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Converting CO2 to valuable materials is attractive in environmental protection and resource utilization. In this study, a vapor–liquid interface reaction system for mass production of high-quality graphene is reported. The graphene obtained has high crystallinity and few defects during the reaction of CO2 and Mg melt. The growth mechanism of graphene is demonstrated in vapor–liquid interface area by combining the CO2 bubbles as a soft template to guide growth with the confinement effect of dense MgO nanoparticles. The quality of the graphene is verified by epoxy composites with high electromagnetic shielding effectiveness. Additionally, the V–L reaction method ingeniously solves the dispersion of graphene in metal, providing a preparation strategy of Mg matrix composites with structure and function integration.

Variations on the processing conditions of conventional methods for polymeric film preparation may allow tuning certain properties. In this work, different casting surfaces and humidity are presented as variables to consider for cellulose acetate (CA) film preparation using conventional solution casting method. Specifically, borosilicate glass, soda-lime glass and Teflon (PTFE) dishes have been used for casting and their influence on various properties on CA films assessed. The surfaces of glass dishes are smooth, while PTFE surface has a pattern constituted by concentric channels of micro dimensions (as seen by optical microscope), which is adopted by cast films upon drying. The resulting patterned films are translucent while films produced using smooth surfaces are transparent. The effect of the environment humidity (35%, 55% and 75% RH) in the properties of the CA films during the evaporation of solvent from solution has been evaluated. Higher humidity produces smoother surfaces and increased crystallinity as shown by XRD and DSC; however, the wettability of the films does not seem to be influenced by this variable. Due to the specific morphology of the patterned films, changes in material opacity upon wetting are detected, from translucent to transparent, while the removal of water from the surface restores the translucency. This micropatterning effect that causes different visual appearance of the material can find use as a humidity sensor in food packaging applications.

This work deals with the study of the effect of the irregular crumbling (Instability of cutting) for recycled polyethylene terephthalate (PET) bottles on the extrusion process using a twin-screw extruder and as a result its effect on the mechanical properties of the product and the amount of electrical energy consumption. The extrusion process was performed for cutting sizes of PET bottles (4.75, 6.75, 7.15, and 10 mm) in addition to raw material to compare, at temperature ranges between (200–205 °C) at speed of 50 rpm. Results showed that the cutting size has a direct effect on the crystallinity which affects mechanical and thermal properties, such as elongation and tensile strength decreases with increase cutting size but the elastic modulus increase with increase cutting size. The impact and hardness test proved that the impact strength and hardness decrease with increase cutting size, also, it was observed during the extrusion process when placing an equal amount of different sizes in the machine and ensure that the materials enter the machine at once for the sake of comparison, we find that the lower volumes consumed less electrical energy, compared to the rest of the other different sizes, except the raw material from (PET).

This research explores a segment of the mechanical, thermal & physical characteristics of a polymer polypropylene (PP) mixture including low density polyethylene (LDPE). There were mixing syntheses (pure PP, 25 LDPE/75PP, 50LDPE/50PP, 75LDPE/25LDPE, pure PP) that were examined. As outcome, the expansion of LDPE to PP has decreased, with improved thickness, elasticity, bending efficiency, versatile modulus and hardness. In a (25LDPE/75PP) arrangement the prevailing elasticity was achieved while the (50LDPE/50PP) synthesis was attributed to ideal bent efficiency. High density polyethylene (HDPE) blowing in different proportions PP/polyethylene (PEs) can remove sorting course employed during even recycling course. PP has interesting features like outstanding process ability &tolerance to chemicals. Inadequate versatility, however, limits its usage in specific applications. Mixing PP with relative PEs may enhance its versatility. Universal kinetics of PP crystallization have been affected greatly by the existence of PEs of various structures of the ramifications. Existence of LDPE reduced overall summation ratio while HDPE increased the process of crystallization. No negative effect was observed in the studied parameter range on mechanical performance and the related crystallinity.

Polyvinylidene fluoride (PVDF) nanofibers with cellulose nanocrystals (CNCs) were produced with the electrospinning technique at the CNC loading rates of 0.25, 0.50, 0.75, and 1 wt%. CNCs were obtained with acid hydrolysis of microcrystalline cellulose with 64 wt% sulfuric acid. The material properties of CNCs have been studied with scanning electron microscopy (SEM), transmission electron microscopy, atomic force microscopy, X-ray diffraction (XRD), thermal analysis (TGA), ultraviolet (UV-Vis) spectroscopy, and fourier transform infrared spectroscopy. The PVDF nanofibers with CNCs were produced by the electrospinning technique. The material characterization of neat PVDF and the PVDF-CNC nanofibers were investigated with XRD, TGA, FT-IR, and morphological properties with SEM. The morphological results showed that CNCs were observed as needle-shaped rods and lengths for CNCs were generally in the range of 25-50 nm and 150-300 nm. The crystallinity and crystal size of CNCs were calculated as 75% and 4.8 nm, respectively. CNCs showed the decomposition stages at 100-250 degrees C and 300-375 degrees C for the evaporation of the water and decomposition reactions of cellulose, respectively. CNCs exhibited a weak absorbance at 265 nm according to the UV-Vis. As seen in the results of the nanofibers, it was found that CNCs generally decreased the diameters of the nanofibers obtained with the electrospinning when the loading rates of CNCs were raised. The presence of CNCs generally improved the thermal stability of the nanofibers. XRD results showed that crystallinity generally increased with adding CNCs. In FT-IR spectra, any difference was not detected among the PVDF-CNC nanofiber spectra.

