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The effects of isothermal annealing on the self-assembled nanostructures of spinel manganese oxide ZnMnGaO4 were investigated using transmission electron microscopy and x-ray diffraction. The checkerboard nanostructures and zigzag nanostructures (named "Sierra" nanostructures) coexisted owing to the chemical phase separation of Mn3+ and Ga3+ ions by isothermal annealing at 575 °C. It was observed that the checkerboard nanostructures were dominant in short-time annealing and that the volume fraction of the Sierra nanostructures became more prominent as the annealing period increase. The interdiffusion of Mn3+ and Ga3+ is indicated to play an important role in gaining the total energy of the system by the reduction in the local strain caused by the formation of nanostructures. These results provide further insights into the fabrication of distinct types of nanostructures in complex transition-metal compounds. [ABSTRACT FROM AUTHOR]

Circular dichroism (CD) spectra for pseudo-two-dimensional chiral nanomaterials were systematically investigated and analyzed in relation to the rotational symmetry of the nanomaterials. Theoretically, an ideal two-dimensional chiral matter is CD inactive for light incident normal to the plane if it possesses threefold or higher rotational symmetry. If the matter has two- or onefold rotational symmetry, it should exhibit CD activity, and the CD signal measured from the back side of the matter is expected to be inverted from that measured from the front side. For pseudo-two-dimensional chiral gold nanostructures fabricated on glass substrates using electron beam lithography, matter with fourfold rotational symmetry is found to be CD active, even when special care is taken to ensure that the optical environments for the front and back sides of the sample are equivalent. In this case, the CD signal measured from the back side is found to be almost exactly the same as that measured from the front side. It is revealed that the observed chiro-optical behavior arises from three-dimensional chiral characteristics due to differences in the surface shape between the front and back sides of the structures. For matter that is two- or onefold rotationally symmetric, the CD signal measured from the back side is not coincident with that from the front side. For certain wavelength regions, the CD signals measured from the front side and back side are observed to be similar, while at other wavelengths, the inverted component of the CD signals is found to dominate. The observed CD spectral behavior for reciprocal optical measurement configurations is considered to be determined by a balance between the in-plane isotropic and anisotropic components of the chiral permittivity. [ABSTRACT FROM AUTHOR]

The semiconducting behavior of two-dimensional (2D) metal nanostructures has recently attracted much interest for their possible applications in optoelectronics and others. In particular, tuning the bandgap of such nanostructures can open up a new avenue for fabricating functional nano-devices. In the present article, we report the synthesis of 2D metallic Zn nanosheets at room temperature using a ball mill, which is capable of producing large-scale materials in a single run. Initially, nanoplates were formed for ball milling the octahedral-shaped Zn nanoparticles for the time of milling of 6 h. Subsequent ball milling for another 6 h leads these nanoplates to nearly uniform nanosheets. The thickness of these 2D nanostructures was found to decrease with an increase in the time of milling. Visible photoluminescence (PL) emissions centered at ∼3, ∼2.9, and ∼2.75 eV were observed from all the Zn particles showing semiconductor behavior. The origin of such semiconductor behavior was explained based on the radiative transition of electrons from the sp band to the upper states of the 3d band. This argument was confirmed through the studies of photoelectron spectroscopy and the first principle calculations employing density functional theory (DFT). Furthermore, excitation-dependent PL studies indicated that the bandgap of the 2D Zn nanostructures decreased with the increase in the ball milling time. Therefore, a redshift in the bandgap was observed with the increase in the ball milling time. Such changes in the bandgap with the thickness of 2D Zn nanostructures were also verified from the studies of DFT. Thus, the present study demonstrated that the bandgap of 2D metallic Zn nanostructures could be effectively tuned by reducing the thickness. [ABSTRACT FROM AUTHOR]

The present investigation involves the in situ growth of Ag nanostructures (NSs) onto a rough Cu surface, accomplished through a cost-effective and straightforward fabrication process. The inherent characteristics of the Cu surface contribute to a certain degree of a surface-enhanced Raman spectroscopy (SERS) signal. Upon integration with Ag NSs, the Cu surface serves as an exceptionally sensitive and consistently uniform substrate for surface-enhanced Raman spectroscopy. Notably, a singular substrate accommodates the simultaneous detection of four distinct probe molecules. Subsequent SERS analyses of Ag NSs on Cu were executed under varying laser power conditions. Intriguingly, despite the escalation in laser power, no substantial shifts were discerned in the peak positions corresponding to the probe molecules. Consequently, it can be inferred that, for investigations where peak position shifts hold significance, the utilization of a thermally conductive material in fabricating SERS-active substrates could confer notable advantages. [ABSTRACT FROM AUTHOR]

From the perspective of a bond-order-length-strength correlation, we put forward an analytical solution to describe the size, shape, and wall thickness dependency of melting temperature, entropy, and enthalpy for metallic nanostructures. Theoretical reproduction of measurements clarified that (i) when the crystal size reduces, the atomic coordination number lowers, the atomic cohesive energy decreases, and the surface-to-volume ratio increases; (ii) at the same equivalent radius, with the decrease in the number of sides for polyhedral nanoparticles and polygonal nanowires or nanotubes, the melting temperature, entropy, and enthalpy depress; and (iii) the melting temperature, entropy, and enthalpy of nanotubes are always lower than those of nanowires with the same cross-sectional radius. The present formulation is accurate and convenient, which not only shows deeper insight into the physical origins of a melting thermodynamic property response to perturbations but also provides guidance for the design and optimization of electronic nanodevices. [ABSTRACT FROM AUTHOR]

The temperature coefficient of resistivity (θ T) of carbon-based materials is a critical property that directly determines their electrical response upon thermal impulses. It could have metal- (positive) or semiconductor-like (negative) behavior, depending on the combined temperature dependence of electron density and electron scattering. Its distribution in space is very difficult to measure and is rarely studied. Here, for the first time, we report that carbon-based micro/nanoscale structures have a strong non-uniform spatial distribution of θ T. This distribution is probed by measuring the transient electro-thermal response of the material under extremely localized step laser heating and scanning, which magnifies the local θ T effect in the measured transient voltage evolution. For carbon microfibers (CMFs), after electrical current annealing, θ T varies from negative to positive from the sample end to the center with a magnitude change of >130% over <1 mm. This θ T sign change is confirmed by directly testing smaller segments from different regions of an annealed CMF. For micro-thick carbon nanotube bundles, θ T is found to have a relative change of >125% within a length of ∼2 mm, uncovering strong metallic to semiconductive behavior change in space. Our θ T scanning technique can be readily extended to nm-thick samples with μm scanning resolution to explore the distribution of θ T and provide a deep insight into the local electron conduction. [ABSTRACT FROM AUTHOR]

