Stabilizing Anode-Electrolyte Interface for Dendrite-Free Zn-Ion Batteries Through Orientational Plating with Zinc Aspartate Additive.

The stability of aqueous Zn-ion batteries (AZIBs) is detrimentally influenced by the formation of Zn dendrites and the occurrence of parasitic side reactions at the Zn metal anode (ZMA)-electrolyte interface. The strategic manipulation of the preferential crystal orientation during Zn2+ plating serves as an essential approach to mitigate this issue. Here, Zn aspartate (Zn-Asp), an electrolyte additive for AZIBs, is introduced not only to optimize the solvation structure of Zn2+ , but also to crucially promote preferential Zn2+ plating on the (002) crystal plane of ZMA. As a result, both side reactions and Zn dendrites are effectively inhibited, ensuring an anode surface free of both dendrites and by-products. The implementation of Zn-Asp leads to significant enhancements in both Zn||Zn symmetric and Zn||Ti batteries, which demonstrate robust cyclability of over 3200 h and high Coulombic efficiency of 99.29%, respectively. Additionally, the Zn||NaV3 O8 ·1.5H2 O full battery exhibits remarkable rate capability, realizing a high capacity of 240.77 mA h g-1 at 5 A g-1 , and retains 92.7% of its initial capacity after 1000 cycles. This research underscores the vital role of electrolyte additives in regulating the preferential crystal orientation of ZMA, thereby contributing to the development of high-performing AZIBs.

Experimental Study of Ghost Imaging in Underwater Environment.

Underwater imaging technique is a crucial tool for humans to develop, utilize, and protect the ocean. We comprehensively compare the imaging performance of twenty-four ghost imaging (GI) methods in the underwater environment. The GI methods are divided into two types according to the illumination patterns, the random and orthogonal patterns. Three-group simulations were designed to show the imaging performance of the twenty-four GI methods. Moreover, an experimental system was built, and three-group experiments were implemented. The numerical and experimental results demonstrate that the orthogonal pattern-based compressed sensing GI methods have strong antinoise capability and can restore clear images for underwater objects with a low measurement number. The investigation results are helpful for the practical applications of the underwater GI.

Nano-Sized Calcium Copper Titanate for the Fabrication of High Dielectric Constant Functional Ceramic-Polymer Composites.

A novel calcium copper titanate (CaCu3Ti4O12)-polyvinylidene fluoride composite (CCTO@PVDF) with Cu-deficiency was successfully prepared through the molten salt-assisted method. The morphology and structure of polymer composites uniformly incorporated with CCTO nanocrystals were characterized. At the same volume fraction, the CCTOs with Cu-deficiency displayed higher dielectric constants than those without post-treatment. A relatively high dielectric constant of 939 was obtained at 64% vol% CCTO@PVDF content, 78 times that of pure PVDF. The high dielectric constants of these composites were attributed to the homogeneous dispersion and interfacial polarization of the CCTO into the PVDF matrix. These composites also have prospective applications in high-frequency regions (106 Hz). The enhancement of the dielectric constant was predicted in several theoretical models, among which the EMT and Yamada models agreed well with the experimental results, indicating the excellent distribution in the polymer matrix.

High Capacitive Antimonene/CNT/PANI Free-Standing Electrodes for Flexible Supercapacitor Engaged with Self-Healing Function.

In virtue of the high electrochemical activity and inherent flexibility, polyaniline (PANI) is an ideal electrode material for flexible supercapacitors (SCs). However, in practical applications, the inevitable agglomeration of PANI leads to low capacitance, poor rate performance, and cycling stability. Here, antimonene (Sb) nanosheets with ultrathin thickness, excellent mechanical strength, and flexibility are introduced into the carbon nanotube (CNT) framework for PANI electrodeposition via simple vacuum filtration, which enables the continuous and uniform growth of PANI. The resultant free-standing Sb/CNT/PANI electrode can thus exhibit a high specific capacitance of 578.57 F g-1 together with a high rate capability. Besides, thanks to the introduction of Sb nanosheets, the agglomeration of PANI during the electrodeposition is improved, which correspondingly alleviates the structural deterioration of PANI during repeated charge/discharge. Thus, the flexible SC assembled by Sb/CNT/PANI electrodes demonstrates both an impressive specific capacitance of 416 F g-1 and outstanding cycling stability over 12 000 cycles. Moreover, this SC device can have a practical self-healing function by employing self-healable polyurethane. The facile strategy reported herein sheds light on the design of high-performance flexible SCs, catering to the needs of portable and wearable electronics.

ZIF-67 Derivative Decorated MXene for a Highly Integrated Flexible Self-Powered Photodetector.