The sub-micrometer sized TiO2 particles (100~200 nm) were synthesized by a sol-gel and subsequent thermal annealing. The particle size, surface area, pore structure, and crystallinity were varied upon the annealing temperatures (450, 550, 650 oC). The photocatalytic activities of three TiO2 particles annealed at various temperatures (450-, 550-, and 650-TiO2) were examined by performing photocatalytic depollution of three organic model pollutants (methylene blue, methyl orange, and phenol) from aqueous solutions under the UV light irradiation. Among three samples, 550-TiO2 (~200 nm) exhibited the highest photocatalytic activity towards the removals of all three model pollutants. Photocatalytic activity of the 550-TiO2 was compared with a commercial TiO2 (P25, Evonik) at various conditions of loading amounts of particles dispersed in MB solution. Light scattering by dispersed particles at high sample loading conditions was less pronounced in the case of 550-TiO2. Therefore, the sub-micro 550-TiO2 particles can exhibit comparable activity to P25 at high sample loading conditions (2-4 g/L). In addition, the bigger size of 550-TiO2 made it possible to separate them via a simple sedimentation process, showing a potential of sub-micro TiO2 particles as an efficient photocatalysts for water depollution.

Hydroxyapatite (HAp) is the major component of all boney tissues in mammals. Because of this omnipresence in the living world, HAp possesses an exceptional biocompatibility. The downside of this omnipresence, however, comes in the form of its mild to moderate biological activities. One means of augmenting these activities involves the doping of HAp with foreign ions. Here, the first synthesis and characterization of HAp doped with germanium ions is being reported. Germanium was deliberately integrated into the crystal lattice of HAp in the form of germanate anions. Approximately two thirds of the germanate ions introduced into the hydrothermal solution got incorporated into the HAp lattice, yielding the approximate stoichiometry of Ca10-x(PO4)5.62+y(GeO3)0.38(OH)2-z. Germanates replaced the phosphates of stoichiometric HAp and induced the expansion of the HAp lattice both along the screw axis of the calcium ion hexagons and in the direction parallel to the basal plane. Simultaneously, the larger size and the triple valency of the germanate ion as compared to the smaller and trivalent phosphates prompted the bond distortion and charge compensation through defect formation, which reduced the crystallinity and increased the microstrain of the HAp lattice. Vibrational spectroscopic analyses corroborated these crystallographic effects by demonstrating the enhanced heterogeneity of the environments surrounding the active modes after germanate ions were incorporated into HAp. Conforming to La Châtelier's principle, this reduction of the crystallographic order increased the capacity of the material for integration of adventitious carbonates. However, the inclusion of germanate ions induced a partial shift of these carbonates to the hydroxyl channel sites, thus decreasing the ratio of the B-type carbonation to the A-type carbonation. Introduced into HAp, germanium acted as a superb regulator of the particle size and morphology, enhancing their fineness and uniformity. Inclusion of germanate ions also increased the electrophoretic mobility and hydrodynamic surface charge density of the particles by reducing their size and by inducing a more stochastic distribution of terminal ionic groups due to the bending of the crystal facets. Overall, the doping of HAp with germanate ions facilitated the production of narrowly dispersed nanorods with a moderately enhanced structural disorder and with a pronounced potential for the biomedical niche. © 2022 The Author(s)

Calcium phosphates are biomaterials widely used in bone tissue engineering. In recent years, the alternative of obtaining these materials with antimicrobial properties, has been explored due to the multiple advantages that this would imply in the design of devices or implants that prevent the failure of these associated with bacterial colonization. The goal of the present work was obtaining gold nanoparticles supported on biphasic calcium phosphates (BCPs) with high crystallinity by one-step solution combustion technique, and with antimicrobial response, a fact that can significantly reduce the production cost of these materials. X-ray diffractograms (XRD) showed that prepared powders have high crystallinity owing to high temperatures during the combustion reaction, also Rietveld refinement showed that the inclusion of gold nanoparticles (AuNPs) influenced the phases’ ratio obtained. Furthermore, scanning electron microscopy (SEM) showed agglomeration of particles with morphologies with shape tending to be equigranular, while the presence of AuNPs was corroborated by transmission electron microscopy (TEM). All samples that were obtained in a single step, by solution combustion, showed antimicrobial behavior validated through the inhibition halos, whereas particles subjected to thermal treatment lost their antimicrobial response.

In this study, porous carbon has been prepared through potassium hydroxide (KOH) activation of coconut fiber (CF) and subsequent carbonization in the presence of an inert gas. The activated carbons (AC) were prepared via carbonization of the precursor at different temperatures. Subsequently, their electromagnetic wave absorption (EMWA) performance was investigated at X-band frequency. The phase crystallinity, porous features, and degree of graphitization of the activated carbons were studied using XRD, nitrogen adsorption/desorption isotherm, and Raman spectroscopy, respectively. Using the BET method, the activated carbon prepared at 750 °C displayed a high specific surface area of 602.9 m2 g−1 and an average pore size of 6 nm, which confirms the extant of mesopores. The EMWA was studied using COMSOL Multiphysics software based on the finite element method. Results show that the activated carbon prepared at 750 °C attained an optimal reflection loss of −45.6 dB at 10.96 GHz with a corresponding effective bandwidth of 3.5 GHz at a thickness of 3.0 mm. In conclusion, this study interestingly shows that porous carbon obtained from coconut fiber has great potential for attenuating electromagnetic waves.

