymers integrating multiple-SME and multi-functionality.

Injectable and self-healing hydrogels with thermoresponsiveness as smart hydrogels displayed injectability, automatic healing, and phase and volume changes as well. Here, the thermoresponsive self-healing hydrogel was prepared via the formation of dynamic covalent enamine bonds between the amino groups in polyetherimide (PEI) and the acetoacetate groups in the four-armed star-shaped poly(2-(dimethylamino)ethyl methacrylate- co -2-hydroxyethyl methacrylate) modified with tert -butyl acetoacetate ( t -BAA), SP(DMAEMA- co -HEMA-AA). After adding polydopamine nanoparticles (PDA NPs), the SP(DMAEMA- co -HEMA-AA)/PEI/PDA-NP nanocomposite hydrogel presented phase change and volume shrinkage under near-infrared (NIR) irradiation. The thermoresponsive nanocomposite hydrogel loaded with the anticancer drug doxorubicin (DOX) could be injected into the 4T1 tumor by intratumoral injection. After NIR laser irradiation, the temperature of the hydrogel increased because of the photothermal effect of PDA NPs inducing local hyperthermia. Because the hydrophilicity-hydrophobicity transition of the hydrogel occurred, DOX molecules were squeezed out from the hydrogel at temperatures higher than its lower critical solution temperature (LCST) and the tumor cells suffered from internal stress from the shrunk hydrogel. The injectable nanocomposite hydrogel not only demonstrated the synergism of highly efficient thermochemotherapy but also showed the function of improving drug utilization and precise treatment to reduce the side effects of drugs.

The intrinsic properties of photocatalysts, such as electron state and energy band structure, contribute significantly to their catalytic performance. However, it is difficult to alter these properties of semiconductors by conventional modifications. To adjust the intrinsic properties while preserving long-term conjugation of the polymeric photocatalysts, a post-thermal treatment is proposed to codope P and Na into polymeric carbon nitride in this work. After codoping, the absorption of visible irradiation is strongly extended up to 639 nm. Additionally, the lifetime of charge carriers is almost tripled from 1.09 to 2.93 ns. The photocatalytic hydrogen evolution performance under visible light is improved to 2032 μmol·h -1 g -1 in the optimized sample, corresponding to apparent quantum efficiencies of 6.79% and 0.09% at 420 and 600 nm, respectively. The enhanced catalytic activity is ascribed to the synergistic effects of prolonged lifetime and increased charge density that resulted from lattice distortion and extended visible utilization due to the formation of subgap state. Our work provides new pathways for the modification of polymeric catalysts toward high-performance and full-spectrum photocatalysis.

Fluorescent materials with advanced functionalities provide powerful tools to visualize subcellular microstructures and monitor subcellular dynamic functions, which significantly boost our understanding of complex biological phenomena and manipulation of biological behaviors. However, realization of diverse biological applications from a single molecular backbone is still a challenging endeavor. In this contribution, a series of coumarin-based cationic fluorophores ( Cou-n , n = 1-4) with near-infrared emission (675 nm) and large Stokes shifts (110 nm) have been developed. Considering their excellent biocompatibilities and alkyl chain-dependent lipophilicities, Cou-1 and Cou-3 could selectively and ultrafast (<30 s) stain the cell plasma membrane and mitochondria in a washing-free manner, respectively. Meanwhile, Cou-1 could sensitively respond to the change of the plasma membrane potential, which enabled Cou-1 to successfully indicate the cell passage number. Taking advantage of specific mitochondria targeting as well as efficient singlet oxygen generation, Cou-3 exhibited enhanced photodynamic therapy (PDT) effect for tumor inhibition in vivo. In addition, the suitable lipophilicity of Cou-3 aided it in selectively imaging Gram-positive bacteria and efficiently killing bacteria by the PDT process.

In this paper, a series of Cu-Zr mixed metal oxide-supported Au catalysts were prepared by deposition-precipitation and evaluated for selective oxidation of glycerol to dihydroxyacetone (DHA) in base-free conditions. The best catalytic performance was obtained with DHA selectivity of up to 95% and yield of 70% in 4 h, 50 °C and P O 2 = 0.2 MPa over the Au/Cu 0.95 Zr 0.05 and Au/Cu 0.9 Zr 0.1 catalysts. Combined with the characterization results of Brunauer-Emmett-Teller, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and CO 2 temperature programmed desorption, it was proposed that the content of Au 0 , the size of Au, and the basicity of the catalyst affected the glycerol conversion and DHA selectivity. After the catalyst was recycled four times, the glycerol conversion decreased by about 14% which might result from the carbon deposition or the byproduct adsorption and the agglomeration of Au particle.

