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Acrylamide (AM) was copolymerized with ethylene glycol dimethacrylate (EGDMA) in the presence of ( R)-1,1′-binaphthalene-2-naphthol (BINOL) as the template molecules on the surface of silica gel by a free radical polymerization to produce a chiral stationary phase based on the surface molecularly imprinted polymer (SMIP-CSP). The SMIP-CSP showed a much better separation factor ( α = 4.28) than the CSP based on the molecularly imprinted polymer (MIP-CSP) without coating on the silica gel ( α = 1.96) during the chiral separation of BINOL enantiomers by high-performance liquid chromatography. The influence of the pretreatment temperature and the content of the template molecule (( R)-BINOL) of the SMIP-CSP, and the mobile phase composition on the separation of the racemic BINOL were systematically investigated. [ABSTRACT FROM AUTHOR]

A distinct “split and recoalescence” growth mechanism of tubular ZnO micro/nanostructures is observed for the first time. On the basis of experimental growth studies and first‐principles calculations, it is proposed that H2/H2O vapor, added to the traditional carbothermal reduction process, changes the intrinsic surface energy of ZnO crystal, which affects the ZnO crystal growth mode and subsequently controls the geometry of ZnO micro/nanotubes. It is shown that these tubular ZnO micro/nanostructures exhibit regular hexagonal cross sections and smooth outer and inner surfaces. Optical studies of ZnO micro/nanotubes reveal characteristic coherent intensity modulations of their emission spectra which reflect the excitation of either whispering gallery modes or wave‐guided modes. The specific type of mode can be selected by controlling the microtube geometry, specifically by its wall thickness to diameter ratio, as demonstrated both experimentally by photoluminescence spectroscopy, and theoretically by finite‐element‐method simulations. [ABSTRACT FROM AUTHOR]

Colloid quantum dots (CQDs) are recognized as an ideal material for applications in next-generation optoelectronic devices, owing to their unique structures, outstanding optical properties, and low-cost preparation processes. However, monodisperse CQDs cannot meet the requirements of stability and collective properties for device applications. Therefore, it is urgent to build stable 3D multiparticle systems with collective physical and optical properties, which is still a great challenge for nanoscience. Herein, we developed a modified microemulsion template method to synthesize quantum dot supraparticles (QD-SPs) with regular shapes and a high packing density, which is an excellent research platform for ultrafast optical properties of composite systems. The redshift of the steady-state fluorescence spectra of QD-SPs compared to CQD solutions indicates that fluorescence resonance energy transfer (FRET) occurred between the CQDs. Moreover, we investigated the dynamic processes of energy transfer in QD-SPs by time-resolved ultrafast fluorescence spectroscopy. The dynamic redshift and lifetime changes of the spectra further verified the existence of rapid energy transfer between CQDs with different exciton energies. In addition, compared with CQD solutions, the steady-state fluorescence lifetime of SPs increased and the fluorescence intensity decreased slowly with increasing temperature, which indicates that the SP structure suppressed the Auger recombination of CQDs. Our results provide a practical approach to enhance the coupling and luminescence stability of CQDs, which may enable new physical phenomena and improve the performance of optoelectronic devices. [ABSTRACT FROM AUTHOR]

This report describes novel pathway for the development of a new type of CSP. A chiral stationary phase (CSP) prepared by coating a molecularly imprinted polymer (MIP) on the surface of silica gel (SMIP-CSP) showed a high separation factor (3.39) in separating racemic 1,1′-binaphthalene-2,2′-diamine (DABN) by high performance liquid chromatography (HPLC). Being the crosslinking agent, ethylene glycol dimethacrylate (EGDMA) was copolymerized with the monomer, methacrylic acid (MAA), in the presence of ( R )-DABN as the template molecules on the surface of the silica gel particles to produce the SMIP-CSPs. The effects of the pretreatment temperature, the ( R )-DABN content and the type of silica gel and monomer in the SMIP-CSPs on the separation of the racemic DABN were systematically investigated. [ABSTRACT FROM AUTHOR]

Single‐crystalline Sb shallow‐doped ZnO microwire wave‐guided optical resonators are synthesized via a simple carbothermal reduction method. The formation of the ZnO wave‐guided microcavities are investigated systematically, and the Sb film formed on the substrate is confirmed to be the critical factor in crystal growth. The optical signals of the annealed ZnO microcavities induced by the Sb related acceptor defects are clarified through a low‐temperature spectrum detection technology. Excitation power and temperature dependence of UV lasing properties of the ZnO microcavities annealed in different atmospheres are studied. The results reveal that such high‐quality Sb shallow‐doped ZnO wave‐guided microcavities have excellent optical responses and a strong light‐field regulation capability, which would greatly promote the development of ZnO cavity‐based photoelectronic devices. [ABSTRACT FROM AUTHOR]

We demonstrate an easy, novel synthesis of nanosheet-based flower-like ZnO microspheres without any catalyst and template. The layered hydroxide zinc acetate Zn5(OH)8(CH3COO)2·2H2O (LHZA) nanostructures, one of important and efficient precursors to synthesize three dimensional (3D) ZnO hierarchical microstructures, are first fabricated in aqueous solution at room temperature. The detailed crystal structure and formation mechanism of the LHZA are also investigated. It is noteworthy that the initial ZnO seed layer is crucial to the growth of the final nano/microarchitectures. We found that the as-synthesized hierarchical ZnO microspheres obtained from the decomposition of LHZA showed excellent photocatalytic activity for the photodegradation of rhodamine 6G. This facile, efficient, and economical work provides a new route to simply and mildly synthesize ZnO 3D hierarchical microspheres, which may be adopted to prepare other metal oxide microstructures. [ABSTRACT FROM AUTHOR]

Highlights: [•] (Liquid+liquid) equilibrium for quaternary system was measured. [•] The components include benzene, cyclohexane, N,N-dimethylformamide, sodium thiocyanate. [•] The (liquid+liquid) equilibrium data can be well correlated by the NRTL model. [•] Separation of benzene and cyclohexane by NaSCN+DMF was discussed. [ABSTRACT FROM AUTHOR]