The structure of carbon black (CB) is investigated during its oxidation by O2 at 550 and 800 ◦C by thermogra vimetric analysis, microscopy, N2 adsorption and X-ray diffraction (XRD). That way, the dynamics of its porosity and crystallinity during surface and internal oxidation are elucidated, for the first time to the best of our knowledge. At 800 ◦C, oxidation takes place largely on the CB surface. This increases the CB specific surface area, SSA, from 240 to about 453 m2 /g, closely following the classic shrinking particle model and hardly affects the porosity and crystallinity of CB. At 550 ◦C, O2 diffuses and reacts with the bulk of CB particles forming pores with radius smaller than 2 nm after 25 and 50% conversion. At higher conversions, these small pores fuse together resulting in hollow CB particles with high SSA, up to 939 m2 /g. Fractal and XRD analyses of the resulting pore network reveals that internal oxidation at 550 ◦C reduces the interlayer distance of the crystallites constituting the CB, compacting its pore network. This increases the pore fractal dimension, Dfp, from 2.43 up to about 2.7, in good agreement with the Dfp measured during diesel soot oxidation. The dynamics of CB porosity and crystal linity quantified in detail here can assist the design of new highly porous CB grades and activated carbons as well as battery materials., Carbon, 197, ISSN:0008-6223

Researchers have long sought to predict the mechanical behavior of polyethylene from its microstructure. In particular, the yield strength and yield kinetics have been reported to be dependent on crystallinity and crystal thickness, but the relative importance of these two microstructural attributes has not been shown. In the present work, a series of microstructures was obtained through a combination of controlled quench rates from the melt and inclusion of various amounts of hexene comonomer. The yield strength for a wide range of strain-rates was linearly dependent on the crystallinity, and independent of crystal thickness (chain stem length), both measured by Raman spectroscopy. Similarly, yield kinetics described by a Ree-Eyring two-process stress activated model showed linear dependence on crystallinity and no dependence on crystal thickness. The results of the present work call into question models of yield kinetics dependent on screw dislocation nucleation, which depend on crystal thickness.

Rare earth (RE) pentaborates, both α- and β-polymorphs, are good candidates for photoluminescent hosts suitable for various RE activators. Ce3+ acts not only as an activator itself, but also as a sensitizer to other rare earth activators, like in the case of commercial green phosphor CeMgAl11O19:Tb3+. In this work, two solid solutions of β-La0.9–xCe0.1TbxB5O9 (0 ≤ x ≤ 0.15) and β-La0.9–yCe0.1DyyB5O9 (0 ≤ y ≤ 0.07) were prepared by sol–gel method with high crystallinity, and the phase purity was confirmed with careful analyses on powder X-ray diffraction patterns. Energy transfers are expected due to the overlapping of Ce3+ emission with the Tb3+/Dy3+ excitation. Indeed, the steady photoluminescence spectra indicate the decrease of the Ce3+ emission and the increase of the Tb3+/Dy3+ emission, and the fluorescence decay curves exhibit the decrease of the average lifetime of Ce3+. The energy transfer efficiency is estimated to be 60% at x = 0.15 and 55% at y = 0.07, respectively. The mechanism is likely through the dipole–dipole electric interactions for both cases. With this rationale, the Tb3+ and Dy3+ emissions are greatly enhanced, in particular, the white emission of Dy3+ in β-La0.85Ce0.1Dy0.05B5O9 is enhanced by 20 times.

Al-based MIL-53 MOF nanostructure was synthesized hydrothermally and then co-deposited in the electroless nickel coating on AM60B magnesium alloy using Zr pretreatment as an eco-friendly underlayer. The MIL-53(Al) nanostructure was synthesized in the form of layered semi-cube crystals with the surface area and mean pore diameter of 985.72 m2g−1 and 2.00 nm, respectively. The SEM images captured with two various zooming scales from the surface of the plain and MOF containing electroless layers showed cauliflower-like morphology with even distribution of nodule size. Also, the sub-grains of the plain coating disappeared after incorporation of the MOF. Although, both the normal and nanostructure-containing electroless layers have crystalline-amorphous structure, but the nanocomposite coating showed less crystallinity. The average surface roughness of the plain electroless coating was about 309 nm, which decreased to about 222 nm after incorporation of the MOF. The XRD patterns showed that the characteristic peak of Ni broadened after incorporation of the MOF, probably due to the decreasing of the crystallinity. For the heat-treated normal and MOF containing coatings at 200 °C no phase transition takes place, but new peaks appeared for heat-treated coatings at 400 °C due to the crystallization and second-phase precipitation. The results of the EIS tests showed an increase in the amount of the charge transfer resistance (from 19 to 29 kΩ cm2) after addition of the MOF, which means an improvement in the corrosion resistance. Also, low Jcorr of the composite coating represents its higher corrosion resistance with respect to the plain coating. The micro-hardness values of the composite coating before and after the heat treatment were higher than the plain coating. Also, the Ni-P-MOF coating has a lower wear rate both before and after the heat treatment due to an improvement in its micro-hardness.

Microplastics (MPs) pollution is becoming a global environmental problem due to the ubiquity. Knowledge about transformation process of MPs under ultraviolet (UV) irradiation was critical to understanding the environmental fate of these particles. In this study, the photo-aging characteristics and mechanisms of polyvinyl chloride (PVC) under different UV irradiations in the air or water condition were comprehensively investigated. When the PVC was exposed to the UVA, UVB and UVC irradiation, the surface morphology, functional group, crystal structure, and elemental composition of PVC were systematically characterized. With the increasing of aging time, the PVC was identified as more oxygen-containing functional groups, higher carbonyl index, and higher crystallinity, especially under the UVC irradiation. Based on the Two-dimensional correlation Fourier transform infrared spectroscopy (2D-FTIR-COS), the active sites and aging sequence of functional groups were confirmed under UVA, UVB and UVC irradiation. The reactive oxygen species (ROS) were produced and increased with the aging time as the whole. Corresponding to the aging results, the intensity of ROS and toxicity from leaching under UVC irradiation was greater than that under UVA or UVB. These findings provide direct evidences of photo-aging processes of MPs and the potential ecological risks resulting from aging in the aquatic environments.