Machine learning (ML) methods are of rapidly growing interest for materials modeling, and yet, the use of ML interatomic potentials for new systems is often more demanding than that of established density-functional theory (DFT) packages. Here, we describe computational methodology to combine the CASTEP first-principles simulation software with the on-the-fly fitting and evaluation of ML interatomic potential models. Our approach is based on regular checking against DFT reference data, which provides a direct measure of the accuracy of the evolving ML model. We discuss the general framework and the specific solutions implemented, and we present an example application to high-temperature molecular-dynamics simulations of carbon nanostructures. The code is freely available for academic research. [ABSTRACT FROM AUTHOR]

The three-dimensional (3D) nanosized compactness of devices is in high demand for the spintronic-device applicability. However, very few self-organized, periodic magnetic 3D nanostructures of transition metal oxides are known. Here, we report the direct microscopic evidence of a self-assembled, square-shaped, periodic array of coherent orthogonal nanoblock-type structure in an epitaxial SrRuO3 (SRO) thin film (∼90 nm thickness) grown on (001) LaAlO3 (LAO) using pulsed-laser deposition technique. The evolution of different growth facets of SRO over the LAO single crystalline substrate with different thickness are observed. The combined effect of substrate-induced strain and misfit is utilized to grow such self-assembled, ordered nanostructure. The spontaneous formation of such ordered ferromagnetic nano-devices can fill the gap of a miniaturized spintronic device for magnetic memory-based applications. [ABSTRACT FROM AUTHOR]

Nanostructured topological insulators (TIs) have the potential to impact a wide array of condensed matter physics topics, ranging from Majorana physics to spintronics. However, the most common TI materials, the B i 2 S e 3 family, are easily damaged during nanofabrication of devices. In this paper, we show that electron beam lithography performed with a 30 or 50 kV accelerating voltage—common for nanopatterning in academic facilities—damages both nonmagnetic TIs and their magnetically doped counterparts at unacceptable levels. We additionally demonstrate that electron beam lithography with a 10 kV accelerating voltage produces minimal damage detectable through low-temperature electronic transport. Although reduced accelerating voltages present challenges in creating fine features, we show that with careful choice of processing parameters, particularly the resist, 100 nm features are reliably achievable. [ABSTRACT FROM AUTHOR]

Low dimensional ZnO-based materials have drawn much attention for the past few decades due to their unique electronic and optical properties and potential applications in optoelectronic devices. In this Tutorial, we will cover the past and the latest developments in ZnO thin films and micro/nanostructures in terms of excitonic and related lasing processes. First, we give a brief overview of structural and band properties of ZnO along with the linear optical and excitonic properties. Second, we introduce a feedback mechanism for lasing in various forms of ZnO, ranging from nanoparticles to nanowires, nanodisks, and thin films. As for the feedback mechanism, detailed descriptions are given to random lasing, Fabry–Pérot lasing, and whispering gallery mode lasing. Third, we discuss possible gain mechanisms, i.e., excitonic gain and electron–hole plasma (EHP) gain, in ZnO. A special interest is also devoted to the Mott carrier density, which is a crucial parameter to distinguish between excitonic and EHP contributions to lasing. Lastly, recent developments on exciton–polariton lasers based on ZnO microcavities are introduced. [ABSTRACT FROM AUTHOR]

Semiconductor nanocrystals with an anisotropic morphology exhibit unique properties, most notably their linear polarization. The colloidal growth of semiconductor nanorods with core dots inside, also referred to as dot-in-rod (DIR) structure, has enabled the synthesis of anisotropic nanocrystals with better stability and controllable fluorescence polarization. In this study, we synthesize CdSe/CdS DIR nanocrystals, in which the position of the CdSe core particle can be controlled by using different ligand compositions during the CdS growth. Varying the core position within the DIR structure, e.g., from the center to the end of the DIR particles, results in a change in the degree of linear polarization. When the core is positioned at the center of the nanorod, the linear polarization turns out to be higher compared with tip-core DIRs. Time-resolved photoluminescence analysis reveals that the center-core DIRs have higher electron–hole interaction than tip-core DIRs because of weak uniaxial strain in center-core DIR that arises from lattice dislocations at the interface to relieve accumulated strain. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Actin filaments play important physiological functions, which have become potential targets of antitumor drugs. Using chemicals to intervene their polymerization‐depolymerization dynamics would generate new strategies for designing antitumor drugs. In this report, an artificial water channel appending acetazolamide moiety, a ligand that can selectively bind to carbonic anhydrase IX, has been prepared. We demonstrated that this conjugate can target colorectal cancer cells overexpressing carbonic anhydrase IX and trigger the depolymerization of actin filaments of the cancer cells by selectively mediating water transmembrane transport. Moreover, the conjugate‐promoted actin depolymerization led to tumor cell apoptosis and its high antitumor activity in vitro and in vivo against colorectal cancer. The method described herein represents a new and general strategy for designing antitumor drugs by using artificial channel‐mediated selective water transport to promote actin depolymerization. [ABSTRACT FROM AUTHOR]

Highly sensitive p -MoS 2 /n-MoO 3 nanocomposite-based chemo-resistive gas sensors are synthesized by varying the reducing agents using hydrothermal synthesis followed by thermal annealing in an Ar environment for NH 3 and NO 2 detection at 50 °C. Structural characterizations confirmed the existence of MoS 2 nanoflakes and MoO 3 nanoplatelets and the appearance of abundant oxygen adsorption sites and sulfur vacancies in the nanocomposites. The MoS 2 :MoO 3 -based sensor (without any reducing agent) showed preferential detection of NH 3 with 52% sensor response for 5 ppm gas concentration having response/recovery times of 28 s/97 s with n-type sensing behavior dominated by MoO 3 charge carriers. On the contrary, NO 2 gas attracts electrons from the MoS 2 surface, exhibiting p-type sensing behavior with a sensor response of 42 % consisting of response/recovery times of 56 s/116 s with 5 ppm concentration at 50 °C. More interestingly, different adsorption sites and conductive channels play a huge role in the MoS 2 :MoO 3 nanocomposite for exhibiting opposite sensing behaviours upon exposure to NH 3 and NO 2 gases. Enhanced sensitivity is dedicated to synergistic effects appearing due to the construction of p-n heterojunction to strengthen carrier transport by enhancing the sensor response. The present work provides a unique methodology for constructing MoS 2 :MoO 3 -based sensors and the effect of reducing agents on various MoS 2 :MoO 3 -based sensors. Moreover, our study recommends the plausible use of the MoS 2 :MoO 3 composite-based heterojunctions to provide a constructive strategy for improving the performance of gas sensors. [ABSTRACT FROM AUTHOR]