Abstract: Nanosheet-based three-dimensional (3D) hierarchical rosette-like In2O3 microspheres and hollow microspheres are successfully prepared by a hydrothermal and subsequent annealing process. The formation mechanism of In(OH)3(En)2 microsphere precursors is investigated systematically, and the possible chemical reactions at each stage are proposed. The complexing agent and the surfactant are the two important factors to control the morphologies and microstructures of the final products. The as-synthesized hierarchical In2O3 microspheres show excellent sensing response to volatile organic compounds such as acetone and toluene gases. The detection limit can be as low as ∼500ppb level in atmosphere. In addition, the sensing mechanism based on the change of surface resistance is discussed. Such novel In2O3 microspheres may be a promising candidate for sensor application in detecting acetone or toluene in different environments. [Copyright &y& Elsevier]

Abstract: Sodium carboxymethyl cellulose (CMC) have been used to disperse carbon nanotubes (CNTs) and have potential applications to make the CNTs/epoxy or CNTs/epoxy/carbon fiber composites. In this paper, the curing kinetics of epoxy resins with and without CMC and cured with 4,4′-diamino diphenyl methane (DDM) hardener was studied by non-isothermal differential scanning calorimetry (DSC). A two-parameter (m, n) autocatalytic model was used to describe the cure kinetics of the epoxy resins. The kinetic parameters were calculated with the Málek method and least square regression (LSR) method, respectively. The curves by Málek method and LSR method both show a good agreement with the experimental data for Epoxy/DDM and CMC/epoxy/DDM systems. The results, based on the two methods, showed that the activation energy was no obvious difference with the addition of CMC, which indicated that the CMC have no effect on the curing reaction without changing the kinetic model. [Copyright &y& Elsevier]

We demonstrate a novel way to realize room-temperature polariton parametric scattering in a one-dimensional ZnO microcavity. The polariton parametric scattering is driven by a polariton condensate, with a balanced polariton pair generated at the adjacent polariton mode. This parametric scattering is experimentally investigated by the angle-resolved photoluminescence spectroscopy technique under different pump powers and it is well described by the rate equation of interacting bosons. The direct relation between the intensity of the scattered polariton signal and that of the polariton reservoir is acquired under nonresonant excitation, exhibiting the explicit nonlinear characteristic of this room-temperature polariton parametric process. [ABSTRACT FROM AUTHOR]

Abstract: Uniform single-crystalline In(OH)3 hollow microcubes have been synthesized in large quantities via a hydrothermal reaction of InCl3 with NaF and ethylene glycol (EG) at 140–220°C for 12h. Porous In2O3 hollow microcubes with a polycrystalline cubic structure can be obtained via calcining In(OH)3 precursors at 400°C for 2h in air. Controlled Synthesis of In(OH)3 and In2O3 hollow microcubes with the average edge lengths in the range of 2.0–4.7μm can be achieved by changing the hydrothermal reaction temperature. The In(OH)3 hollow microcubes were formed via an EG-assisted oriented attachment growth route using HF bubbles as the templates. Photocatalytic activities of the as-synthesized porous In2O3 hollow microcubes were studied at room temperature. The results indicated that the hollow In2O3 nanostructures display high photocatalytic activity in the photodegradation of rhodamine B and methyl orange. [Copyright &y& Elsevier]

Abstract: Porous Ni3Al intermetallic material with a mean pore diameter of around 1μm was prepared by step sintering Ni and Al powder pressed compacts in vacuum furnace at 900°C. The electrocatalytic activity of the as-fabricated porous Ni3Al material as an electrode for hydrogen evolution reaction (HER) in alkaline solutions was investigated by cyclic voltammetry (CV), linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) techniques. It is found that the onset potential of porous Ni3Al for HER shifted in the positive direction favoring hydrogen generation with lower overpotential, compared with foam Ni and dense Ni electrodes. Effects of electrolyte concentration and temperature on HER as well as the electrochemical stability in alkaline solution were investigated and the electrochemical activation energy was determined for the porous Ni3Al. The increased activity for HER was attributed to the high porosity, an increased electrochemical surface area and the nanostructure of porous Ni3Al electrode. The corrosion tests showed that the corrosion resistance of porous Ni3Al electrode changed during the immersion process due to the formation of passive film layers. [Copyright &y& Elsevier]

Experimental liquid−liquid equilibrium (LLE) data were measured for benzene cyclohexane N,N-dimethylformamide (DMF) ammonium thiocyanate (NH4SCN) at atmospheric pressure and 298.15 K. The experimental data were correlated using the Othmer−Tobias correlation. The selectivity coefficients of DMF NH4SCN for benzene are 2 to 15 in this work. The results revealed that the selectivity coefficients increased with the decreasing of the concentration of benzene in the raffinate and increased with the increasing of the mass fraction of NH4SCN in the DMF NH4SCN mixture. Considering the high selectivity for benzene, DMF NH4SCN may be used as a potential extracting solvent for the separation of benzene and cyclohexane. [ABSTRACT FROM AUTHOR]

Abstract: LaPO4, LaPO4:Ce3+ and LaPO4:Ce3+, Tb3+ particles with different morphologies and sizes have been successfully synthesized via a simple EDTA assisted hydrothermal method. The effects of the doping components, pH value, and the chelating reagent on the phases, structures and morphologies were well investigated by means of X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Photoluminescent (PL) spectra and kinetic decays were used to characterize the fluorescent properties of the samples. The results reveal that all the samples are of high purity and assigned to the single-crystalline monoclinic structure of LaPO4 phase. The aspects ratio of the nanostructures synthesized in acid synthetic condition is larger than those obtained in alkaline solution. Additionally, the Ce3+ or/and Tb3+ doped LaPO4 particles show less smoother surface compared with pure LaPO4. Furthermore, the tendency for anisotropic growth under hydrothermal conditions can be simply enhanced by selecting the chelating ligands (EDTA). The possible growth mechanism of the LaPO4:Ln3+ (Ln = Ce3+, Tb3+) nanostructures has been proposed as well. Upon ultraviolet excitation, LaPO4:Ce3+ and LaPO4:Ce3+, Tb3+ phosphors show the characteristic 5d–4f emissions of Ce3+ and 5D4–7F j (j = 6–3) emission lines of Tb3+, respectively. [ABSTRACT FROM AUTHOR]