This work examines the significance of the degree of polyethylene terephthalate (PET) crystallinity (XC) and glass transition temperature (Tg) on enzymatic degradation of PET at elevated temperatures using two engineered, thermostable PET degrading enzymes: LCCICCG, a variant of the leaf-branch compost cutinase, and DuraPETase, evolved from the Ideonella sakaiensis PETase. XC was systematically varied by thermal annealing of PET disks (Ø 6 mm, thickness 1 mm). XC affected the enzymatic product release rate that essentially ceased at XC 22-27% for the LCCICCG and at XC ∼17% for the DuraPETase. Scanning Electron Microscopy revealed that enzymatic treatment produced cavities on the PET surface when XC was >10% but resulted in a smooth surface on amorphous PET (XC ∼10%). The Tg of amorphous PET disks decreased from 74°C to 61°C during 24 h pre-soaking in water at 65°C, while XC remained unchanged. Enzymatic reaction on pre-soaked disks at 65°C, i.e. above the Tg, did not affect the enzymatic product release rate, but delayed the initiation of enzymatic attack despite the lower Tg compared to enzymatic reaction on un-soaked samples. The data suggest that extended soaking of PET at 65°C induces an increase in the rigid amorphous fraction (XRAF) that impedes the enzymatic attack. These findings improve the understanding of enzymatic PET degradation and have implications for development of efficient enzymatic PET upcycling processes.

Purpose: Traditional dosage forms of granisetron (GRN) decrease patient compliance associated with repeated drug administration because of the short half-life of the drug. Methods: In this study, novel GRN-loaded Polylactic-co-glycolic Acid (PLGA) sustained-release microspheres were prepared for the first time via a dropping-in-liquid emulsification technique. The effects of various factors, such as pH of the outer phase, Tween 80, Polyvinyl Alcohol (PVA) concentrations, and hardening process, on the Encapsulation Efficiency (EE), Drug Loading (DL), and particle size of microspheres were extensively studied. The physicochemical properties, including drug release, surface morphology, crystallinity, thermal changes, and molecular interactions, were also studied. Results: GRN has a pH-dependent solubility and it exhibits a remarkably high solubility under acidic condition. The EE of the alkaline medium (pH 8) was higher than that of the acidic medium (pH 4.0). EE and DL decreased in the presence of Tween 80 in the outer phase, whereas EE significantly increased during hardening. The particle size of microspheres was not affected by PVA and Tween 80 concentrations, but it was influenced by PVA volume and hardening. X-ray diffraction and differential scanning calorimetry results showed that the physical state of the drug changed from a crystalline form to an amorphous form, thereby confirming that the drug was encapsulated into the PLGA matrix. Fourier transform-infrared spectroscopy confirmed that some molecular interactions occurred between the drug and the polymer. GRN-loaded PLGA microspheres showed sustained release profiles of over 90% on week 3. Conclusion: GRN-loaded PLGA microspheres with sustained-release were successfully prepared, and they exhibited a relatively high EE without Tween 80 as an emulsifier and with the hardening process.

Ferroelectric HfO2-based materials hold great potential for widespread integration of ferroelectricity into modern electronics due to their robust ferroelectric properties at the nanoscale and compatibility with the existing Si technology. Earlier work indicated that the nanometer crystal grain size was crucial for stabilization of the ferroelectric phase of hafnia. This constraint caused high density of unavoidable structural defects of the HfO2-based ferroelectrics, obscuring the intrinsic ferroelectricity inherited from the crystal space group of bulk HfO2. Here, we demonstrate the intrinsic ferroelectricity in Y-doped HfO2 films of high crystallinity. Contrary to the common expectation, we show that in the 5% Y-doped HfO2 epitaxial thin films, high crystallinity enhances the spontaneous polarization up to a record-high 50 µC/cm2 value at room temperature. The high spontaneous polarization persists at reduced temperature, with polarization values consistent with our theoretical predictions, indicating the dominant contribution from the intrinsic ferroelectricity. The crystal structure of these films reveals the Pca21 orthorhombic phase with a small rhombohedral distortion, underlining the role of the anisotropic stress and strain. These results open a pathway to controlling the intrinsic ferroelectricity in the HfO2-based materials and optimizing their performance in applications.

For the medical diagnosis, radiopaque materials (RM) made from high specific gravity elements like Pt, Au, Ta, Iodine, Bromine are either attached or blended or coated on an implant to makes it detectable under X-ray/Fluoroscopy/CT-Scan. RM facilitate the surgeon in an operation theatre to position an implant during the surgery. Mainly, RM are non-degradable, thus in case of biodegradable implants, it may detach from the body and accumulate in vital organ cause serious health issue. Therefore, a new bioresorbable radiopaque material (BRM) was produced by alloying the high specific gravity elements Zn (35% w/w) and Y(4% w/w) with Mg metal. In this alloy, three main phases were identified, alpha Mg, Mg7Zn3 and icosahedral quasicrystalline I-phase Mg3Zn6Y, which reinforce the Mg matrix. Hereafter, BRM was powdered to a size of less than 25microns and blended in different ratios with bioresorbable poly- l -lactic acid (PLLA) for fabricating PLLA/BRM bio-composite. BRM microparticles were uniformly distributed and interfacial bonded with the matrix. The X-ray was passed through bio-composite to capture µCT radiograph for evaluating linear attenuation co-efficient (µ) and optical density (OD). Thermal analysis reveals that BRM particles act as a nucleating site and enhance the crystallinity of the polymeric chain. During the In Vitro accelerated degradation study, the alkaline nature of BRM neutralise the acidity of PLLA and balance the pH of the body fluid to reduce the inflammatory reactions, but this compromises the stability of the polymer as it increases the decomposition rate.