The design and fabrication of active and stable nanostructured electrocatalysts for hydrogen production from the electrochemical water splitting is one of the most important strategies for economical hydrogen production and replacement fossil fuels. Using of Ni-based nanostructured alloy electrodes, synthesized via electrodeposition method, due to having a high active surface area, being binder-free, and also the synergistic effect between the alloy elements, can significantly reduce the energy consumption during hydrogen production. Due to the importance of alloy electrodes and the lack of a comprehensive review in this field, in this review article, at first, the advantages and brief mechanism of the electrodeposition method for the synthesis of nanostructured electrodes are given, and then the types of alloy systems and the resulting morphologies are reviewed. Finally, recent developments in the field of alloy systems for hydrogen production are summarized. Moreover, various methods of creating different alloy nanostructures with electrodeposition method are also described in this article. The purpose of this article is to create a deep understanding of the application of alloy nanostructures and to provide a guide for the synthesis of active and stable electrodes for hydrogen production. In addition, using this review paper, one can able to select appropriate alloy system for reaching the best electrocatalytic properties. • Different modes of electrodeposition mechanisms was reviewed. • Electrodeposited metallic nanostructures have favorable electrocatalytic activity. • Various morphologies can be fabricated via electrodeposition process. • Advantages of electrodeposition process over other methods was highlighted. [ABSTRACT FROM AUTHOR]

Over the past few decades, single-element semiconductors have received a great deal of attention due to their unique light-sensitive and heat-sensitive properties, which are of great application and research significance. As one promising material, selenium, being a typical semiconductor, has attracted significant attention from researchers due to its unique properties including high optical conductivity, anisotropic, thermal conductivity, and so on. To promote the application of selenium nanomaterials in various fields, numerous studies over the past few decades have successfully synthesized selenium nanomaterials in various morphologies using a wide range of physical and chemical methods. In this paper, we review and summarise the different methods of synthesis of various morphologies of selenium nanomaterials and discuss the applications of different nanostructures of selenium nanomaterials in optoelectronic devices, chemical sensors, and biomedical applications. Finally, we discuss possible challenges for selenium nanodevices and provide an outlook on the future applications of selenium nanomaterials. [ABSTRACT FROM AUTHOR]

A systematic study of photoelectrochemical properties in terms of carrier transport was conducted for TiO 2 nanostructure films fabricated on Ti foil at different temperatures (130 °C–210 °C) through alkaline hydrothermal technique, along with the morphological, structural, and optical properties. For samples, the morphology transformed from nanosheets to nanowires, the phase converted from bi-phase of brookite and anatase to pure anatase along with the reduction in the amount of oxygen vacancies as temperature increases. Among them, the dark blue bi-phased TiO 2 (brookite and anatase) prepared at 130 °C of hydrothermal treatment (TiO 2 -130) with nanosheets morphology displayed the optimum photoelectrochemical performance with the highest photocurrent density of 265 μA/cm2 at 1 V (vs. Ag/AgCl), largest carrier density of 1.809 × 1019cm−3 and narrowest space charge region of 11.73 nm. Besides, the large reduction in charge transfer resistance and the width of space charge region caused by simulated solar illumination facilitate the charge transport in photoelectrode especially the TiO 2 -130 with the largest reduction, indicating the great influence of illumination on carrier dynamics. Moreover, the external bias caused the reduction of resistance under irradiation, the increase in the resistance in the dark. Importantly, the TiO 2 -210 showed p-type conductivity under illumination inferred from the negative slope of Mott-Schottky plots, which is first observed and further confirm the influence of light on the charge transfer process. [ABSTRACT FROM AUTHOR]

Structural and electrochemical properties of bismuth ferrite nanostructures produced by pulsed laser deposition with various morphologies are reported. The nanostructures are also explored as electrode materials for high-performance supercapacitors. Scanning electron microscopy images revealed that various bismuth ferrite morphologies were produced by varying the background pressure (10−6, 0.01, 0.10, 0.25, 0.50, 1.0, 2.0 and 4.0 Torr) in the deposition chamber and submitting them to a thermal treatment after deposition at 500 ◦C. The as-deposited bismuth ferrite nanostructures range from very compact thin-film (10−6, 0.01, 0.10 Torr), to clustered nanoparticles (0.25, 0.50, 1.0 Torr), to very dispersed arrangement of nanoparticles (2.0 and 4.0 Torr). The electrochemical characteristic of the electrodes was investigated through cyclic voltammetry process. The increase in the specific surface area of the nanostructures as background pressure in the chamber increases does not lead to an increase in interfacial capacitance. This is likely due to the wakening of electrical contact between nanoparticles with increasing porosity of the nanostructures. The thermal treatment increased the contact between nanoparticles, which caused an increase in the interfacial capacitance of the nanostructure deposited under high background pressure in the chamber. [ABSTRACT FROM AUTHOR]

The ability to manipulate the dimensions, areal density, and form of substrate-supported Au and Ag nanoparticles (NPs) is highly desirable for utilizing their plasmonic properties in biosensing, photovoltaics, and nanophotonic applications. The transformation of thin films into the substrate-supported nanostructures by solid-state dewetting (SSD), provides an avenue to manipulate the dimensional aspects of nanostructures simply and cost-effectively on a large scale. However, spontaneous agglomeration of the film produces randomly distributed and non-uniform nanostructures that must be controlled. Here, we have systematically studied the effect of annealing temperature, between 200 °C and 750 °C, on the dewetting morphology evolution of Au, Ag, and Au–Ag bilayer ultrathin films sputter deposited on the c -plane (0001) sapphire substrates. Regardless of the film thickness, Ag films dewet faster than Au films and produce spherical NPs, compared to faceted Au NPs, with broader size distribution. Whereas, by the SSD of Au–Ag bilayer ultrathin films, highly spherical and monodisperse AuAg bimetallic NPs can be fabricated. Furthermore, we have shown the possibility of fabricating the AuAg bimetallic NPs of varying compositions by adjusting the thickness of individual layers, thus enabling us to smoothly tune the spectral location of plasmonic resonance within the visible range. [ABSTRACT FROM AUTHOR]

Circular dichroism (CD) is a significant optical response of chiral plasmonic nanostructures, with extensive applications in chiral sensing, biological detection, and negative refractive index media. In this study, a substantial enhancement of CD signal is achieved by embedding gold nanorod into planar gold L-shaped nanohole arrays. The structural surface charge distribution revealed that electric and magnetic resonance modes are generated under different circularly polarized lights at the same resonance wavelength. The enhanced CD signals originate from stronger magnetic resonance on L-shaped films and embedded nanorod under right circularly polarized light. Moreover, the CD effect of the nanostructure could be controlled by adjusting the relative positioning, aspect ratio of the embedded nanorod, and the period of the array. To further extend the applications of the nanostructure, the relationship between wavelength and refractive index is explored. These results offer novel insights into the design and manipulation of planar chiral materials with substantial CD and also expand the application of chiral structures in refractive index sensors. [ABSTRACT FROM AUTHOR]

Thermoelectric materials have been widely recognized as a simple approach to harness green energy by converting thermal gradients into electrical energy. However, the intricate interplay between electrical conductivity, Seebeck coefficient, and thermal conductivity in thermoelectric materials presents a challenge to improving their efficiency. Traditional experimental methods and calculation methods have troublesome steps and long cycles for predicting new thermoelectric materials. In this work we present materials informatics-based approach, where statistical and machine learning models like correlation matrix, multiple linear regression, principal component analysis and artificial neural network were employed to find the relationship between features and thermoelectric performance. Furthermore, artificial neural network was used to analyze the roles of several compositional and microstructural features along with temperature on electrical conductivity, thermal conductivity, Seebeck coefficient and thermoelectric figure of merit (ZT) for PANI and quasi 0D carbon-based composites. [ABSTRACT FROM AUTHOR]