The design of hierarchical nanostructures with a controlled composition arrangement is a promising strategy to achieve high ion transport and enhanced charge storage for high-performance supercapacitor electrode development. Herein, we report a high-energy-density electrode based on CoP/Mo-NiCoP nanoplates array on carbon cloth templated by the metal-organic frameworks (MOFs). The unique hierarchical 3D structure provides an extremely large surface that enables excellent accessibility to the active surface sites, promoting electrochemical energy storage performance effectively. In addition, according to the density functional theory (DFT) calculation, Mo-doped in CoP/NiCoP nanoplates results in a desired electronic structure to enhance electronic transfer capability. As a result, the CoP/Mo-NiCoP electrode presents a high specific capacity of 892.6 C g−1 (248 mAh g−1) at the current density of 1 A g−1, as well as good rate capability (78.9% of capacity at 20 A g−1), and long-term cycling stability (82.6% retention after 10000 cycles at 4 A g−1). Furthermore, the assembled supercapacitor yielded a high energy density of 64.7 Wh kg−1 at 800 W kg−1 with an operating voltage of 1.6 V, outperforming most asymmetric supercapacitors. This work shows a promising hierarchical nanomaterial array for the development of high-performance flexible supercapacitors. [ABSTRACT FROM AUTHOR]

Abstract: In2O3 nanowires have been synthesized on a large-area surface by direct thermal oxidation of indium grains coated with an Au film at 700–850°C under the flow of O2. The indium grains were used as both a reagent and a substrate for the growth of In2O3 nanowires. The as-synthesized In2O3 nanowires were characterized by transmission electron microscopy, scanning electron microscopy and Raman spectrum. It was found that the In2O3 nanowires were a polycrystalline with the body centered cubic structure and had a controllable diameter in the range of 60–250nm with lengths of up to 10μm by varying the heating temperature. A possible mechanism was also proposed to account for the growth of these In2O3 nanowires. [Copyright &y& Elsevier]

The exploration of cooperative states in many‐body systems is a key research area. It focuses on superfluorescence (SF), a phenomenon linked with radiative dipole coupling, and its intersection with classical lasing effects. This produces a unique lasing‐field‐hybrid cooperative dipole (LCD) state through optical cavity‐enhanced superfluorescence (CESF). A coherent energy transfer is demonstrated between two such states within a perovskite quantum dot (QD) superlattice. This results in competitive luminescence timing dynamics. The findings reveal that stimulated energy transfer occurs when two cooperative cavity‐exciton states coexist, controllable via a dual‐pulse pump technique. This understanding is vital for advancing quantum phenomena knowledge and enhancing optoelectronic devices. [ABSTRACT FROM AUTHOR]

Lead halide perovskite quantum dots (LHP QDs) emerge as versatile photonic sources in electroluminescence and laser devices. Their applications in optoelectronic devices are hindered by surface distortion and ligand stripping during the purification process. In addition, the device performance roll‐off suffers from the ultrafast non‐radiative Auger recombination (AR). To address these issues, herein, CsPbBr3 QDs are prepared with sizes ranging from 6.5 to 9.2 nm and the universal surface repairing strategy is proved to efficiently increase the biexciton lifetime and quantum yield up to 1.4 and 3 times, respectively. The strategy provides a PbBrx rich surface and strong binding didodecyldimethylammonium bromide (DDAB) ligands to achieve near‐unity photoluminescence efficiency, which significantly improves their stability against anti‐solvents and aging in ambient conditions. A single‐mode laser device is realized by self‐assembling the QDs into superlattice as optical microcavity, with low threshold of 9.45 µJ cm−2, quality factor of 2187 and ultrafast lifetime of 3.22 ps. The superlattice laser is demonstrated as an optical encoder with large coding bandwidth of 0.133 THz. This work proposes new insight into the non‐radiative AR process in these single‐component CsPbBr3 QDs, and will pave the way for optoelectronic devices working in intense conditions. [ABSTRACT FROM AUTHOR]

High-quality In2O3 polyhedrons with different morphologies were fabricated and studied as vertical Fabry-Pérot (FP) microcavities. By using the microphotoluminescence technique, we identified a series of FP resonant modes in such systems, whose energies lie in the visible spectral range and are scalable with the cavity size. Experimental results are in good agreement with full-wave numerical simulations and can be well fitted with a plane wave interference model. Compared with the conventional one dimensional nanowire/nanobelt FP cavities, such vertical FP microcavities have much less optical loss and provide efficient optical modulations, which may find many applications in developing optical devices. [ABSTRACT FROM AUTHOR]

Nearly perfect In2O3 octahedra were fabricated and studied as optical resonators. Electron microscopy images revealed that the octahedra have single-crystal structures, very smooth surfaces, and regular geometric morphologies. Bow-tielike modes in the visible spectral range were clearly observed at room temperature by using the spatially resolved spectroscopic technique. The experimental observations are described and fitted well with the plane wave interference model and Cauchy dispersion formula for refractive indices. [ABSTRACT FROM AUTHOR]

We report on the use of In2O3 nanowires with hexagonal cross section as optical whispering gallery resonators. The single-crystal In2O3 nanowires were fabricated by an in situ thermal oxidation method. Whispering gallery modes (WGMs) in the visible spectral range were directly observed at room temperature. Due to the slight tapering of the nanowires, the energies and orders of the WGMs were modulated when excitations were scanned along the c-axis (length) of the nanowires. The experimental results were explained and fitted well with a plane wave interference model and Cauchy dispersion formula for refractive indices. [ABSTRACT FROM AUTHOR]