The rapid development of portable and wearable electronics has promoted the integration of multifunction techniques. Although flexible energy storage systems have been successfully investigated, the compact configuration with photodetector and energy storage components has received less attention. As a new member of the 2D material class, MXene exhibits remarkable electronic and optical properties. Here, through the intentional introduction of ZIF-67 derivatives deposited on the Mo2CTx nanosheets, the synthesized Co-CoOx/NC/Mo2CTx heterostructure not only provided a straightforward pathway for photogenerated electrons to transport but also enhanced the structural stability of Mo2CTx, leading to a high responsivity and short rise/decay time under the illumination of simulated light in the photoelectrochemical (PEC) configuration. The integrated flexible device based on a zinc ion battery and Co-CoOx/NC/Mo2CTx heterostructure shows outstanding photodetection function and retains the intrinsic charge/discharge behaviors, which could monitor 1 day sunlight changes in real time. The paradigm presented here paves the way for realizing the development of miniaturization and multifunction toward next-generation portable and wearable technologies.

Interplay between Charge-Density-Wave, Superconductivity, and Ferromagnetism in CuIr2-xCrxTe4 Chalcogenides.

We report the crystal structure, charge-density-wave (CDW), superconductivity (SC), and ferromagnetism (FM) in CuIr2-xCrxTe4 (0 ≤ x ≤ 2) chalcogenides. Powder x-ray diffraction (PXRD) results reveal that the CuIr2-xCrxTe4 series are distinguished between two structural types and three different regions: (i) layered trigonal structure region, (ii) mixed phase regions, and (iii) spinel structure region. Besides, Cr substitution for Ir site results in rich physical properties including the collapse of CDW, the formation of dome-shaped like SC, and the emergence of magnetism. Cr doping slightly elevates the superconducting critical temperature (Tsc) to its highest Tsc = 2.9 K around x = 0.06. As x increases from 0.3 to 0.4, the ferromagnetic Curie temperature (Tc) increases from 175 to 260 K. However, the Tc remains unchanged in the spinel range of 1.9 ≤ x ≤ 2. This finding provides a comprehensive material platform for investigating the interplay between CDW, SC, and FM multipartite quantum states.

Superconducting dome associated with the suppression and re-emergence of charge density wave states upon sulfur substitution in CuIr2Te4chalcogenides.

We report the path from the charge density wave (CDW)-bearing superconductor CuIr2Te4to the metal insulator transition (MIT)-bearing compound CuIr2S4by chemical alloying with the gradual substitution of S for Te. The evolution of structural and physical properties of the CuIr2Te4-xSx(0 ⩽x⩽ 4) polycrystalline system is systemically examined. The x-ray diffraction (XRD) results imply CuIr2Te4-xSx(0 ⩽x⩽ 0.5) crystallizes in a NiAs defected trigonal structure, whereas it adapts to the cubic spinel structure for 3.6 ⩽x⩽ 4 and it is a mixed phase in the doping range of 0.5

Underwater compressive computational ghost imaging with wavelet enhancement.

We propose a compressive Hadamard computational ghost imaging (CGI) method to restore clear images of objects in the underwater environment. We construct an underwater CGI system model and develop a total variation regularization prior-based compressed-sensing algorithm for the CGI image reconstruction. We design a wavelet enhancement algorithm to further denoise and enhance the quality of the CGI image. We build an experimental setup and implement a series of experiments. The effectiveness and advantages of the proposed method are experimentally investigated. The results show that the proposed method can achieve clear imaging for underwater objects with a sub-Nyquist sampling ratio. The proposed method is helpful for improving the image quality of the underwater CGI.

Elimination of Uremic Toxins by Functionalized Graphene-Based Composite Beads for Direct Hemoperfusion.

Conventional absorbents for hemoperfusions suffer from low efficiency and slow absorption with numerous side effects. In this research, we developed cellulose acetate (CA) functionalized graphene oxide (GO) beads (∼1.5-2 mm) that can be used for direct hemoperfusion, aiming at the treatment of kidney dysfunction. The CA-functionalized GO bead facilitates adsorption of toxins with high biocompatibility and high-efficiency of hemoperfusion while maintaining high retention for red blood cell, white blood cells, and platelets. Our in vitro results show that the toxin concentration for creatinine reduced from 0.21 to 0.12 µM (p < 0.005), uric acid from 0.31 to 0.15 mM (p < 0.005), and bilirubin from 0.36 to 0.09 mM (p < 0.005), restoring to normal levels within 2 h. Our in vivo study on rats (Sprague-Dawley, n = 30) showed that the concentration for creatinine reduced from 83.23 to 54.87 µmol L-1 (p < 0.0001) and uric acid from 93.4 to 54.14 µmol L-1 (p < 0.0001), restoring to normal levels within 30 min. Results from molecular dynamics (MD) simulations using free-energy calculations reveal that the presence of CA on GO increases the surface area for adsorption and enhances penetration of toxins in the binding cavities because of the increased electrostatic and van der Waals force (vdW) interactions. These results provide critical insight to fabricate graphene-based beads for hemoperfusion and to have the potential for the treatment of blood-related disease.