In this study, we evaluated the effect of four different strategies for bonding a CAD/CAM resin nanoceramic restoration (Lava Ultimate, 3M) to the dentin surface using a universal adhesive (Scotch Bond Universal, 3M) and adhesive resin cement (RelyX Ultimate, 3M) on the shear bond strength (SBS) and failure mode. The strategies comprised: (i) immediate sealing, immediate bonding; (ii) immediate sealing, bonding after 2 weeks with provisional restoration; (iii) immediate sealing with flowable resin composite reinforcement and bonding after 2 weeks with provisional restoration; and (iv) no immediate sealing, and bonding after 2 weeks with provisional restoration. After bonding, all the specimens were thermocycled, shear tests were performed using a universal testing machine, and failure modes were determined using stereomicroscope and scanning electron microscopy. The highest mean SBS was recorded with immediate sealing, immediate bonding strategy. Most adhesive failures with exposed dentinal tubules were noted in specimens exposed to bonding after 2 weeks with no immediate sealing, which was associated with the lowest SBS. Mixed failures predominated in all immediate dentin sealing groups. Immediate sealing with universal adhesives improves SBS, particularly in the single‐visit approach, which has shown significantly better performance, whereas the provisional phase has a negative effect. [ABSTRACT FROM AUTHOR]

In this study, seawater bittern, a by-product of sea salt production containing a concentrated inorganic substance, was used to recover magnesium in the form of nanostructured magnesium hydroxide/oxide. Mg(OH)2/MgO nanostructures from seawater bittern were synthesized by a precipitation method with different addition of PVA surfactants. The aim of this study was to investigate the effects of PVA surfactant on the morpho-structural properties and thermal behavior of MgO nanostructures. Simple control of the morphology and particle size of MgO nanostructures obtained by the addition of PVA was performed during synthesis. XRD structural analysis showed that the synthesized MgO samples have good crystalline nature. The average crystallite size of the samples is 26 nm, 26 nm, 23 nm, 24 nm, 23 nm and 23 nm, respectively, which decreases with increasing PVA content. Based on the average particle size, the optimum addition of poly(vinyl alcohol) is at a mass ratio of 1:1.5, since the smallest particles are obtained and have a uniform distribution. The SEM and TEM observations show an improvement in the agglomeration behavior of MgO nanoparticles by increasing the PVA content. The constituents of the samples were confirmed by XRF and EDS analysis. [ABSTRACT FROM AUTHOR]

In this work, the influence of the aspect ratio of graphene-based nanostructures (GBNs) and content on the mechanical properties of 3 mol% yttria tetragonal zirconia polycrystalline 3Y-TZP matrix composites was analysed. The influence of the dispersion method and sintering parameters on the flexural strength and elastic modulus of the composites was studied, and the fracture surfaces were characterized to determine the fracture mechanisms that occur. The results showed that small amounts of exfoliated graphene nanoplatelets, with reduced lateral size, and few layer graphene, up to 1.0 and 2.5 vol%, respectively, slightly increase the 3Y-TZP flexural strength. This has been attributed to the tortuosity of the crack propagation pathways and strengthening mechanisms. Higher contents cause a decrease in flexural strength and stiffness because of overlapped GBNs, which can promote the crack propagation. The pull-out of GBN was more significant in composites with non-exfoliated graphene nanoplatelets, where no increase on the flexural or biaxial strength was measured. [ABSTRACT FROM AUTHOR]

Objective(s): Basal cell carcinoma (BCC) is the most common form of skin cancer and the most frequently occurring form of all cancers, affecting sun-exposed areas like the face. Surgery is the main treatment, focusing on safe and minimally invasive methods for better outcomes. Technology has enabled the development of artificial skin substitutes for tissue repair. Tissue engineering uses scaffolds to create functional replacements. This project aims to create an alginate-based hydrogel with PEG-coated gold nanoparticles. Materials and Methods: The project extensively explored the modification of alginate hydrogels with PEG-coated gold nanoparticles, involving the synthesis of gold nanoparticles, their integration with the polymer, and the subsequent preparation of the concentrated hybrid hydrogel. Utilizing various physicochemical techniques, such as UV-visible spectroscopy, transmission electron microscopy, dynamic light scattering, zeta potential analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy, the fabrication process was optimized and characterized. Results: The successful synthesis of the hybrid biomaterial was achieved through robust and highly reproducible methods. The MTT assay results offered valuable insights into the biocompatibility and safety of the PEG-coated gold nanoparticle-loaded alginate-based films. The incorporation of PEG-coated gold nanoparticles allowed for potential drug loading on the nanoparticle surface and, consequently, within the hydrogel. Cellular assays were conducted to assess the potential applications of this novel biomaterial. Conclusion: The addition of polyethylene glycol made it possible to load different drugs onto the gold nanoparticles and also within the hydrogel. This makes it a promising choice for potential uses in tissue engineering. [ABSTRACT FROM AUTHOR]

Surface lattice resonances (SLRs) arise from the long-range dipolar interaction in periodic plasmonic metallic nanostructures and exhibit higher quality factors (Q-factors) compared to plasmon resonances supported in isolated metallic nanostructures. In this Letter, we report a significant improvement in the Q-factor of SLR by a factor of three via modulating the efficiency of a long-range dipolar interaction, which can be achieved by varying the thickness or refractive index of the coating layer on the top of the metallic nanostructures. Under the condition of a weak long-range dipolar interaction, we observe a nascent state of SLR located directly at the Rayleigh cutoff wavelength. Due to the absence of an in-plane diffraction mode at shorter wavelengths, the nascent-SLR dip exhibits an asymmetric shape with a high Q-factor. We experimentally monitor the evolution trend at the onset of the SLR and demonstrate a plasmonic resonance reaching an experimental Q-factor exceeding 100 in the ultraviolet region, outperforming other resonance modes in metallic nanostructures. The reported nascent SLR holds promise for boosting the performance of nano-optic devices. [ABSTRACT FROM AUTHOR]

Poly(methacrylamide‐co‐methacrylic acid) P(MAAm‐co‐MAAc) nanogels were synthesized using emulsion polymerization method and characterized in terms of structure, stimuli‐sensitive behavior and nanosize. The effect of monomer, surfactant (sodium dodecyl sulfate) and cross‐linker (N,N′‐methylenebisacrylamide) concentration on the nanosize of the nanogels was investigated. The hydrodynamic size of nanogels was determined by dynamic light scattering (DLS) and it was found to be in the range of 109.8–146.1 nm. Polydispersity index (PDI) values were lower than 0.3 (in the range of 0.145–0.261) confirming the narrow size distribution of the nanogels. Zeta potential measurements indicated that the nanogels exhibited good stability. Stimuli‐sensitive behavior of the nanogels was evaluated using UV‐visible spectroscopy. Characterization of the nanogels was carried out by Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), X‐ray diffraction (XRD) and scanning electron microscopy (SEM). [ABSTRACT FROM AUTHOR]