Electrode materials with a large internal surface area, tunable pore size, efficient transport of electrons and high ion-accessibility are highly desired in the development of advanced flexible supercapacitors. Recently, transition metal sulfides with rationally designed nanostructures have attracted considerable attention as electrode materials for supercapacitors. In this study, we report the synthesis of Zn 0.76 Co 0.24 S/NiCo 2 S 4 nanosheets grown on carbon cloth using a two-dimensional bimetallic Zn/Co zeolitic imidazolate framework (named as Zn/Co-ZIF-L) as a precursor through a simple and cost-effective chemical solution process. The ZIF-derived Zn 0.76 Co 0.24 S/NiCo 2 S 4 electrode nanosheets deliver an ultrahigh specific capacitance of 2674 F g−1 at 1 A g−1, a superior ratio performance and cycle stability. Furthermore, the as-fabricated Zn 0.76 Co 0.24 S/NiCo 2 S 4 //AC all-solid-state asymmetric supercapacitor (ASC) achieves a maximum energy density of 48.1 Wh kg−1 as well as a power density of 837 W kg−1, and a superior cycling performance of 91% retention after 5000 cycles. The detailed electrochemical kinetic analysis demonstrates that the total capacitance of Zn 0.76 Co 0.24 S/NiCo 2 S 4 is derived from its capacitive-effective charge storage mechanism. This ZIF-derived strategy provides a reasonable and simple way to synthesize transition metal sulfides as potential active materials for next-generation flexible supercapacitors. Image 1 • Zn/Co-based MOFs derived Zn 0.76 Co 0.24 S/NiCo 2 S 4 nanosheets were prepared successfully. • The Zn 0.76 Co 0.24 S/NiCo 2 S 4 electrode exhibited remarkable specific capacitance. • A flexible all-solid-state Zn 0.76 Co 0.24 S/NiCo 2 S 4 //AC ASC device was fabricated. • The enhanced property is due to the nanostructure, porosity and conductivity. [ABSTRACT FROM AUTHOR]

Micro/nano photonic barcoding has emerged as a promising technology for information security and anti-counterfeiting applications owing to its high security and robust tamper resistance. However, the practical application of conventional micro/nano photonic barcodes is constrained by limitations in encoding capacity and identification verification (e.g., broad emission bandwidth and the expense of pulsed lasers). Herein, we propose high-capacity photonic barcode labels by leveraging continuous-wave (CW) pumped monolayer tungsten disulfide (WS2) lasing. Large-area, high-quality monolayer WS2 films were grown via a vapor deposition method and coupled with external cavities to construct optically pumped microlasers, thus achieving an excellent CW-pumped lasing with a narrow linewidth (~0.39 nm) and a low threshold (~400 W cm−2) at room temperature. Each pixel within the photonic barcode labels consists of closely packed WS2 microlasers of varying sizes, demonstrating high-density and nonuniform multiple-mode lasing signals that facilitate barcode encoding. Notably, CW operation and narrow-linewidth lasing emission could significantly simplify detection. As proof of concept, a 20-pixel label exhibits a high encoding capacity (2.35 × 10108). This work may promote the advancement of two-dimensional materials micro/nanolasers and offer a promising platform for information encoding and security applications. [ABSTRACT FROM AUTHOR]

Physically unclonable functions (PUFs) have emerged as the most effective method against counterfeiting, leveraging the intrinsic randomness of objects to avoid data replication. However, despite their efficacy, the complexity and high cost of most PUF‐based counterfeiting labels hinder their practical application. Here, a high‐capacity PUF label based on vertically aligned perovskite nanowire (NW) arrays is demonstrated. The NW arrays are conveniently constructed using a low‐cost solution process using an anodized aluminum oxide template. Each pixel within the label is composed of closely packed CsPbBr3 NW arrays of different lengths, resulting in varied lasing signals. The collected signal of each pixel emerged from the lasing output of the NW arrays, generating high‐density and nonuniform multiple‐mode lasing to facilitate information encoding. A quaternary encoding mechanism is used to encode the number of laser modes per pixel. Impressively, it exhibits a mapping resolution of 1600 pixels within 400 µm2, achieving an impressive encoding capacity (1.97 × 10963) and a pixel density (4 bits µm−2) in this compact area. This work shows a promising approach for anticounterfeiting applications because of its simplicity, low cost, and high encoding capacity. [ABSTRACT FROM AUTHOR]

Figures Graph: Figure 1 Schematic of the fabrication of colloidal quantum dot supraparticles through the microemulsion method. Fluorescence Resonance Energy Transfer Properties and Auger Recombination Suppression in Supraparticles Self-Assembled from Colloidal Quantum Dots. Reference 1 Tian X., Chang H., Dong H., Zhang C., Zhang L. Fluorescence Resonance Energy Transfer Properties and Auger Recombination Suppression in Supraparticles Self-Assembled from Colloidal Quantum Dots. [Extracted from the article]

Optically transparent metamaterial absorbers have unexceptionally encountered a great challenge in further improving optical transparency ranging from visible (Vis) to near‐infrared (NIR) and environmental applicability, due to the limitations of constituent materials and multilayer structures. To overcome this limitation, a highly Vis‐NIR transparent metamaterial‐window with outstanding microwave broadband absorption and practical durability is proposed in this paper, which adopts a typical sandwich structure consisting of a cross‐ and cross‐ring‐shaped resonator and a reflective backplane, separated by a quartz glass. Experimental results indicate that the proposed metamaterial‐window achieves >80% absorptivity, covering a wide frequency range of 6.6–13.8 GHz with a relative bandwidth of 70.59%, while the measured shielding effectiveness is >16.94 dB, at 4.0–16.0 GHz. In addition, the corresponding physical mechanism is revealed by exploiting a classical multiple reflections interference model. More significantly, both the patterned resonator and backplane layers are formed by microscale gold meshes with high Vis‐NIR transmittance and environmental resistance, thereby enabling excellent salt spray corrosion resistance and high‐temperature stability, as well as an average optical transmittance of ≈87.35% at 400–1 800 nm. These advantages endow the design a promising candidate for addressing anti‐electromagnetic interference and electromagnetic shielding both in military and civilian. [ABSTRACT FROM AUTHOR]