Ceramic phase reinforced aluminum matrix composites (CAMCs) are widely used in high-tech fields represented by aerospace industry due to their advantages of high specific strength, high specific modulus, high thermal stability, and light weight. Strong interface bonding is a prerequisite for high performance of multiphase materials. Herein, a novel CAMC in situ reinforced by MgAl 2 O 4 particles and MgAlB 4 nanorods was prepared by vacuum hot-pressing combined with hot-extrusion process. A high-resolution transmission electron microscope was used to characterize the orientation relationship and interface structure between the ceramic phases and the aluminum matrix. Two orientation relationships (OR1 and OR2) of MgAl 2 O 4 /Al and one (OR3) of MgAlB 4 /Al are determined: OR1-[011] p //[011] Al , (11̅1) p //(11̅1) Al ; OR2-[211] p //[011] Al , (113̅) p //(022̅) Al ; OR3-[101̅0] R //[001] Al , (0002) R //(2̅20) Al . The MgAl 2 O 4 in OR1 forms a coherent interface with the aluminum matrix at (111) surface, while they form a 4 × 5 near coincidence site lattice (CSL) interface structure for OR2. In OR3, the MgAlB 4 forms an approximate coherent interface with Al matrix at its (0002) surface and a 2 × 5 CSL interface structure at its (011̅0) surface. First-principles calculations suggest that MgAl 2 O 4 combines to aluminum at (111) plane through covalent bonds, which means high interfacial bonding strength. The hot-extrusion process makes the ceramic phase evenly distributed in the matrix. The mechanical properties of the composites are greatly improved compared with pure aluminum.

Exploring highly efficient catalysts for the electrochemical hydrogen evolution reaction (HER) is highly demanded in the sustainable production of hydrogen. MoS 2 is recognized as a potential candidate catalyst for HER, but its active site is mainly located at the edges, which is extremely limited. Here, we have investigated the catalytic performance of HER in the MoS 2 basal planes during the structural transition from the 2H to the 1T' phase. Different kinds of 2H/1T' structural interfaces are considered, and the adsorbed H free energies (Δ G H ) on these surfaces were calculated. The active site for H adsorption is on the top of S atoms at the 2H/1T' phase boundary. The zigzag 2H/1T' interfaces exhibit an optimal performance for the Volmer reaction with the Δ G H being very close to zero. The Volmer-Heyrovsky reaction is dominantly preferred to the Volmer-Tafel reaction. Our study provides a new picture to boost up the active sites of the basal plane for HER on MoS 2 , and this electrocatalytic mechanism is also applicable for other transition metal dichalcogenide materials.

Colorectal cancer (CRC) is now one of the leading causes of cancer incidence and mortality. Although nanomaterial-based drug delivery has been used for the treatment of colorectal cancer, inferior targeting ability of existing nanocarriers leads to inefficient treatment and side effects. Moreover, the majority of intravenously administered nanomaterials aggregate into the reticuloendothelial system, leaving a certain hidden risk to human health. All those problems gave great demands for further construction of well-performed and biocompatible nanomaterials for in vivo theranostics. In the present work, from a biomimetic point of view, Lactobacillus reuteri biofilm (LRM) was coated on the surface of trackable zinc gallogermanate (ZGGO) near-infrared persistent luminescence mesoporous silica to create the bacteria bioinspired nanoparticles (ZGGO@SiO 2 @LRM), which hold the inherent capability of withstanding the digestion of gastric acid and targeted release 5-FU to colorectum. Through the background-free persistent luminescence bioimaging of ZGGO, the coating of LRM facilitated the localization of ZGGO@SiO 2 @LRM to the tumor area of colorectum for more than 24 h after intragastric administration. Furthermore, ZGGO@SiO 2 @LRM hardly entered the blood, which avoided possible damage to immune organs such as the liver and spleen. In vivo chemotherapy experiment demonstrated the number of tumors per mouse in ZGGO@SiO 2 @LRM group decreased by one-half compared with the 5-FU group ( P < 0.001). To sum up, this LRM bioinspired nanoparticles could tolerate the digestion of gastric acid, avoid aggregation by the immune system, favor gut-oriented drug delivery, and targeted release oral 5-FU into colorectum for more than 24 h, which may give new application prospects for targeted delivery of oral drugs into the colorectum.