Vitamin D, an essential micronutrient crucial for skeletal integrity and various non-skeletal physiological functions, exhibits limited bioavailability and stability in vivo. This study is focused on the development of polyethylene glycol (PEG)-grafted phospholipid micellar nanostructures co-encapsulating vitamin D3 and conjugated with alendronic acid, aimed at active bone targeting. Furthermore, these nanostructures are rendered optically traceable in the UV–visible region of the electromagnetic spectrum via the simultaneous encapsulation of vitamin D3 with carbon dots, a newly emerging class of fluorescents, biocompatible nanoparticles characterized by their resistance to photobleaching and environmental friendliness, which hold promise for future in vitro bioimaging studies. A systematic investigation is conducted to optimize experimental parameters for the preparation of micellar nanostructures with an average hydrodynamic diameter below 200 nm, ensuring colloidal stability in physiological media while preserving the optical luminescent properties of the encapsulated carbon dots. Comprehensive chemical-physical characterization of these micellar nanostructures is performed employing optical and morphological techniques. Furthermore, their binding affinity for the principal inorganic constituent of bone tissue is assessed through a binding assay with hydroxyapatite nanoparticles, indicating significant potential for active bone-targeting. These formulated nanostructures hold promise for novel therapeutic interventions to address skeletal-related complications in cancer affected patients in the future. [ABSTRACT FROM AUTHOR]

The influence of different solvents, including aqueous and nonaqueous types, on the physicochemical properties of V2O5 nanostructures was thoroughly investigated. Various characterization techniques, such as XRD, XPS, FTIR, Raman spectroscopy, UV-vis DRS, SEM, TEM, and BET, were employed to analyze the obtained materials. Additionally, the adsorption properties of the synthesized V2O5 nanostructures for methylene blue were examined, and kinetic parameters of adsorption were calculated. The results demonstrate that the morphology of the obtained crystals can be finely controlled by manipulating water concentration in the solution, showcasing its profound impact on both the structural characteristics and adsorption properties of the nanostructures. Furthermore, the structural changes of the resulting V2O5 material induced by solvents show strong impacts on its photocatalytic properties, making it a promising photocatalyst. [ABSTRACT FROM AUTHOR]

This work presents results on laser-induced surface structuring of AlN ceramic and its application in Surface-Enhanced Raman Spectroscopy (SERS). The laser processing is performed by nanosecond pulses in air and vacuum. Depending on the processing conditions, different surface morphology can be obtained. The ablation process is realized by ceramic decomposition as the formation of an aluminium layer is detected. The efficiency of the fabricated structures as active substrates in SERS is estimated by the ability of the detection of ammonium nitrate (NH4NO3). It is conducted for Raman spectrometer systems that operate at wavelengths of 514 and 785 nm where the most common commercial systems work. The obtained structures contribute to enhancement of the Raman signal at both wavelengths, as the efficiency is higher for excitation at 514 nm. The limit of detection (LOD) of ammonium nitrate is estimated to be below the maximum allowed value in drinking water. The analysis of the obtained results was based on the calculations of the near field enhancement at different conditions based on Finite Difference Time Domain simulation and the extinction spectra calculations based on Generalized Mie scattering theory. The structures considered in these simulations were taken from the SEM images of the real samples. The oxidation issue of the ablated surface was studied by X-ray photoelectron spectroscopy. The presented results indicated that laser structuring of AlN ceramics is a way for fabrication of Al structures with specific near-field properties that can be used for the detection of substances with high social impact. [ABSTRACT FROM AUTHOR]

This work describes the optimization of the one-pot synthesis of fine core–shell nanostructures based on nanogold (Au NPs) and silica (SiO2). The obtained core–shell nanomaterials were characterized by Transmission Electron Microscopy (TEM and by the method of spectroscopes such as UV–Vis Spectroscopy and Fourier Transform Infrared Spectroscopy (FT-IR). In addition, the measurement of the zeta potential and size of the obtained particles helped present a full characterization of Au@SiO2 nanostructures. The results show that the influence of reagents acting as reducers, stabilizers, or precursors of the silica shell affects the morphology of the obtained material. By controlling the effect of the added silica precursor, the thickness of the shell can be manipulated, the reducer has an effect on the shape and variety, and then the stabilizer affects their agglomeration. This work provides also a new approach for Au@SiO2 core–shell nanostructure preparation by further modification with dansyl chloride (DNS–Cl). The results show that, by tuning the silica shell thickness, the intensity of the fluorescence spectrum of Au@SiO2–(CH2)3–NH–DNS nanocomposite is about 12 times higher than that of DNS–Cl. [ABSTRACT FROM AUTHOR]

This paper describes the process of producing chemiresistors based on hybrid nanostructures obtained from graphene and conducting polymers. The technology of graphene presumed the following: dispersion and support stabilization based on the chemical vapor deposition technique; transfer of the graphene to the substrate by spin-coating of polymethyl methacrylate; and thermal treatment and electrochemical delamination. For the process at T = 950 °C, a better settlement of the grains was noticed, with the formation of layers predominantly characterized by peaks and not by depressions. The technology for obtaining hybrid nanostructures from graphene and conducting polymers was drop-casting, with solutions of Poly(3-hexylthiophene (P3HT) and Poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-bithiophene] (F8T2). In the case of F8T2, compared to P3HT, a 10 times larger dimension of grain size and about 7 times larger distances between the peak clusters were noticed. To generate chemiresistors from graphene–polymer structures, an ink-jet printer was used, and the metallization was made with commercial copper ink for printed electronics, leading to a structure of a resistor with an active surface of about 1 cm2. Experimental calibration curves were plotted for both sensing structures, for a domain of CH4 of up to 1000 ppm concentration in air. A linearity of the curve for the low concentration of CH4 was noticed for the graphene structure with F8T2, presenting a sensitivity of about 6 times higher compared with the graphene structure with P3HT, which makes the sensing structure of graphene with F8T2 more feasible and reliable for the medical application of irritable bowel syndrome evaluation. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) are extremely important tools to overcome the limitations imposed by therapeutic agents and effectively overcome biological barriers. Smart designed/tuned nanostructures can be extremely effective for cancer treatment. The selection and design of nanostructures and the adjustment of size and surface properties are extremely important, especially for some precision treatments and drug delivery (DD). By designing specific methods, an important era can be opened in the biomedical field for personalized and precise treatment. Here, we focus on advances in the selection and design of nanostructures, as well as on how the structure and shape, size, charge, and surface properties of nanostructures in biological fluids (BFs) can be affected. We discussed the applications of specialized nanostructures in the therapy of head and neck cancer (HNC), which is a difficult and aggressive type of cancer to treat, to give an impetus for novel treatment approaches in this field. We also comprehensively touched on the shortcomings, current trends, and future perspectives when using nanostructures in the treatment of cancer. [ABSTRACT FROM AUTHOR]