Nanoporous crystalline aluminosilicates, zeolites, are synthesised by solvothermal method producing three-dimensional (3D) crystals. An alternative, more controllable approach of zeolite synthesis - ADOR – can be used for preparation of isoreticular zeolites with tuneable porosity. Zeolites porosity allows their wide use as isomerisation catalysts due to their shape selectivity effects. Selective isomerisation of m-xylene towards p-xylene is an industrially important reaction due to a high demand for the latter as a substrate for terephthalic acid production. In this work, we investigated the influence of pore size (shape selectivity effect) on the isomerization of m-xylene using a system of isoreticular Al-containing zeolites. These materials, prepared by ADOR approach (UTL, IPC-7, IPC-2, IPC-6, and IPC-4) had different layers connectivity, and therefore various channel systems. We tracked the influence of the pore systems of ADOR zeolites (8- up to 14-ring channels) on the catalytic performance in gas-phase m-xylene isomerisation. We investigated the crystallinity and interlayer distances, phase purity, textural properties of prepared materials, their crystals morphology, and aluminium content. M-xylene isomerisation was carried out in a fixed-bed reactor at 350 °C. ADOR catalysts were compared with standard ZSM-5 zeolite. We show the dependence of zeolite porosity on the performance in isomerisation of m- to p-xylene. Smaller pore zeolites: IPC-4 (8- and 10-ring channels) and IPC-6 (8-, 10- and 12-ring channels) exhibited the lowest conversions, while the highest conversion and p-xylene yields were observed for IPC-2 (10- and 12-ring channels). Presence of extra-large, 14-ring channels (IPC-7 and UTL) resulted in the drop of selectivity due to the xylene disproportionation.

Manipulating the structure self-reconstruction of transition metal sulfide-based (pre)catalysts during the oxygen evolution reaction (OER) process is of great interest for developing cost-effective OER catalysts, which remains a central challenge. Here we realize a deep structure self-reconstruction of natural chalcopyrite to unlock its OER performance via mechanochemical activation. Compared with the manually milled counterpart (CuFeS2-HM), the mechanically milled catalyst (CuFeS2-BM) with a reduced crystallinity exhibits a 7.11 times higher OER activity at 1.53 V vs. RHE. In addition, the CuFeS2-BM requires a low overpotential of 243 mV for generating 10 mA cm−2 and exhibits good stability over 24 h. Further investigations suggest that the excellent OER performance of CuFeS2-BM mainly originates from the decreased crystallinity induced the in situ deep structure self-reconstruction of the originally sulfides into the electroactive and stable metal (oxy)hydroxide phase (e.g., α-FeOOH) via S etching under OER conditions. This study demonstrates that regulating the crystallinity of catalysts is a promising design strategy for developing highly efficient OER catalysts via managing the structure self-reconstruction process, which can be further extended to the design of efficient catalysts for other advanced energy conversion devices. In addition, this study unveils the great potentials of engineering abundant natural minerals as cost-effective catalysts for diverse applications.

Air moisture is the key issue for perovskites which invades the films and accelerates the damage of devices. Here, polyvinylpyrrolidone (PVP) is introduced to the methylammonium lead iodide (MAPbI3) perovskite precursor to control crystal growth and endow the devices with self-healing ability in a moisture environment. The strong C=Ο⋅⋅⋅Η−Ν hydrogen bonding interactions between PVP and MAPbI3 was confirmed by nuclear magnetic resonance measurements. By introducing hydrogen bonding in the MAPbI3-based PSCs, we form a compact perovskite film of excellent electronic quality with a power conversion efficiency (PCE) of up to 20.32%. Furthermore, the Ο⋅⋅⋅Η−Ν hydrogen bonding interactions at the grain boundaries suppress the decomposition of methylammonium cations and improve the recyclable dissolution-recrystallization of perovskite. As a result, the MAPbI3-PVP based cells exhibited striking moisture stability and self-healing behavior, with negligible decay in efficiency after 500 h of operation in high humidity (65±5% relative humidity) and rapid recovering ability after their removal from the humid environment.

Covalent organic frameworks (COFs), as a novel class of functional polymers, exhibit versatile applications due to their crystalline porous structures and conjugated skeletons. However, synthesis of COFs with high crystallinity still faces great challenges, especially for scale-up preparation. Herein we report a two-step solvothermal process to improve crystallinity of COFs. The first step focuses on polycondensation of monomers with no need for optimizing crystallization conditions. In the second step, appropriate solvothermal conditions are used to facilitate crystallization of the COFs through defects correction and structural repairing. Furthermore, this strategy could also be applicable to scale-up synthesis of high quality COFs, which lays a foundation for their practical applications.

A series of large-area, flexible and transparent ultraviolet (UV) photodetectors (PDs) based on Ag nanowire (NW)@ZnO nanorods (NRs) are fabricated by an inexpensive, facile and effective approach. These Ag NW@ZnO NRs are successfully synthesized using a two-step method in an oil bath with a high surface-to-volume ratio and good crystallinity. The PDs are fabricated by drop-coating with different drop-coating times on the surface of polyethylene terephthalate (PET) coupled with Au electrodes. By optimizing the cross-linked network of Ag NW@ZnO NRs, PD2 with a size greater than 25 mm exhibits excellent photoresponse under UV light illumination of 365 nm (1.3 mW cm−2) with a bias of 5 V: a high sensitivity of over 103, and a much shorter rise/decay time of 2.6 s/2.3 s. Simultaneously, the detector exhibits an average transmittance of more than 70% in the visible light region, as well as good flexibility and excellent mechanical stability under a bending angle of 120 degrees over 1000 circles bending. These integral advantages have significant potential for practical applications and mass production.

The nonradiative recombination of charge carriers at the hole transport layer (HTL)/perovskite interface generally induces remarkable performance loss of the inverted two-dimensional perovskite solar cells (2D PSCs). Herein, a cross-linkable small molecule of 2-mercaptoimidazole (2-MI) was introduced into the nickel oxide (NiOx)/2D perovskite interface. Experiments have confirmed the formation of Ni-N covalent bond by N atom in the 2-MI and Ni in the NiOx and the coordinating between S atom of 2-MI and under-coordinated Pb2+ near to the NiOx/perovskite interface, which contributes to creating a cross-linking between NiOx/perovskite interface to restrain charge carrier recombination and enhance the extraction of hole carriers at the interface. Besides, the 2-MI modification layer is also beneficial for promoting the crystallinity of 2D perovskite. Consequently, the inverted 2D PSCs with 2-MI modification achieved the best power conversion efficiency of 15%. This paves a route to acquire highly efficient 2D PSCs by constructing a cross-linking at the NiOx HTL/2D perovskite interface.