Metasurface absorbers (meta‐absorbers) are highly compelling in modern optoelectronic devices. However, owing to the limitations of the sandwiched design framework, conventional meta‐absorbers are restricted to fully absorbing only one‐sided incident waves while completely reflecting the electromagnetic (EM) waves from the opposite direction. In addition, the existing absorbers are opaque and their absorption performances are fixed after the initial design. Here, an optically transparent meta‐absorber consisting of bilayer indium tin oxide patterned layers that can achieve bidirectional and broadband absorption in the microwave frequency range is demonstrated. The inherent physics of bidirectional absorption can be attributed to the interference between multiple reflections and transmissions of EM waves. Furthermore, it is demonstrated that the absorption properties of the proposed meta‐absorber can be continuously switched via coherent control by adding another microwave beam to the other side of the meta‐absorber and manipulating the phase difference between the two input waves. The results indicate that the proposed design can enrich the functionalities of few‐layer metasurfaces and break new ground for EM shielding optical windows. [ABSTRACT FROM AUTHOR]

Rubidium lead halides (RbPbX3), an important class of all‐inorganic metal halide perovskites, are attracting increasing attention for photovoltaic applications. However, limited by its lower Goldschmidt tolerance factor t≈0.78, all‐inorganic RbPbBr3 has not been reported. Now, the crystal structure, X‐ray diffraction (XRD) pattern, and band structure of perovskite‐phase RbPbBr3 has now been investigated. Perovskite‐phase RbPbBr3 is unstable at room temperature and transforms to photoluminescence (PL)‐inactive non‐perovskite. The structural evolution and mechanism of the perovskite–non‐perovskite phase transition were clarified in RbPbBr3. Experimentally, perovskite‐phase RbPbBr3 was realized through a dual‐source chemical vapor deposition and annealing process. These perovskite‐phase microspheres showed strong PL emission at about 464 nm. This new perovskite can serve as a gain medium and microcavity to achieve broadband (475–540 nm) single‐mode lasing with a high Q of about 2100. [ABSTRACT FROM AUTHOR]

Rubidium lead halides (RbPbX3), an important class of all‐inorganic metal halide perovskites, are attracting increasing attention for photovoltaic applications. However, limited by its lower Goldschmidt tolerance factor t≈0.78, all‐inorganic RbPbBr3 has not been reported. Now, the crystal structure, X‐ray diffraction (XRD) pattern, and band structure of perovskite‐phase RbPbBr3 has now been investigated. Perovskite‐phase RbPbBr3 is unstable at room temperature and transforms to photoluminescence (PL)‐inactive non‐perovskite. The structural evolution and mechanism of the perovskite–non‐perovskite phase transition were clarified in RbPbBr3. Experimentally, perovskite‐phase RbPbBr3 was realized through a dual‐source chemical vapor deposition and annealing process. These perovskite‐phase microspheres showed strong PL emission at about 464 nm. This new perovskite can serve as a gain medium and microcavity to achieve broadband (475–540 nm) single‐mode lasing with a high Q of about 2100. [ABSTRACT FROM AUTHOR]

Rubidium lead halides (RbPbX3), an important class of all‐inorganic metal halide perovskites, are attracting increasing attention for photovoltaic applications. However, limited by its lower Goldschmidt tolerance factor t≈0.78, all‐inorganic RbPbBr3 has not been reported. Now, the crystal structure, X‐ray diffraction (XRD) pattern, and band structure of perovskite‐phase RbPbBr3 has now been investigated. Perovskite‐phase RbPbBr3 is unstable at room temperature and transforms to photoluminescence (PL)‐inactive non‐perovskite. The structural evolution and mechanism of the perovskite–non‐perovskite phase transition were clarified in RbPbBr3. Experimentally, perovskite‐phase RbPbBr3 was realized through a dual‐source chemical vapor deposition and annealing process. These perovskite‐phase microspheres showed strong PL emission at about 464 nm. This new perovskite can serve as a gain medium and microcavity to achieve broadband (475–540 nm) single‐mode lasing with a high Q of about 2100. [ABSTRACT FROM AUTHOR]

To accelerate the design of metamaterial microwave absorbers (MMAs), in this work, we developed a deep neural network model to predict the spectrum based on the known structural parameters at the beginning. Then, a tandem network was constructed, which can predict the geometries of an unknown MMA based on a desired absorption characteristics with a small mean square errors of validation set (8.3 × 10−4). With the help of the tandem network, a dual band absorber that achieves an absorption rate greater than 85% in the range of 5.1–14 GHz was obtained. By comparing with traditional methods, the demonstrated methodology can greatly accelerate the whole process and realize an inverse design. [ABSTRACT FROM AUTHOR]

Optical coding is widely applied in communication and data processing fields due to its practical and powerful characteristics, such as high transmission rate and operational convenience. However, improvements in the loading information capacity of optical encoders always result in increased energy consumption. It is a challenge to realize an optical encoder that combines energy savings, high bandwidth, and miniaturization. Here, both the concept and the demonstration of a perovskite sub‐micro‐encoder with an 84% energy‐saving efficiency and a tunable bandwidth of up to 200 GHz are reported. The way to code the radiative dynamics of the light source allows for the reduction of unnecessary energy consumption from the initial stage through the control of the radiation core. Moreover, the miniature encoder generates code sequences of good coherence, stimulating the development of perovskite‐based optical microchips for ultrafast information processing. [ABSTRACT FROM AUTHOR]

Cavity‐enhanced superfluorescence (CESF) in quantum dot (QD) system is an ultrafast and intense lasing generated by combination of quantum coupling effect and optically stimulated amplification effect, which can provide a new idea for realizing high quality blue light sources and address the limitation of conventional inefficient blue light sources. Modifying halide composition is a straightforward method to achieve blue emission in perovskite QD system. However, the spectral instability introduced by photoinduced halide phase segregation and low coupling efficiency between QDs and optical cavities make it challenging to achieve stable blue CESF in such halide‐doped QD system. Herein, long‐range‐ordered, densely packed CsPbBr2Cl QD‐assembled superlattice microcavities in which the two core issues can be appropriately addressed are developed. The QD superlattice structure facilitates excitonic delocalization to decrease exciton‐phonon coupling, thus alleviating photoinduced phase segregation. By combination of theoretical analysis and temperature‐dependent photoluminescence (PL) measurements, the underlying photoinduced phase segregation mitigation mechanism in mixed halide superlattices is clarified. Based on the CsPbBr2Cl QD superlattices with regularly geometrical structures, in which the gain medium can be strongly coupled to the naturally formed microcavity, stable and ultrafast (3 ps) blue CESF with excellent optical performance (threshold ≈33 µJ cm−2, quality factor ≈1900) is realized. [ABSTRACT FROM AUTHOR]