Today, humidity sensors have become an integral part of the daily lives. In particular, humidity sensors using an electronic measuring principle have become the standard. Although these sensors have proven to be a stable measurement method, they have some disadvantages, such as their long response time or the danger of using them in explosive environments. This work introduces photonic crystals as an alternative optical measurement approach. The novel technology of ultra‐fast two‐photon polymerisation printing is combined with a thin‐film deposition process, namely iCVD. This allows to print large area high‐precision 3D templates, which are subsequently coated with a humidity responsive hydrogel thin film (p(HEMA) of 20 nm.The limits of 2PP technology are being pushed allowing the production ofs table and periodic large‐area 3D structures. The flexible customization of hydrogels for ambient conditions make them exceptionally promising for a wide range of sensing applications. Additionally, optical methods for measuring humidity seem to be an excellent alternative to overcome the limitations for current state of the art humidity sensors. The optical detection of changes in ambient air humidity is achieved by observing color changes of the printed structure within the visible wavelength range. [ABSTRACT FROM AUTHOR]

This study demonstrates that the magnetic quadrupole (MQ) can make an indispensable contribution to helical dichroism (HD), which is distinct from HD caused by electric quadrupole (EQ). Specifically, the established multipole expansion theory of the light–matter interaction reveals that EQ‐induced HD belongs to the pure electric dipole–quadrupole (E1‐E2) excitation, while newly discovered MQ‐induced HD belongs to the pure magnetic dipole‐quadrupole (M1‐M2) excitation. Metallic propeller meta‐molecules are used to elaborate on this novel physical mechanism and demonstrate that HD can be significantly enhanced and flexibly tuned by increasing stereo twist of propeller meta‐molecules or slightly focusing the linearly polarized vortex beam to improve the orbital angular momentum number. Importantly, the aforementioned intriguing phenomena are validated by fabricating stereo twisted propeller meta‐molecules via nano‐kirigami method. The findings reveal a paradigm‐shift approach to manipulate the chiroptical response of a single metallic nanostructure via photonic orbital angular moment, opening prospects for optical encryption, communication, next‐generation chiroptical spectroscopy, and chiral vortex optical devices. [ABSTRACT FROM AUTHOR]

Nanostructured Y‐TZP samples with Non‐Homogeneous Yttria Distribution (NNHYD) were prepared by mixing co‐precipitated 3Y‐TZP powder (Tosoh TZ‐3Y) with yttria‐free monoclinic powder (Tosoh TZ‐0), yielding an overall yttria content of 2 mol%. The cyclic fatigue behavior of NNHYD was evaluated by Step‐Stress Accelerated Life Testing (SSALT) and mechanical cycling in a biaxial flexural strength test (BFST) setup and compared to Conventional Submicrometric 3Y‐TZP (CS). Physical, structural, microstructural, and mechanical characterizations of all groups were also evaluated and compared before and after artificial aging in autoclave. NNHYD presented a higher capacity for damage accumulation and maintenance of phase transformation potential than CS, associated with elevated resistance to the propagation of Low‐Temperature Degradation (LTD). A nanostructured 3Y‐TZP surface layer introduced in NNHYD by dip coating (DC‐NNHYD) improved resistance to LTD at the cost of reduced reliability under cyclic fatigue by increasing the stability of the tetragonal phase. This surface alteration highlights the impact of surface properties on mechanical performance. The results of this study present practical possibilities to help achieve the ideal balance between strength, toughness, and LTD resistance to improve the lifetime of zirconia‐based biomaterials. [ABSTRACT FROM AUTHOR]

Hybrid organometal halide perovskites (HP) present exceptional optoelectronic properties, but their poor long‐term stability is a major bottleneck for their commercialization. Herein, a solvent‐free approach to growing single‐crystal organic nanowires (ONW) is presented, along with nanoporous metal oxide scaffolds and HP, to form a core@multishell architecture. The synthesis is carried out under mild vacuum conditions employing thermal evaporation for the metal‐free phthalocyanine (H2Pc) nanowires, which are the core, plasma‐enhanced chemical vapor deposition (PECVD) for the TiO2 shell, and co‐evaporation of lead iodide (PbI2) and methylammonium iodide (CH3NH3I/MAI) for the CH3NH3PbI3 (MAPbI3/MAPI) perovskite shell. A detailed characterization of the nanostructures by electron microscopy, (S)‐TEM, and X‐ray diffraction, XRD, is presented, revealing a different crystallization of the HP depending on the template: while the growth on H2Pc nanowires induces the typical MAPI tetragonal structure, a low‐dimensional phase (LDP) is observed on the 1D‐TiO2 nanotubes. Such a combination yields an unprecedentedly stable photoluminescence emission over 20 h and over 300 h after encapsulation in polymethyl methacrylate (PMMA) under different atmospheres including N2, air, and high moisture levels. Moreover, the unique 1D morphology of the system, together with the high refractive index, allows for a strong waveguiding effect along the HP nanowire length. [ABSTRACT FROM AUTHOR]

Plasmonic nanomaterials with multiple components and designed structures show diverse properties and functions owing to the synergistic effects of the different components. Engineering the compositional and structural complexity of plasmonic nanomaterials is a powerful technique for expanding their range of applications. A facile approach to an unprecedented dart‐like type of nanostructure with AgPd bimetal selectively deposited at one end of Au nanobipyramids, forming AgPd nanodarts, is reported here. The synthetic process involves both galvanic replacement and Ostwald ripening. The morphological evolution of the AgPd nanodarts is thoroughly investigated and the growth mechanism is put forward. The as‐obtained AgPd nanodarts exhibit an outstanding photothermal conversion efficiency and peroxidase activity, which make them powerful for photothermally–catalytically combined tumor organoid ablation. In addition, two types of AgPd nanodart‐derived single‐end nanostructures, AgPd@ZIF‐8, and AgPd@TiO2 nanodarts, are prepared for the first time. The ZIF‐8 and TiO2 shell are preferentially coated at the AgPd end of the AgPd nanodarts, respectively. Both AgPd@ZIF‐8 and AgPd@TiO2 nanodarts show superior antimicrobial activities. The protocol and concept of modulating the structure of the nanodarts in this work can be extended to the development of a new class of plasmonic nanostructures with multifunctionalities. [ABSTRACT FROM AUTHOR]

New nanostructures betokening new nanotechnology and nanoscience. In this work, novel one-dimensional (1D) Y2(Zr0.6Ti0.4)2O7:Eu tube-in-tube nanostructures were fabricated by a simple single-nozzle electrospinning method. The Y2(Zr0.6Ti0.4)2O7:Eu double-layered nanotube consisted of an outer tube with a diameter of 250–340 nm and an inner tube with a diameter of 80–110 nm. The wall thickness of the outer tube is ∼30 nm. The wall thickness of the inner tube is ∼25 nm. The key to this technique is to utilize the difference in hydrolysis rates between the titanium source and the zirconium source in an air atmosphere with a humidity of 40–45% to obtain nanoscale tube-in-tube structures. The Y2(Zr0.6Ti0.4)2O7:Eu tube-in-tube nanostructures exhibit excellent luminescence stability and lower color drift performance at high temperatures. [ABSTRACT FROM AUTHOR]