Comparative Toxic Effects of Manufactured Nanoparticles and Atmospheric Particulate Matter in Human Lung Epithelial Cells.

Although nanoparticles (NPs) have been used as simplified atmospheric particulate matter (PM) models, little experimental evidence is available to support such simulations. In this study, we comparatively assessed the toxic effects of PM and typical NPs (four carbonaceous NPs with different morphologies, metal NPs of Fe, Al, and Ti, as well as SiO2 NPs) on human lung epithelial A549 cells. The EC50 value of PM evaluated by cell viability assay was 148.7 µg/mL, closest to that of SiO2 NPs, between the values of carbonaceous NPs and metal NPs. All particles caused varying degrees of reactive oxygen species (ROS) generation and adenosine triphosphate (ATP) suppression. TiO2 NPs showed similar performance with PM in inducing ROS production (p < 0.05). Small variations between two carbonaceous NPs (graphene oxides and graphenes) and PM were also observed at 50 µg/mL. Similarly, there was no significant difference in ATP inhibition between carbonaceous NPs and PM, while markedly different effects were caused by SiO2 NP and TiO2 NP exposure. Our results indicated that carbonaceous NPs could be served as potential surrogates for urban PM. The identification of PM model may help us further explore the specific roles and mechanisms of various components in PM.

In Situ Growth of MAPbBr3 Nanocrystals on Few-Layer MXene Nanosheets with Efficient Energy Transfer.

The performance of perovskite nanocrystals (NCs) in optoelectronics and photocatalysis is severely limited by the presence of large amounts of crystal boundaries in NCs film that greatly restricts energy transfer. Creating heterostructures based on perovskite NCs and 2D materials is a common approach to improve the energy transport at the perovskite/2D materials interface. Herein, methylamine lead bromide (MAPbBr3 , MA: CH3 NH3 + ) perovskite NCs are homogeneously deposited on highly conductive few-layer MXene (Ti3 C2 Tx ) nanosheets to form heterostructures through an in situ solution growth method. An optimal mixed solvent ratio is essential to realize the growth of perovskite NCs on Ti3 C2 Tx nanosheets. Time-resolved photoluminescence spectroscopy, transient absorption spectroscopy, and the photoresponse of electron- and hole-only photoelectric conversion devices reveal the interfacial energy transfer behavior within MAPbBr3 /Ti3 C2 Tx heterostructures. The present investigation may provide a useful guide toward use of halide perovskite/2D material heterostructures in applications such as photocatalysis as well as optoelectronics.

Hierarchical Porous RGO/PEDOT/PANI Hybrid for Planar/Linear Supercapacitor with Outstanding Flexibility and Stability.

Many hybrid electrodes for supercapacitors (SCs) are a reckless combination without proper structural design that keeps them from fulfilling their potential. Herein, we design a reduced graphene oxide/poly(3,4-ethylenedioxythiophene)/polyaniline (RGO/PEDOT/PANI) hybrid with hierarchical and porous structure for high-performance SCs, where components fully harness their advantages, forming an interconnected and conductive framework with substantial reactive sites.Thus, this hybrid achieves a high capacitance of 535 F g-1 along with good rate capability and cyclability. The planar SC based on this hybrid deliver an energy density of 26.89 Wh kg-1 at a power density of 800 W kg-1. The linear SC developed via modifying a cotton yarn with the hybrid exhibits good flexibility and structural stability, which operates normally after arbitrary deformations. This work provides a beneficial reference for developing SCs.

Watt-level passively mode-locked Tm:YLF laser at 1.83 µm.

Passive, continuous-wave mode-locked (CWML) operation of a 1.83 µm Tm:YLF laser is experimentally demonstrated for the first time, to the best of our knowledge. Two specially selected output couplers are used to realize this operation. Stability of the CWML laser is obtained with a commercial semiconductor saturable absorber mirror. The maximum average output power is 1.04 W with a pulse duration of 107 ps and repetition rate of 54.1 MHz. Further, a 0.1 mm fused-quartz Fabry-Perot etalon is used to tune the central wavelength of the stable CWML laser at 1827.2 nm, 1829.5 nm, 1831.9 nm, and 1833.5 nm.