Integrating broadband absorption, dynamic tunability, and high optical transparency into a single microwave absorber remains a crucial challenge. Here, an ultra‐broadband, tunable, and transparent microwave meta‐absorber comprising double‐layer indium tin oxide resonant patterns and a water‐based substrate is theoretically presented and experimentally demonstrated. Experimental measurements indicate that the designed meta‐absorber can achieve over 90% absorption in an ultra‐broadband frequency range of 12.49–98.21 GHz with a relative bandwidth of 154.9%, while the average optical transmittance is 60.49%. In addition, a multiple reflections interference model is employed to elucidate the physical mechanisms of the ultra‐broadband absorber. Furthermore, its absorption performance can be reversibly switched between ultra‐broadband and dual‐broadband by altering the water substrate thickness. These peculiar properties make the proposed meta‐absorber more favorable for practical applications in modern stealth materials and optical windows. [ABSTRACT FROM AUTHOR]

Surface molecularly imprinting polymer (SMIP) was utilized in the removal of a residual pesticide (carbaryl (CBL)) in water and simulated fruit juice. Being the crosslinking agent, ethylene glycol dimethacrylate (EGDMA) was copolymerized with the monomer, methacrylic acid (MAA) and CBL as the template molecules on the surface of the silica gel particles to produce the SMIP adsorbents. The SMIP adsorbents showed good selectivity and good adsorption capacity for CBL in the competitive adsorptions with two structurally related carbamate pesticides. The effect of the pretreatment solvents on the adsorption capacity of the SMIP adsorbent was investigated with the results of the numerical simulations. The adsorption isotherms and the adsorption kinetics were well described by the Freundlich equilibrium model and the pseudo-second-order kinetic model, respectively. Scatchard plot analysis revealed that there were two classes of binding sites populated in the SMIP adsorbents. In addition, the good selective adsorption of CBL by the SMIP adsorbent in a simulated fruit juice containing vitamin C and fructose indicated the great potential of the SMIP adsorbents to remove residual pesticide in food industry and processing industry for agricultural products. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract The understanding of the structure-function relationship of the oxygen-evolving center (OEC), a Mn 4 Ca-cluster, in photosystem II is impeded mainly due to the complexity of the protein environment and lack of rational chemical models as a reference. In this study, two novel Mn 4 -oxido complexes have been synthesized and characterized, in which the peripheral ligands of the [MnIII 4 ] core are provided by eight μ 2 -carboxylate groups and two neutral terminal ligands (pyridine or isoquinoline). This type of peripheral ligation is very similar to the Mn 4 Ca-oxide model complexes recently reported to mimic the OEC. The new Mn 4 -oxide complex can catalyze the oxygen-evolving reaction in the presence of ButOOH as an oxidant. The structure and redox properties comparison of the Mn 4 -oxido and Mn 4 Ca-oxido complexes provide important clues to understanding the functional role of Ca in the OEC in natural photosynthesis, and develop more efficient artificial catalysts for the water-splitting reaction in the future. [ABSTRACT FROM AUTHOR]

Ultrafast saturable absorption (SA) materials that are capable of blocking the optical absorption under strong excitation have extensive applications in photonic devices. This work presents core/shell colloidal quantum dots (CQDs) which have the quantized energy levels, excellent band gap tunability, and possess significant SA performance. When the band gap is close to the pump pulse energy, the CQDs show significant resonant SA response. At the same excitation conditions, the core/shell CQDs dispersions show better SA response than graphene dispersions, and comparable to the recently reported molybdenum disulfide. The carrier dynamics of the SA of the CQDs is analyzed systematically. The research has also found that the two-photon absorption of the CQDs show nearly cubic power law of the band gap, while the SA performance keeps almost the same in the nonresonant regime. Further, superior passive Q-switched laser behavior is observed using the CQDs as a saturable absorber. The results directly reveal the physical processes of this basic problem and broaden the applications of CQDs in photonic devices. [ABSTRACT FROM AUTHOR]

We present the nonlinear optical properties of CsPb(Br/I)3 perovskite quantum dots (QDs) with high crystallinity. The perovskite QDs show better two-photon absorption response than the traditional metal chalcogenide QDs. And, the photoluminescence peak of the halogen vacancies in perovskite nanocrystals was experimentally observed for the first time. [ABSTRACT FROM AUTHOR]

Single perovskite alloy micro‐nano structure capable of emitting multi‐wavelength tunable lasing is desirable for its potential application in highly integrated photonic devices. However, owing to the soft and dynamic crystal lattice of perovskite and the low mobility energy of halide anion, it is still a challenge to obtain alloy micro‐nano structures with a stable bandgap gradient. Herein, based on the highly ordered superlattice consisting of well‐separated individual quantum dots and precise anion exchange strategy, a single perovskite alloy superlattice is obtained with a widely tunable bandgap. The photoluminescence (PL) spectra results indicate that the stability of the bandgap difference of the alloy superlattice sample is approximately 10 times higher than that of the previously reported perovskite single‐crystal alloy nanowires. By combination of quantitative study based on confocal PL measurements and theoretical calculations, the kinetics and atomic‐scale anion exchange mechanism are analyzed, the latter being responsible for the formation of stable bandgap gradient in the alloy superlattice. Multi‐wavelength lasing is further realized in single alloy superlattice. In addition, carrier transportation dynamics reveals the energy‐transfer process in the alloy superlattice, explaining the difficulties of realizing multicolor lasing. The work provides a new approach to solving problems in the field of stable multicolor microlasers. [ABSTRACT FROM AUTHOR]

We demonstrate the observation of the strong excitons-photons coupling in pencil-like ZnO microwires at room temperature. The pencil-like ZnO microwires with high optical quality were fabricated by using a carbothermal growth method at 1100 °C. The strong coupling of excitons and photons is evidenced by using angle-resolved photoluminescence spectroscopy. By scanning excitations spot from the arm to the tip of the pencil-like ZnO microwires, we found that the confinement of the tip is weaker than that of the arm due to the shrinked size. With increasing the excitation power, the lowest energy states of exciton-polariton modes are remarkably populated, and lasing phenomena are observed. By using the coupled oscillator model, the polariton effect can be well described. [ABSTRACT FROM AUTHOR]