Polymer templates are critical in the preparation of ceramic fibers from precursor solutions, but the available options are limited. Here, ZrO 2 nanofiber films and aerogels are developed by solution blow spinning method using hydroxypropyl methylcellulose (HPMC) and polyvinylpyrrolidone (PVP) as templates. The effects of HPMC ratio, polymer concentration, and calcination temperature on the morphology and structure of the ZrO 2 nanofibers are investigated. The nanofiber films with an areal density of 20 mg cm−2 exhibit excellent filtration property, achieving a filtration efficiency of 94.94% and a pressure drop of 136 Pa at an airflow velocity of 32 L min−1. The nanofiber aerogels display low density of 50 mg cm−3, low thermal conductivity of 0.039 W m−1 K−1, as well as superior compressibility, demonstrating significant potential for thermal protection applications. This work expands the formation template option of ceramic fibers, offering significant guidance in the development of flexible, high-temperature-resistant ceramic fiber materials. [ABSTRACT FROM AUTHOR]

In this paper, the nano silicon carbide with different sizes was prepared without hydrofluoric acid by using simple milling and related low temperature etching process in normal pressure. Also, it was the first time verified that 3-C dominated crystalline form of polycrystalline silicon carbide is etched, leaving the 6-H silicon carbide crystalline form by the Raman spectra and HAADF-STEM (high-angle-annular dark-field scanning transmission electron microscopy) imaging that. The application of the alkali etching technique could precise control the partial structural transformation of silicon carbide crystals to a certain extent, which further expands the traditional crystal structure transformation process. In addition, this paper demonstrates the silicon carbide composites in photocatalytic removal of various organic pollutants from aqueous solutions. In the photo degradation of MB (Methylene Blue), the removal rate of the modified silicon carbide shown ten times as much as the commercial silicon carbide. The 1-h degradation efficiency was significantly higher in the 50 μL H 2 O 2 system (100.0%, 86.8% and 89.9% removal of MB, Rhodamine B, Methyl Orange and Tetracycline hydrochloride, respectively). Furthermore, the unit spin concentrations of vacancy defects, superoxide radicals and hydroxyl radicals were quantitatively analyzed. The vacancy defects of the etched material were 1000 times higher than before, and the modified silicon carbide had higher transmittance to infrared and visible light. It strongly absorbs ultraviolet light. Conversely, the research on micron-sized silicon carbide loaded with Ag and Pt atoms found that it had a nitrogen fixation effect during the warming up process, in a nitrogen atmosphere. [ABSTRACT FROM AUTHOR]

Magnetic fields are uniquely valuable for creating colloidal nanostructured materials, not only providing a means for controlled synthesis but also guiding their self‐assembly into distinct superstructures. In this study, a magnetothermal process for synthesizing hybrid nanostructures comprising ferrimagnetic magnetite nanorods coated with fluorescent perovskite nanocrystals is reported and their magnetic assembly into superstructures capable of emitting linear and circularly polarized light are demonstrated. Under UV excitation, the superstructures assembled in a liner magnetic field produce linear polarized luminescence, and those assembled in a chiral magnetic field exhibit strong circularly polarized luminescence (CPL) with a glum value up to 0.44 (±0.004). The CPL is believed to originate from the dipolar interaction between neighboring perovskite nanocrystals attached to the chiral assemblies and the chiral‐selective absorption of the perovskite emission by the magnetite phase. The magnetic synthesis and assembly approaches and the resulting distinctive chiral superstructures are anticipated to open up new avenues for designing diverse functional chiroptical devices. [ABSTRACT FROM AUTHOR]

Plasmonic nanostructures are frequently utilized to create metasurfaces with a large variety of optical effects. Control over shape and positioning of the nanostructures is key to the function of such plasmonic metasurfaces. Next to lithographic means, directed self‐assembly is a viable route to create plasmonic structures on surfaces with the necessary precision. Here, a combined approach of DNA origami self‐assembly and electron beam lithography is presented for determinate positioning of gold nanospheres on a SiO2 surface. First, DNA origami structures bind to the electron beam‐patterned substrate and subsequently, gold nanoparticles attach to a defined binding site on the DNA origami structure via DNA hybridization. A sol‐gel reaction is then used to grow a silica layer around the DNA, thereby increasing the stability of the self‐assembled metasurface. A mean yield of 74% of single gold nanospheres is achieved located at the determinate positions with a spatial position accuracy of 9 nm. Gold nanosphere dimers and trimers are achieved with a rate of 65% and 60%, respectively. The applicability of this structuring method is demonstrated by the fabrication of metasurfaces whose optical response can be tuned by the polarization of the incoming and the scattered light. [ABSTRACT FROM AUTHOR]

The creation of SERS‐active substrates is investigated by self‐assembling hierarchical structures of plasmonic‐assisted nanospheres (HSNs). The hierarchical architecture exploits the advantages of the well‐known ordered configuration of a hexagonally closed‐packed array (CPA) of nanospheres. A further layer of upper nanospheres is used to provide regular and intense surface hotspots, located at the nanogaps between neighboring nanospheres. Numerical analysis is carried out to predict the SERS performances and to identify the more promising configurations, by offering design criteria and a physical insight on the conditions affecting the SERS response of the self‐assembled substrates. Two alternative self‐assembly fabrication methods have been pursued to realize HSNs, namely co‐deposition and sequential deposition. Morphological analysis revealed the formation of well‐ordered hierarchical structures with different ratios between the diameters of the bottom and upper nanospheres. Experimental analysis of the SERS response demonstrates that HSNs can work as cost‐effective SERS substrates with superior performances with respect to the simpler single‐layer CPA configurations. [ABSTRACT FROM AUTHOR]

Enantiomer sorting greatly promotes the advancement of chemistry, bioscience, and medicine while also facing significant challenges. Recently, all-optical solutions have attracted considerable interest due to their non-invasiveness. While, it should be noted that the achiral optical force is always much larger than the chiral gradient force that plays a key role in all-optical enantiomer sorting, hindering the separation of enantiomers. Previously proposed methods to boost the chiral gradient forces by plasmonic and photonic nanostructures are often accompanied by the enhancement of achiral optical forces. The sorted chiral particles are also difficult to be transferred from the complex nanostructures. Here, we propose an approach for separating enantiomers using uniform light field formed by two waves, which is capable of sorting deep sub-wavelength chiral particles. In our method, the chiral particles can be sorted within a simple planar structure while the achiral gradient force is equal to zero. Our research reveals a promising perspective on large-scale sorting for enantiomers. [ABSTRACT FROM AUTHOR]