It is of great significance to develop biocompatible and degradable gene carriers with stimuli-enhanced gene therapy and imaging function. In this work, low-cytotoxic polycation PGEA (ethanolamine-functionalized poly(glycidyl methacrylate))-functionalized dextran-quantum dot (QD) nanohybrids (DQ-PGEA) were proposed as safe and efficient gene carriers via a facile and feasible method. The highly water-soluble dextran gives the carrier good stability, biocompatibility, and abundant modification sites, while QDs allow fluorescence (FL) imaging. Taking advantage of the pH-responsive self-destruction characteristic introduced by Schiff base linkages, DQ-PGEA nanohybrids could not only result in enhanced gene release but also contribute to the elimination of the carriers. Reduced (nondegradable) DQ-PGEA-R nanohybrids were also synthesized as counterparts to reveal the superiority of the responsive DQ-PGEA carriers. The effectiveness of the as-prepared gene delivery systems was verified adopting the antioncogene p53 in the mouse model of breast cancer. As expected, DQ-PGEA nanohybrids demonstrated a superior gene transfection performance and antitumor inhibition compared with their counterparts. Meanwhile, the gene delivery processes could be tracked in real time to visualize the therapeutic processes and realize FL imaging-guided gene therapy. The current multifunctional stimuli-responsive nanoplatforms with the self-destruction feature are intriguing candidates to achieve enhanced gene therapy for tumor treatment.

A series of NiCo 2 P-based electrocatalysts, which were wrapped by CeO 2 whose oxygen vacancies (V O ) are partially filled with phosphorus atoms (named as NiCo 2 P x /P x FVo-CeO 2 , where x refers to the consumption of NaH 2 PO 2 ·H 2 O), have been fabricated to improve the electrocatalytic reactivity of NiCo 2 P toward hydrogen evolution in alkaline solution. In the novel catalysts, the P atoms fill the oxygen vacancies, elevate the chemical valence state of Ni 2+ and Co 3+ , and increase the hydride acceptors, which reinforcing the promoting effect of CeO 2 in the hydrogen evolution reaction (HER). Moreover, the negatively charged P atoms capture the positively charged protons more easily, benefiting the Volmer step during HER. Furthermore, the synergistic effect between oxygen vacancies and the filled P atoms accelerates the migration rate of electrons/ions and increases the electrochemical active area. All of the above are advantageous to the hydrogen evolution of NiCo 2 P x /P x FVo-CeO 2 in alkaline electrolyte. As a result, the overpotential as low as 33.6 mV is achieved for NiCo 2 P 0.3 /P 0.3 FVo-CeO 2 in alkaline media to drive a current density of 10 mA cm -2 . The reactivity is superior to that of Pt/C at a large current density along with a Tafel slope of 61.24 mV dec -1 and long-term durability, which giving a new technology for efficient transition-metal catalyst candidates toward HER in alkaline solution.

Recently, loading TiO 2 with transition-metal disulfides (TMDs) to construct dual functional heterostructures has been widely researched as an effective strategy to improve the photocatalytic performance of a TiO 2 photocatalyst. For the TMD cocatalysts, the 2H-MoS 2 and 1T-MoS 2 have been widely studied and researched. However, they suffer from poor catalytic activity sites/low charge transfer ability and an unstable structure. In this regard, distorted 1T-phase TMDs with a stable structure are greatly fit for the cocatalyst due to their high charge transfer ability and rich catalytic sites on both the edge and basal plane. Therefore, it is highly desirable to develop distorted 1T-phase TMD/TiO 2 heterostructures with well-identified interfaces for highly enhanced photocatalytic performance. Herein, we first introduce distorted 1T-ReS 2 anchored on porous TiO 2 nanofibers as a promising photocatalyst for achieving an excellent photocatalytic hydrogen production. The excellent performance is attributed to the strong chemical interaction of the Ti-O-Re bond between TiO 2 and ReS 2 , the excellent electron mobility of distorted 1T-ReS 2 , and the abundant catalytic activity sites on both the plane and edge of the ReS 2 cocatalyst.