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The directed construction of productive adsorbents is essential to avoid damaging human health from the harmful radioactive and toxic U(VI)-containing wastewater. Herein, a sort of Zr-based metal organic framework (MOF) called PCN-222 was synthesized and oxime functionalized based on directed molecular structure design to synthesize an efficient adsorbent with antimicrobial activity, named PCN-222-OM, for recovering U(VI) from wastewater. PCN-222-OM unfolded splendid adsorption capacity (403.4 mg·g−1) at pH = 6.0 because of abundant holey structure and mighty chelation for oxime groups with U(VI) ions. PCN-222-OM also exhibited outstanding selectivity and reusability during the adsorption. The XPS spectra authenticated the -NH and oxime groups which revealed a momentous function. Concurrently, PCN-222-OM also possessed good antimicrobial activity, antibiofouling activity, and environmental safety; adequately decreased detrimental repercussions about bacteria and Halamphora on adsorption capacity; and met non-toxic and non-hazardous requirements for the application. The splendid antimicrobial activity and antibiofouling activity perhaps arose from the Zr6(μ3-O)4(μ3-OH)4(H2O)4(OH)4 clusters and rich functional groups within PCN-222-OM. Originally proposed PCN-222-OM was one potentially propitious material to recover U(VI) in wastewater on account of outstanding adsorption capacity, antimicrobial activity, antibiofouling activity, and environmental safety, meanwhile providing a newfangled conception on the construction of peculiar efficient adsorbent. [ABSTRACT FROM AUTHOR]

In this work, C2 and C6 disubstituted amidoxime functionalized chitosan foam adsorbent (CMNSC-AO foam) were successfully synthesized with the disubstituted carboxylation reaction and diaminomaleonitrile following with an amidoximation reaction, using cheap and readily available chitosan materials in nature. Newly synthesized CMNSC-AO foam demonstrates efficient uranium (U(VI)) adsorption performance, with a maximum capacity of 470.36 mg/g at pH = 6, and the adsorption effect is significantly better than the traditional mono-substituted amidoxime-functionalized foam chitosan adsorbent (CMC-AO foam) (Qe = 354.75 mg/g). The static and dynamic adsorption of U(VI) under different conditions was evaluated, and the influencing factors in the adsorption process were investigated. Among them, the CMNSC-AO foam exhibits excellent selectivity for U(VI) and the removal rate of U(VI) reaches 92.56% (Kd = 62,200) in a 10 mg/L solution of co-existing various metal ions. In addition, CMNSC-AO foam shows antibacterial properties against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) without adding antibacterial agents and antibacterial ions, reducing the adhesion and contamination of bacteria on the foam adsorbent. CMNSC-AO foam is an effective adsorbent for the removal of U(VI) from the environment due to its excellent adsorption and antibacterial properties owing to the presence of a large number of –NH2 and –NOH groups. [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]

In this study, a mixture of polyvinylidene fluoride (PVDF), polyacrylonitrile (PAN), and dimethylformamide (DMF) as solvent were reacted with hydroxylamine hydrochloride to produce polyvinylidene fluoride (PVDF)/amidoximized polyacrylonitrile (AOPAN) spinning solution, and then a novel composite PVDF/AOPAN was fabricated by electrospinning technique. Later the electrospun PVDF/AOPAN nanofibers (NFs) were treated with KOH and pitched in (plunged in) mini-column to be used as an adsorbent material under continuous flow. The structural and morphological characterization of nanofibers membrane was determined using scanning electron microscope equipped with an energy dispersive spectrometer(SEM/EDS), Fourier transform infrared spectrometer (FTIR), and goniometer, the inductively coupled plasma optical emission spectrometer (ICP-OES) analysis was used to evaluate the adsorption capability. The effects of pH and metal ions concentration on the transport properties of PVDF/AOPAN nanofibers were also studied. The Langmuir model fits well with isotherm data for lead and copper and the Redlich–Peterson model for nickel, whereas pseudo-second order was the best to clearly delineate the investigated kinetics. The modified PVDF/AOPAN NFs showed excellent adsorption capability with very fast kinetics reaching the equilibrium in 90 min for lead, copper, and 60 min for nickel. EDS analysis of PVDF/AOPAN after metal adsorption confirmed the attachment of the metals. Obtained results illustrate that converting PAN to AOPAN enhanced the hydrophilicity drastically. The removal rate for lead, copper, and nickel reached 99.5% 99.5% 99.6% under 10 mg L−1 respectively, more interestingly for lead, even the concentration was 100 mg L−1, the removal rate still reached 98.1%. Moreover, the adsorbent displayed an excellent regeneration ability by using 0.5 M HCl. This study showed that PVDF/AOPAN is an effective adsorbent for Pb(II), Cu(II), and Ni(II) removal in trace amount. [ABSTRACT FROM AUTHOR]