In this study, the Ti/SnO2-RuO2 electrodes with different Yb contents were prepared by sol-gel method and thermal decomposition method, and the surface morphology and crystal structure of the electrodes were characterized by scanning electron microscopy (SEM), atomic force microscope (AFM) and X-ray diffraction (XRD), the electrochemical properties of the electrodes were tested by linear sweep voltammetry (LSV) and cyclic voltammetry (CV). The electrochemical oxidation device was constructed with Yb-doped Ti/SnO2-RuO2 electrode as the anode and titanium plate as the cathode, and the electrochemical oxidation effect and product changes of the anode on coking wastewater were investigated. The results show that the surface of the electrode is flat with high crystallinity of SnO2 and RuO2 crystals at 1.5% Yb doping, and the LSV and CV curves indicate that the rare earth doping of 1.5% increases the oxygen precipitation potential and electrocatalytic oxidation activity of the electrode. When the electrode with rare earth doping of 1.5% is the anode with current density of 10mA/cm2 electrochemical oxidation time of 30min, the electrode can remove COD up to 85.06%, TOC up to 60.59% and UV254 from 1.594 to 0.507 for coking wastewater. GC-MS, UV-vis and three-dimensional fluorescence results of coking wastewater before and after treatment show that large toxic substances in coking wastewater are degraded to low toxic organic substances, and most soluble organic substances are degraded and transformed. This study provides the possibility of basic research for the engineering practice of electrochemical oxidation for the treatment of coking wastewater.

Achieving high-quality perovskite films with uniform morphology and homogeneous crystallinity is challenging owing to the coffee ring effect (CRE) in the spray-coating technologies. In this study, an evaporation/spray-coating two-step deposition method is used to fabricate Cs0.19FA0.81PbI2.5Br0.5 light harvesters for perovskite solar cells (PSCs). Considering the solid-liquid reaction, we establish a reaction-dependent regulating strategy that inhibits CRE successfully and prepare a high-quality perovskite layer, wherein the solvent for the FAI/Br solution during the spraying process is changed from isopropanol to n-butyl alcohol (NBA). The retarded-drying-enhanced spreading of the NBA solution inhibits contact line pinning to suppress the capillary flows and increases the reaction between metal halides (CsI/PbI2) and organic salts (FAI/Br), which result in a reduction in the accumulation of solutes in the periphery effectively inhibiting CRE. Consequently, we obtain a high performance Cs0.19FA0.81PbI2.5Br0.5 PSC with a power conversion efficiency (PCE) of 19.17%. An enlarged perovskite film (10 × 10 cm2) containing 40 sub-cells is prepared. The average PCE of these devices is 18.33 ± 0.56%, proving the reliability of the “coffee ring” regulating strategy. This study provides an effective approach for CRE controlment in spraying technology to achieve high repeatability devices with good performance.

Lead-free Bi0.5Na0.5TiO3 piezoelectric ceramics were successfully prepared by reactive flash sintering of Bi2O3-NaCO3-TiO2 mixed powders, where phase transformation and densification occurred simultaneously. The influence of electric field strength, current density and holding time at constant current state on the phase transformation and densification were investigated. The current density had a significant influence on the extent of phase transformation and densification. The holding time had no influence on the phase transformation, but had an important effect on crystallinity of sample. The sintered bulks exhibited the maximum polarization Pm of 16.8 μC/cm2, remanent polarization Pr of 9.6 μC/cm2, coercive field Ec of 29 kV/cmm, maximum electric-field-induced strain of 0.053%, and piezoelectric coefficient d33 of 85 pC/N. The reactive flash sintering can prepare the dense and single-phase ceramics from multiphase precursor powders in one step of flash, providing a new way for rapid production of ceramic materials.

Magnetic materials with desired architectures and high performance have become increasingly important for applications. In this work, NiZn ferrites with mesh structures have been successfully fabricated from preliminary precursors by three-dimensional (3D) printing accompanied by the solid-state reaction. The influence of compositions on structural and magnetic properties of NiZn ferrites were systematically investigated. It was obvious that the saturation magnetization was significantly enhanced to 77 emu/g for NiZn ferrites with a zinc concentration of 0.4, which was a much higher value compared to Ni ferrites. This is attributed not only to the well-known cationic distribution, but also to the grain growth with extraordinarily high crystallinity. Consequently, NiZn ferrites with intricate mesh structures were utilized for magnetic separation, and the distributions of magnetic flux density were simulated. Overall, the fabrication of NiZn ferrites by 3D printing is attractive for scaled-up applications, and also paves the promising avenue for magnetic separation.