(Liquid + liquid) equilibrium (LLE) data were measured experimentally at T = (298.15 or 303.15) K and atmospheric pressure for the (benzene + cyclohexane + dimethyl sulfone (DMSO)) system. The Othmer–Tobias equation was applied to verify the reliability of the data. Based on the data, the selectivity of DMSO was estimated and compared with that of ionic liquids. The highest selectivity coefficient of DMSO can reach beyond 14, which means it is able to compete with some ionic liquids and it would be a good extractant to separate benzene from cyclohexane. At the same time, the NRTL model was used to correlate the data and the results show that the model agrees on the experimental data very well. [ABSTRACT FROM AUTHOR]

[Display omitted] • The proposed device constitutes an infrared tri-band perfect absorber. • Absorption peaks can be independently tuned by varying the carrier density of MoS 2. • Multilayered interference model is proposed to elucidate the absorption mechanism. • The absorber is rather insensitive to light polarization and angle of incidence. In this paper, we present an independently tunable infrared tri-band perfect absorber, which consists of double-layer stacked molybdenum disulfide (MoS 2) metasurfaces and a gold mirror separated by insulating layers. The light absorption in monolayer MoS 2 is strongly enhanced, and three absorption peaks of over 99.5% are achieved. We demonstrate that the three absorption peaks can be independently tuned by changing the carrier density of the corresponding MoS 2 layer, indicating no interlayer coupling between the top and bottom MoS 2 layers. Based on this, we propose a multilayered multiple interference model to elucidate the independently tunable perfect absorption mechanism. The theoretically calculated absorption spectrum agrees excellently with the simulated spectrum. In addition, the tri-band perfect absorber possesses polarization-independent and incident-angle-insensitive properties. The proposed metasurfaces may help in designing multilayered metasurface absorbers and thus the fabrication of MoS 2 -based optoelectronic devices such as modulators, tunable sensors, thermal emitters, and photodetectors for infrared waves. [ABSTRACT FROM AUTHOR]

Cavity‐enhanced superfluorescence is an ultrafast and intense lasing produced by strong interaction between superfluorescence and optical cavity. However, due to the quite difficulty of particle cooperative emission in solid‐state systems, and the low coupling efficiency between superfluorescence and optical cavity, research on ultrafast optical properties of cavity‐enhanced superfluorescence is thus far in its infancy. Fortunately, perovskites being made into quantum dot superlattice microcavity is an excellent candidate as such light source. This work reveals the time‐dependent redshift process of cavity‐enhanced superfluorescence under high‐power injection, and interprets the physical mechanism of lasing broadening with increasing power from the dynamic perspective. At the same time, the multi‐mode lasing dynamic photoluminescence image output at different times is also tracked. The short‐wavelength resonance mode has a lower stimulated threshold, but its radiation lags behind the long‐wavelength resonance mode by 4 ps in high excited density. These ultrafast optical property researches may promote the application of quantum dot superlattices in information technology, optical communications, ultrafast lasers, and other fields. [ABSTRACT FROM AUTHOR]

Metamaterial absorbers (MMAs) offer a novel and flexible method to realize perfect absorption in specific frequencies, especially in the THz range. Despite the exotic abilities to manipulate light, most previously reported MMAs still suffer from limited bandwidth and tunability. Here we present a thermally switchable terahertz (THz) metasurface that exhibits ultra-broadband absorption and high-transmission characteristics at different ambient temperatures. Our simulations demonstrate that at room temperature the structure is highly transparent. When the ambient temperature reaches 358 K, the proposed design exhibits an ultra-broadband absorption from 0.398 to 1.356 THz with the absorptivity maintaining above 90% and the relative absorption bandwidth reaches up to 109.2%. The structure is demonstrated to be insensitive to the incident angle. Moreover, the bandwidth of such a structure can easily be expanded or reduced by cascading or removing the rings, providing high scalability in practical applications. Such a thermally switchable THz metasurface may have potential applications in various fields, such as optical switching, THz imaging, modulating and filtering. [ABSTRACT FROM AUTHOR]

Multi-band metasurface filters are becoming increasingly pivotal in high-capacity communication technologies. Traditional methods for designing metasurface structures, to date, have relied on empirical approaches to obtain target electromagnetic responses, thereby suffering from low efficiency. Here, we demonstrate an advanced approach for the inverse design of a multi-band metasurface filter, which consists of a multi-objective genetic algorithm (MOGA) in tandem with equivalent circuit model (ECM) analysis. This integration converts specific frequency response requirements into ECM parameter constraints, significantly streamlining the metasurface design and optimization process and offering superior solutions. Using this inverse design method, we theoretically propose a dual-bandpass metasurface filter which can exhibit transmission passbands in any two adjacent frequency ranges among the X-, Ku-, and K-bands. Further, numerical simulations validate the performances of the proposed device, which show great agreement with MOGA-based predictions. Our results pave the way to the effective inverse design of multi-passband metasurface filters which are useful in many applications, such as microwave filters, radar and satellite communication systems, and radio frequency identification devices. • A novel methodology combining MOGA and ECM is proposed for the inverse design of dual-bandpass metasurface filters. • The expected operating frequency of the proposed metasurface filter is switchable within the X-, Ku-, and K-bands. • The device is insensitive to the polarization and incident angle. [ABSTRACT FROM AUTHOR]

Multifunctional wound dressings are promising medical materials for various applications. Among them, dressings with antimicrobial activity, high biosafety, and real-time monitoring have attracted considerable research interest. Herein, a biodegradable hemostatic sponge comprising a chitosan skeleton and polyelectrolyte–surfactant complex (CS–PEC) was developed as a versatile wound dressing for wound pH monitoring and inhibition of bacterial infection. CS–PEC sponge with high porosity exhibited satisfactory fluid absorption capacity and biocompatibility, along with antibacterial properties against E. coli and S. aureus. In vivo experiments in rat liver trauma model revealed that wounds treated with the CS–PEC sponge recorded less blood loss (97.1 mg) and shorter hemostasis time (27.2 s) than those treated with commercial gelatin sponge (309.1 mg and 163.5 s, respectively). Furthermore, PECs based on unconventional luminescent molecules (L -C 16 -Hyp) were used as pH fluorescent indicators, which endowed the sponge with fluorescence-responsive behavior to wound pH changes in the range of 5.0–8.5. Visual images can be captured using a smartphone and converted to RGB color mode values for on-site assessment of wound status. This study sheds light on the design and application of unconventional luminescent materials in wound dressing and provides a smart and effective solution for wound management. [ABSTRACT FROM AUTHOR]