Perovskites—compounds with the CaTiO3-type crystal structure—show outstanding performance in photovoltaics and multiparameter optical emitters due to their large oscillator strength, strong solar absorption, and excellent charge-transport properties. However, the ability to realize and control many-body quantum states in perovskites, which would extend their application from classical optoelectronic materials to ultrafast quantum operation, remains an open research topic. Here, we generate a cooperative quantum state of excitons in a quantum dot ensemble based on a lead halide perovskite, and we control the ultrafast radiation of excitonic quantum ensembles by introducing optical microcavites. The stimulated radiation of excitonic quantum ensemble in a superlattice microcavity is demonstrated to not be limited by the classical population-inversion condition, leading to a picosecond radiative duration time to dissipate all of the in-phase dipoles. Such a perovskite-assembly superlattice microcavity with a tunable radiation rate promises potential applications in ultrafast, photoelectric-compatible quantum processors. The realization and control many-body quantum states in perovskites would extend their application to ultrafast quantum operation. Here, the authors generate a cooperative quantum state of excitons in a lead halide perovskite quantum dot ensemble and control the ultrafast radiation through optical microcavites. [ABSTRACT FROM AUTHOR]

This paper reviews recent advances in the nanotube and graphene polymer composites synthesized in our laboratories for laser protection application, i.e., OL. We first discuss the mechanisms involved in the polymer nanocomposites for OL and the Z-scan technique used to measure the nonlinear optical properties of the materials in question. Subsequently, the design, synthesis, characterization, and OL properties of the representative nanotube and graphene polymer composites are introduced, followed by a prospect for use of carbon nanomaterial polymer composites for optical limiting. [ABSTRACT FROM AUTHOR]

β-Ga2O3 cone-like nanowires have been in-situ grown on the surface of gallium grains and films by heating gallium substrates at 750–1000°C for 2 h in air. The controllable synthesis of β-Ga2O3 nanowires with different diameters and lengths was achieved by adjusting the heating temperature and time. The as-synthesized products were characterized by means of X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results showed that the β-Ga2O3 nanowires are single crystalline with a monoclinic structure and have a controllable diameter and length in the range of 30–100 nm and 0.5–1.5 μm, respectively. A possible mechanism was also proposed to account for the formation of β-Ga2O3 cone-like nanowires. Photoluminescence spectra of the β-Ga2O3 nanowires obtained at different temperatures were measured at room temperature, and a strong blue photoluminescence with peaks at 430 and 460 nm and a weak red photoluminescence with peak at 713 nm were observed. The blue light emission intensity decreases with increasing the reaction temperature, however, the red light emission intensity hardly changes. The blue and red light emissions originate from the recombination of an electron on an oxygen vacancy with a hole on a gallium-oxygen vacancy pair and the nitrogen dopants, etc., respectively. [ABSTRACT FROM AUTHOR]

The superfluorescence effect has received extensive attention due to the many-body physics of quantum correlation in dipole gas and the optical applications of ultrafast bright radiation field based on the cooperative quantum state. Here, we demonstrate not only to observe the superfluorescence effect but also to control the cooperative state of the excitons ensemble by externally applying a regulatory dimension of coupling light fields. A new quasi-particle called cooperative exciton-polariton is revealed in a light-matter hybrid structure of a perovskite quantum dot thin film spin-coated on a Distributed Bragg Reflector. Above the nonlinear threshold, polaritonic condensation occurs at a nonzero momentum state on the lower polariton branch owning to the vital role of the synchronized excitons. The phase transition from superfluorescence to polariton condensation exhibits typical signatures of a decrease of the linewidth, an increase of the macroscopic coherence as well as an accelerated radiation decay rate. These findings are promising for opening new potential applications for super-brightness and unconventional coherent light sources and could enable the exploitation of cooperative effects for quantum optics., (© 2024. The Author(s).)