Solid-state electrolytes (SSEs), which replace flammable and toxic liquid electrolytes, have attracted widely attention. However, there exist still some challenges in actual application such as poor interfacial compatibility and slow ionic migration. In this study, MgO nanofibers and MgF2 nanofibers were prepared via the electro-blow spinning and high-temperature calcination methods, and were applied to all-solid-state lithium metal batteries for the first time. The organic-inorganic composite SSEs exhibited continuous conduction paths based on the virtue of the nanofibers with high length-to-diameter ratio, which were designed and prepared by mixing prepared fillers into the poly(ethylene oxide) (PEO)/ lithium bis(trifluoromethane) sulfonilimide (LiTFSI) system. The effect of filler with different morphologies, doping ratios and component on ionic conductivity, electrochemical stability and cycle performance were explored under two kinds of [EO]/[Li+] ratios and ambient temperatures. The ionic conductivities of electrolytes containing MgO and MgF2 nanofibers can reach up to 1.19×10−4 and 1.39×10−4 S cm−1 at 30 °C, respectively. They were attributed to specific ionic conductive enhancement at the organic-inorganic interface, reduced crystallinity and Lewis acid interaction, which can effectively promote the dissociation of the lithium salts. Especially MgF2 nanofiber, combining low electronic conductance, excellent electrochemical stability and outstanding inhibition for lithium dendrites of fluorides, endowed the battery with an initial specific capacity of 140.6 mAh g−1 and capacity decay rate per cycle of 0.055% after 500 cycles at 50 °C. The work can provide an idea to design SSE with fast and multi-dimensional Li conductive paths and excellent interfacial compatibility.

Phase change materials (PCMs) with ideal thermal property, has become a critical hallmark in thermal energy storage (TES). The phase change hysteresis (PCH) phenomenon is particularly prominent since the phase transition of PCM mixture non-isothermal. In this paper, a paraffin-based nanocomposite PCM were prepared, the multiwalled carbon nanotubes (MWCNTs) and sodium dodecyl benzene sulfonate (SDBS) were comprised for the enhancement of thermal conductivity and suspension stability. The PA/MWCNTs/SDBS composite PCM exhibited excellent chemical compatibility, better thermal storage capacity, high thermal charging and discharging efficiency, and preferable thermal and cyclic stability through a series of characterization. Furthermore, the differential scanning calorimetry (DSC) was performed to investigate the association of temperature range, temperature changing rate, and sample mass on hysteresis degree. Besides, the causes of PCH were interpretated from the respective of energy storage, temperature delay, thermal resistance of PCMs, crystallinity, and interfacial free energy. The results showed that PCH phenomenon is controllable, thereby improving the energy utilization efficiency of PCMs. Namely, the prepared PA/MWCNTs/SDBS composite PCM with suitable phase transition temperature of 5.5 °C, high latent heat of 222.7 J g -1 , and thermal conductivity of 0.3727 W m -1 K -1 , possesses enormous potential in large-scale applications.

High-quality perovskite films with larger grain size and fewer defects is a prerequisite for high-performance perovskite solar cells (PSCs). Antisolvent-assisted crystallization is an effective approach to obtain compact and uniform perovskite films; however, the majority of antisolvents currently applied have strong toxicity, and the control of perovskite crystallization is not easy through single antisolvent. In this work, a green antisolvent of ethyl acetate (EA) with acetylacetone (AA) additive is used to fine-tune perovskite crystallization and passivate defect, which produces uniform and compact CH3NH3PbI3 perovskite films having larger grain and fewer grain boundaries and reduced defect density. Meanwhile, the interfacial hydrophobic characteristic of the perovskite films is enhanced. At the optimized concentration of AA in EA, the power conversion efficiency (PCE) of the CH3NH3PbI3 PSCs was improved from 19.2% to 21.1% and their stability in air was also enhanced. These results present a green antisolvent additive engineering strategy to enhance the crystallinity, passivate defects, and fabricate efficient and stable PSCs.

Introducing additives into perovskite layers is an effective method to enhance the power conversion efficiency (PCE) and operation stability of perovskite solar cells (PSCs). Herein, we reported an addition of carbon nanodots (CNDs) into the CsPbI2Br photoactive layer to boost performance of the related PSCs. It is found that the trap density can be notably suppressed, and the crystallinity can be enhanced after introducing CNDs with an optimal quantity. The PSC with 1.0 wt% addition of CNDs delivers a notable improved average PCE of 13.77% (the highest PCE: 14.69%) from that of 12.14% for the control device without CND addition. Moreover, the CND-added CsPbI2Br PSCs exhibit superior stability, i.e., ∼86 % retention of the initial PCE after 160 h aging in air with the humidity of 20%–30%, to the control device.

One type of new light-responsive hierarchical metal organic framework (MOF) has been successfully prepared using Co(NO3)3·6H2O as the metal salt and 4,4′-azobenzenedicarboxylic acid as the ligand by microwave method for the first time. It is found that MOF [Co(AzDC)] exhibits a light-responsive characteristic to SO2 adsorption due to the presence of azo group from the ligand. The light-responsive hierarchical MOFs are incorporated into Matrimid® 5218 (PI) matrix to prepare mixed matrix membranes (MMMs) for gas separation application. The morphology, crystallinity, chain mobility and thermal stability of MMMs are explored. Results show that Co(AzDC) may elevate both the CO2(SO2) permeability and CO2(SO2)/N2 selectivity of the MMMs. In particular, the Co(AzDC) doped MMMs exhibit the significantly improved CO2(SO2)/N2 selectivity from 33 (123) for PI control membrane to 78 (420) for MMMs, overcoming the 2008 Robeson upper bound for CO2/N2 system. Size-sieving effect of Co(AzDC) with pore size 0.35 ​nm enhances the selectivity, while the –N N- group from Co(AzDC) shows affinity to CO2 molecular rather than N2, also elevating selectivity of MMMs. In brief, enhanced selectivity of high-performance membrane is attributed to incorporation of Co(AzDC) particles, which displays synergistic effects both in size-sieving and CO2-philic interaction for CO2/N2 separation. Smart highly selective interface is constructed in MMMs by switching the configuration of MOFs from cis to trans. The SO2 permeability and SO2/N2 selectivity of MMMs are investigated under both visible light and ultraviolet light states, and the SO2/N2 separation performance under visible light is notably improved in comparison with that under ultraviolet light state.