A MXene of type Ti3C2Tx functionalized with copper nanoclusters for the fluorometric determination of glutathione.

Luminescent copper nanoclusters (Cu NCs) are chosen to functionalize Ti3C2Tx MXene flakes to form a new kind of nanohybrid. It was applied to the determination of glutathione (GSH) via photoluminescence (PL). The Cu NCs and MXene flakes are in close contact, and the blue PL of the Cu NCs (with excitation/emission peaks at 380/425 nm) is quenched. The addition of GSH triggers the separation of the nanohybrid. This results in the recovery of PL. GSH also promotes the PL of Cu NCs via host-guest interactions. Thus, target recognition, corresponding signal output and further magnification are accomplished in a single step. Under optimum conditions, the nanohybrid can detect GSH in the 5.0 to 100 µM concentration range and with a 3.0 µM detection limit. The assay is very specific and shows high selectivity towards metal ions, small biomolecules, amino acids, and thiol containing molecules. Graphical abstractLuminescent copper nanoclusters are used to functionalize Ti3C2Tx MXene flakes, forming a nanohybrid, which is applied to detect glutathione. Target recognition, signal output and magnification are accomplished in a single step, resulting in high selectivity.

High-power and high-efficiency short wavelength operation of a Tm:YLF laser at 1.83 µm.

A high-power and high-efficiency diode-end-pumped Tm:YLF laser at 1.83 µm is demonstrated for the first time, to our best knowledge. To make the laser operate at 1.83 µm, a simple way of controlling the transmittance of the output coupler is used, and the criteria of the transmittance of the output coupler at the emission peaks of Tm:YLF are theoretically analyzed, which are verified by experimental results. Based on the theoretical analysis, laser oscillation at only 1.83 µm is realized. Maximum output power at 1833 nm is 8.5 W with corresponding slope efficiency of 53.4% regarding absorbed pump power. In addition, tunability of this laser from 1827 nm to 1837 nm is obtained. Laser beam quality at 1833 nm is measured to be 1.4 at maximum output power. The achieved laser performance represents considerable improvement compared to any other bulk laser emitting around 1.83 µm.

Conjugated System of PEDOT:PSS-Induced Self-Doped PANI for Flexible Zinc-Ion Batteries with Enhanced Capacity and Cyclability.

Owing to its electronic conductivity and electrochemical reactivity, polyaniline (PANI) can serve as the cathode for rechargeable zinc-ion batteries (ZIBs). However, it suffers from fast deactivation and thus performance deterioration because of spontaneous deprotonation during charge/discharge. Here, we report an effective strategy to improve the electrochemical reactivity and stability of the PANI-based cathode by constructing a π-electron conjugated system between PANI and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) on carbon nanotubes (CNTs). The impressive performance of the post-treated CNTs-PANI-PEDOT:PSS (t-CNTs-PA-PE) cathode is largely attributed to the -SO3-H+ groups in PSS, which acts as an internal proton reservoir and provides enough H+ for PANI's protonation, thus promoting its electrochemical activity and reversibility. Besides, the strong interactions between PANI and PEDOT:PSS assist the stretching of π-π conjugation chains, bringing about enhanced electronic conductivity. Consequently, the t-CNTs-PA-PE cathode achieves a high capacity of 238 mA h g-1, together with good rate capability and long-term stability (over 1500 cycles with 100% Coulombic efficiency). Through exerting the freestanding t-CNTs-PA-PE, a flexible ZIB was further constructed with both outstanding electrochemical properties and superior high safety. This work demonstrates the availability of conducting polymer cathodes for high-performance ZIBs, fulfilling the need of flexible electronics.

Boosting the Yield of MXene 2D Sheets via a Facile Hydrothermal-Assisted Intercalation.

Ti3C2T x (MXene) exhibits attractive properties in different applications. However, traditional synthesis leads to unsatisfactory yield of two-dimensional (2D) Ti3C2T x, e.g., lower than 20%, which stems from the strong interactions of potential Ti-Ti bonds and residual Ti-Al bonds between the adjacent Ti3C2 layers, hindering the effective intercalation and delamination. Herein, we propose a facile hydrothermal-assisted intercalation (HAI) strategy to boost the yield of 2D sheets, achieving a record high value of 74%. This HAI assists the diffusion and intercalation of reagent effectively, promoting the subsequent delamination; meanwhile, an antioxidant is applied to protect these Ti3C2T x from oxidation during the HAI process. Therefore, massive Ti3C2T x 2D sheets can be easily synthesized. Thanks to the synergistic effect of high conductivity and substantial terminated functionalities, these Ti3C2T x 2D sheets show promising application in supercapacitor, providing a high capacitance of 482 F g-1. Besides, the ultrafast carrier dynamics results of Ti3C2T x 2D sheets clearly imply the promising application in photocatalysis due to the relatively long bleaching relaxation time. Our work not only paves the way for the mass production of Ti3C2T x 2D sheets but also provides insights into their electronic and optical properties.