The purpose of this research was to design and synthesize an adsorbent based on polyimide covalent organic frameworks (PICOFs) for uranium-containing wastewater treatment and uranium recovery. A modified solvothermal method was innovatively proposed to synthesize PICOFs with high specific surface area (1998.5 m2 g−1) and regular pore structure. Additionally, a convenient functionalization strategy of PICOFs was designed through polydopamine (PDA) and a well-dispersed polymer (MPC-co-AO) containing multiple functional groups, forming stable composite (PMCA-TPPICOFs) in which the hydrogen bonding and cation-π interactions between PDA and MPC-co-AO played a key role. The obtained PMCA-TPPICOFs as an adsorbent exhibited strong selectivity for uranyl ions (maximum adsorption capacity was 538 mg g−1). In simulated wastewater with low uranium concentrations, the removal rate reached 98.3%, and the concentration of treated simulated wastewater met discharge standards. Moreover, PMCA-TPPICOFs was suitable for fixed-bed column adsorption because of its favorable structure. According to the research about adsorption mechanism, the adsorption primarily relied on electrostatic interaction and complexation. In summary, PMCA-TPPICOFs exhibited good potential for uranium-containing wastewater treatment, expanding the application of PICOFs. And the proposed functionalization strategy and modified solvothermal method may promote research in the fields of material functionalization and COFs synthesis. Uranium is a raw material for nuclear energy applications, which is toxic and radioactive. If uranium is discharged with wastewater, it would not only pose a threat to the environmental protection and life safety, but also cause the loss of precious nuclear raw materials. Although adsorption was considered to be an effective way to remove uranium, many of the developed adsorbents were difficult to apply due to the harsh wastewater environment and complex preparation processes. This study reported a novel adsorbent and a new functionalization strategy, which was expected to solve the problem of uranium recovery in wastewater. [Display omitted] • A modified method was proposed to synthesize polyimide covalent organic frameworks (PICOFs). • PICOFs showed high specific surface area (1998.5 m2 g−1) and regular structure. • PICOFs were used innovatively as substrate material of uranium adsorbent. • A new strategy to functionalize PICOFs was designed using dopamine and a copolymer. • The functionalized PICOFs showed good adsorption performance for uranyl ions. [ABSTRACT FROM AUTHOR]

Chiral resolution of binaphthylamine is often a toilful conundrum in the field of analytical chemistry and biomedicine. The work puts forward a selective, sensitive, and miniaturized analytical method based on molecularly imprinted polymers (MIPs) as adsorbent for miniaturized tip solid‐phase extraction (MTSPE) in the separation of binaphthylamine enantiomer. This method combines the advantages of MIPs (high selectivity), MTSPE (low consumption), and high‐performance liquid chromatography (HPLC, high sensitivity). A simple synthesis methodology of MIP (P2) was conducted through bulk polymerization with (S)‐(−)‐1,1′‐binaphthyl‐2,2′‐diamine (S‐DABN) as template together with methacrylic acid monomer, and ethylene glycol dimethacrylate as cross‐linker in proper porogen, realizing a selective recognition and efficient enrichment for S‐DABN. The method exhibited appreciable linearity (0.06–1.00 mg ml−1), low quantification limit (0.056 mg ml−1), good absolute recoveries (45.70%–69.29%), and high precision (relative standard deviations ≤ 3.54%), along with low consumption (0.50 ml sample solution and 25.0 mg adsorbent). Based on the density functional theory, computational simulation was used to make a preliminary prediction for rational design of MIPs and gave a reasonable elaboration involving the potential mechanism of templates interacting with functional monomers. The adsorption kinetics and thermodynamics were investigated to evaluate the recombination process of substrates. In addition, the selectivity of MIPs for S‐DABN was obtained by MIP‐MTSPE coupled with HPLC, which supports the feasibility of this convenient design process. The proposed method was employed for selective extraction of S‐DABN and exhibited promising potential in the application of chiral analysis. [ABSTRACT FROM AUTHOR]

By using aromatic amino acid as the starting material, a novel chiral catalyst support, porous hypercrosslinked amino acid polymer was synthesized, the recyclable asymmetric metal supported by it catalyzed efficient asymmetric reaction with high ee% (up to 99%). [Display omitted] • Synthesis of a new chiral catalyst support, porous hypercrosslinked amino acid (HCP-AA). • A new heterogeneous asymmetric catalyst. • High enantioselectivity of HCP-AA-Rh for asymmetric hydrosilylation of ketones and olefins (ee% up to 99%). • HCP-AA-Rh can be easily recycled and well maintain the catalytic performance after recycle. The application of asymmetric catalysis in industrial processes is limited by the high cost of chiral ligands and the difficulty associated with recovering precious metal catalysts. Here, based on a FeCl 3 -catalyzed Friedel–Crafts alkylation reaction, an aromatic amino acid was crosslinked with 4,4′-bis(chloromethyl)-1,1′-biphenyl to produce a novel porous chiral catalyst support, hypercrosslinked amino acid polymer (HCP-AA). Subsequently, metal catalysts were loaded on HCP-AA through the coordination of the metal ion with amino acid residues to generate heterogeneous asymmetric catalysts, HCP-AA-M. The resulting catalysts were characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The HCP-AA-M samples were employed to catalyze the heterogeneous asymmetric reaction, and they achieved high enantioselectivities (up to 99% ee). Meanwhile, the catalysts could be readily recovered through filtration, and they exhibited good recycling performances. The results suggested that the utilization of inexpensive amino acids as raw materials for producing porous chiral supports for recyclable high-performance asymmetric catalysts is an effective strategy. [ABSTRACT FROM AUTHOR]