Over the past few decades, chemical vapor deposition (CVD) of [2.2]paracyclophanes has captured significant attention as an emergent technology, producing conformal, chemically pure, and pinhole‐free coatings for biomedical and industrial applications. Compelling examples range from functional CVD polymers to tailored nanostructures. In this work, the unique functional properties of polymers derived from [2.2]paracyclophanes are connected with emergent applications. Special attention is given to the function‐property relationships in the areas of electronic materials, biomaterials, and separation materials. A particular focus is to highlight the versatility of CVD polymerization to process these polymers. [ABSTRACT FROM AUTHOR]

For the first time, the S-doped g-C 3 N 4 nanostructures (SCN(x)) were prepared by the reflux method as an aqueous-based method with different weight ratios of Na 2 S (x) and then characterized. The results of S-doped g-C 3 N 4 nanostructures confirmed the presence of sulfur doping in the g-C 3 N 4 structure. Moreover, these nanostructures showed superior photocatalytic efficiency compared to the bulk g-C 3 N 4. Among different SCN(x) nanostructures, SCN(0.2) showed the most remarkable photocatalytic performance. This outcome is attributed to a decrease in the band gap of this sample. The FESEM analysis indicated that the nanoparticles tended to adhere together in SCN(0.2) nanostructure. This phenomenon has led to the reduction of surface roughness, and improving the surface texture quality of this nanostructure. On the other hand, the lowest FWHM and PL peak intensity show an increase in crystallinity and a decrease in the amount of recombination in this nanostructure. Moreover, the evaluation of electrochemical impedance and optical current showed a decrease in the semi-circular pattern and an increase in photocurrent for the optimal sample of SCN (0.2) compared to the bulk g-C 3 N 4. Therefore, the results of investigating the photocatalytic performance of the synthesized nanostructures show that the SCN(x) nanostructures have higher efficiency compared to the bulk g-C 3 N 4. In addition, the SCN(0.2)) sample showed the highest photocatalytic efficiency. Compared to the other conventional deposition methods based on electrostatic or van der Waals forces, this study suggests that using the reflux technique to substitute sulfur in the g-C 3 N 4 can be a successful approach due to the chemical bonding on to host framework. Moreover, this method may provide a facile aqueous-based route for doping in the g-C 3 N 4 layered structure and can offer advantages compared to other common method such as simple, low cost, excellent distribution uniformity, fast reaction kinetics, high levels of purity, and environmentally friendly process. [ABSTRACT FROM AUTHOR]

Here in the present work, simple, eco-friendly and economical method of synthesis has been approached known as hydrothermal synthesis that allowed easy doping of Fe ions into the ZnS host lattice. A unique approach was adopted for the first time to prepare ZnS material where thioglycolic acid (TGA) was used as a source for sulfur in addition to a reducing and capping agent. Properties of the nanostructures were explored using different techniques. The X-ray diffraction (XRD) results indicated formation of single phase hexagonal ZnS material where inclusion of Fe2+ ions into the ZnS lattice have no influence on the crystal phase of the material. Probably almost identical sizes of Zn2+ and Fe2+ ions made this possible that indicated Fe2+ ions take Zn2+ vacant sites by substitution of Zn2+ ions by Fe2+ ions. Chemical analysis (X-ray photoelectron spectroscopy) performed discovered that Zn and Fe ions were present in +2 oxidation states whereas S is in −2 state. Anisotropic growth of the nanostructures is reported where irregular shaped nanostructures of varying dimensions were formed that agglomerated as doping concentration was increased to form spherical microstructures. Inclusion of Fe ions into the host material modified magnetic behavior of the nanostructures converting diamagnetic ZnS into a ferromagnetic material. Optical properties were also influence by the doping resulting in photon absorption at different wavelengths. The band gap got reduced from 3.2 eV to 2.7 eV making the ZnS nanostructures visible light active. The nanostructures with band gap 2.7 eV exhibited good photocatalytic activity against methylene blue (MB) dye under visible light illumination degrading 94% of the dye in just 2 h. The scavenging experiments performed showed hydroxyl free radicals play an active role in mineralizing the dye. Reusability and post photocatalytic properties of the photocatalysts determined their stability and potential ability for possible commercialization. [ABSTRACT FROM AUTHOR]

The article presents a new method for synthesizing porous metal- and metalloid-based nanomaterials using the NaK alloy as a versatile reagent. This approach eliminates the need for additional reagents and allows for the production of functional materials with controllable porous structures. The materials have potential applications in catalysis, energy storage, and green chemistry. The study also demonstrates the use of the materials in Na- and K-ion batteries, achieving good cycling stabilities and capacities. The proposed synthetic approach is scalable and versatile, making it suitable for various applications. [Extracted from the article]

The study of physical properties of compound semiconductors plays a vital role in the device fabrication point of view. Different investigations suggest that one can tune these properties by impurity dopants, irradiation techniques, adopting different synthesis techniques, etc. In this study, the physical properties of nanostructured thin films of Se–S compound were tuned by different Hg dopant concentrations. X-ray diffraction spectra clarify the preferred crystallite growth occurs in the cubic phase of the corresponding Bravi’s crystal system. The particle size calculated from Bragg’s reflection spectra by using Scherrer’s analytical formula illustrates an enhancement of crystallite size in highly concentrated Hg-doped sample. Similar consequences are found in surface morphological micrographs. The optical band gap reduced from 1.65eV to 1.54eV on increasing the doping concentration of Hg, according to the computed optical parameters using optical transmission spectra in the wavelength range 200–1100nm. The thin-film refractive index dispersion data fits well in accordance with the single oscillator model. Investigation of electrical properties tells that there is significant improvement in electrical conductivity in highly concentrated Hg-doped samples. Therefore, the apparent tuning as observed in the physical properties of the investigated material may have practical uses in industry for a variety of optoelectronic devices. [ABSTRACT FROM AUTHOR]

The current work aims to explore the structural and optical properties of Cu1−xNixO/ZnO nanostructured heterojunctions for optoelectronic applications. ZnO nanostructures and different Cu1−xNixO/ZnO (x; 0, 0.05, 0.10, 0.15 and 0.20) nanostructured heterojunctions were prepared by spray pyrolysis procedure on glass substrates. The surfaces morphology of the samples was examined by a scanning electron microscope (SEM). The energy dispersive X-ray (EDX) microscope was utilized to examine the elemental analysis. The XRD measurements show that ZnO nanostructures possess a hexagonal wurtzite structure, while Cu1−xNixO nanostructures possess monoclinic structures. The FT-IR spectroscopy was performed to explore the chemical bondings and functional groups. The UV–visible-NIR spectrophotometer was used to investigate the optical properties. The optical constants (refractive index, extinction coefficient, dielectric constants, optical conductivity) of the prepared samples have been investigated. The first-order linear optical susceptibility, third-order optical susceptibility and nonlinear refractive index are also studied. The obtained results show that the optical parameters of Cu1−xNixO/ZnO heterojunction could be tuned through controlling the Ni content. These novel findings nominate Cu1−xNixO/ZnO nanostructured heterojunctions for a plenty of optical, photocatalytic and optoelectronic applications. [ABSTRACT FROM AUTHOR]