Ultrathin GeSe Nanosheets: From Systematic Synthesis to Studies of Carrier Dynamics and Applications for a High-Performance UV-Vis Photodetector.

Owing to the attractive energy band properties, a black phosphorus (BP)-analogue semiconductor, germanium selenide (GeSe), shows a promising potential applied for optoelectronic devices. Herein, ultrathin GeSe nanosheets were systematically prepared via a facile liquid-phase exfoliation approach, with controllable nanoscale thickness. Different from BP, ultrathin GeSe nanosheets exhibit good stability under both liquid and ambient conditions. Besides, its ultrafast carrier dynamics was probed by transient absorption spectroscopy. We showed that the GeSe nanosheet-based photodetector exhibits excellent photoresponse behaviors ranging from ultraviolet (UV) to the visible regime, with high responsivity and low dark current. Furthermore, the detective ability of such a device can be effectively modulated by varying the applied bias potential, light intensity, and concentration of the electrolyte. Generally, our present contribution could not only supply fundamental knowledge of a GeSe nanosheet-based photoelectrochemical (PEC)-type device, but also offer guidance to extend other possible semiconductor materials in the application of the PEC-type photodetector.

Hierarchically porous metal-organic frameworks: rapid synthesis and enhanced gas storage.

Large pore sizes, high pore volumes, facile synthesis conditions, and high space-time yields are recognized as four crucial criteria in the fabrication of metal-organic frameworks (MOFs). However, these four objectives are rarely realized together. Herein, we have developed a simple and versatile method that employs 1,4-butanediamine (BTDM) as a template for rapidly fabricating four stable hierarchically porous MOFs (H-MOFs), including HKUST-1, ZIF-8, ZIF-67, and ZIF-90. The synthesis conditions are simple and facile at room temperature and ambient pressure, and the synthesis time can be shortened to 1 min. The resultant H-MOFs exhibit multimodal hierarchically porous structures with meso- and macropores interconnected with micropores, as well as high pore volumes (0.76 cm3 g-1). The maximum space-time yield for the hierarchically porous HKUST-1 reaches 7.4 × 104 kg m-3 d-1, at least one order of magnitude higher than previous reported yields. Notably, the additive BTDM not only facilitates crystal growth but also guides the formation of meso- and macropores. The synthesis route is highly versatile, as analogues (e.g., tetramethyl-1,3-diaminopropane and tetramethyldiaminomethane) can also be employed as templates to prepare diverse H-MOFs. Furthermore, the porosities of the H-MOFs are readily tuned by controlling the metal source, template amount and type of template. The as-synthesized H-MOFs act as adsorbents with significantly improved performances relative to those of microporous MOFs used for CH4 and CO2 gas storage. This strategy may aid in the large-scale industrial synthesis of desirable H-MOFs for gas storage.

In Situ Fabrication of Hierarchical MTW Zeolite via Nanoparticle Assembly by a Tailored Simple Organic Molecule.

Amphiphilic surfactants are widely used as templates to synthesize hierarchically structured zeolites due to their multiple functions; however, piloting such new dual-functional templates is limited by their time-consuming nature and high cost. Herein, a simple organic molecule, without a long hydrophobic alkyl chain, was tailored from a gemini-type, poly-quaternary ammonium surfactant, and effectively used as a dual-porogenic template to synthesize hierarchical MTW zeolite. Upon a range of synthesis parameter optimizations, our detailed characterization suggested that the hierarchical MTW zeolite would completely crystallize within 36 hours from the surface to the inside of quasi-spherical particles through in situ consumption of amorphous silicon and aluminum species; much faster than most of the hierarchical MTW zeolites generated by conventional methods. Moreover, the as-prepared hierarchical MTW zeolite exhibited 4 times higher catalytic performance and lifetime of benzene-propene alkylation compared to conventional MTW zeolite, while the introduced crystalline mesopores are of benefit to diffuse reactants, products, and coke depositions. Our strategy broadens the design of new templates in more effective ways to facilely synthesize versatile hierarchical zeolites for diverse applications, especially for those in which macromolecules are involved.