Perovskite solar cells (PSCs) have become a promising photovoltaic (PV) technology. Meanwhile, developing an electron transport layer (ETL) has been an effective way to promote the power conversion efficiency (PCE) of PSCs. Here, a 4-morpholine ethane sulfonic acid sodium salt (MES Na+) doped SnO2 ETL is utilized in planar heterojunction PSCs. The results show that the MES Na+ doped ETL can improve the crystallinity, and absorbance of perovskite films, and passivate interface defects between the perovskite film and SnO2 ETL. The doping effect accounts for the enhancement of conductivity and the decreasing work function of SnO2. When 10 mg mL-1 MES Na+ was added to the SnO2 precursor solution, the device showed the best performance Jsc, Voc, and FF of the PSCs values, which were 23.88 mA cm-2, 1.12 V and 78.69%, respectively, and the PCE was increased from 17.43% to 21.05%. This doping ETL strategy provides an avenue for defect passivation to further increase the efficiency of perovskite solar cells.

To acquire efficient photocatalysts, it is necessary to make effective use of visible light/Near Infrared (NIR) light, which takes up a large percentage of sunlight. Integrating upconversion materials with visible light active photocatalysts has attracted much attention in this regard. The interface contact between upconversion material and photocatalyst has potential influence on the properties and thus the performance of the system. In this work, NaYF4:Yb,Er/CdS composites of the upconversion material NaYF4:Yb,Er nanorods and CdS nanoparticles were synthesized by ion adsorption/precipitation process and were then annealed in an argon atmosphere at different temperatures to modulate the microstructures. The annealing process endows the crystal transformation of cubic CdS with low crystallinity to hexagonal CdS with high crystallinity and, importantly, good interface contact between NaYF4:Yb,Er and CdS. Consequently, the hydrogen evolution activity greatly increases from 171 to 2539 μmol h−1 g−1 under the light irradiation of λ > 400 nm, and from 0 to 19 μmol h−1 g−1 under the light irradiation of λ > 600 nm. This work might provide a useful reference for the rational design of promising photocatalyst involving upconversion materials.

Fabrication of multifunctional nanoplatform to in situ monitor Fenton reaction is of vital importance to probe the underlying reaction process and design high-performance catalyst. Herein, a hybrid catalyst comprising of single-crystalline Au nanoparticles (SC Au NPs) on reduced graphene oxide (RGO) sheet was prepared, which not only exhibited an excellent 1O2 mediated Fenton-like catalytic activity in promoting rhodamine 6G (R6G) degradation by activating H2O2, but also displayed a sensitive surface-enhanced Raman spectroscopy (SERS) detection performance to R6G with a linear response range from 1.0 × 10−8 mol/L to 1.0 × 10−5 mol/L thus providing a powerful and versatile nanoplatform for in situ SERS monitoring Fenton-like catalytic reaction. The integration of catalytic and SERS activities into a single nanostructure are expected to provide great potentials for practical applications in environmental catalysis.

To explore the influence of TiO2 and B2O3 contents on the sintering behavior and crystallization of SrO–BaO–B2O3–SiO2 glass-ceramics, the glass-ceramics with different TiO2/B2O3 ratios were prepared by sintering at 800 and 850 °C for 10 min. The results showed that the glass transition temperature and sintering temperature increased with increasing the TiO2/B2O3 ratio. The average bridging oxygen number decreased from 2.44 to 2.07, which revealed that the polymerization degree of the glass-ceramics decreased. With increasing the TiO2/B2O3 ratio, the crystallinity of the glass-ceramics and the homogenization of grains size were improved, and the precipitation of the SrTiO3 phase was promoted. The sample with a TiO2/B2O3 ratio of 0.62, which achieved excellent densification sintered at 850 °C for 10 min, showed a dielectric constant of 18.11, a dielectric loss of 3.93 ×10−3, and a thermal expansion coefficient of 10.04×10−6 K−1, indicating that the SrO–BaO–B2O3–SiO2 glass-ceramics have great potential in the application of low-temperature cofired ceramics.

The AgCuInGa alloy precursors with different Ag concentrations are fabricated by sputtering an Ag target and a CuInGa target. The precursors are selenized in the H2Se-containing atmosphere to prepare (Ag,Cu)(In,Ga)Se2 (ACIGS) absorbers. The beneficial effects of Ag doping are demonstrated and their mechanism is explained. It is found that Ag doping significantly improves the films crystallinity. This is believed to be due to the lower melting point of chalcopyrite phase obtained by the Ag doping. This leads to a higher migration ability of the atoms that in turn promotes grain boundary migration and improves the film crystallinity. The Ga enrichment at the interface between the absorber and the back electrode is also alleviated during the selenization annealing. It is found that Ag doping within a specific range can passivate the band tail and improve the quality of the films. Therefore, carrier recombination is reduced and carrier transport is improved. The negative effects of excessive Ag are also demonstrated and their origin is revealed. Because the atomic size of Ag is different from that of Cu, for the Ag/(Ag + Cu) ratio (AAC) ≥ 0.030, lattice distortion is aggravated, and significant micro-strain appears. The atomic radius of Ag is close to those of In and Ga, so that the continued increase in AAC will give rise to the AgIn or AgGa defects. Both the structural and compositional defects degrade the quality of the absorbers and the device performance. An excellent absorber can be obtained at AAC of 0.015.

Design of high energy density lithium storage materials is one of the everlasting issues in energy storage systems to realize a fully clean and sustainable energy grid. Here, 2,9-dimethyl quinacridone was selected as a precursor to prepare carbon-based electrode via low temperature heat-treatment process from 750 °C to 1050 °C. The pyro-polymerization of 2,9-dimethyl quinacridone induced a distinctive morphological transformation from rice husk-shaped 2,9-dimethyl quinacridone to carbon nanofibers. Electrode fabricated from pigment derived carbon nanofibers (PCNF) pyrolyzed at 750 °C maintained 878 mAh g-1 at a current density of 1 A g-1 and good Coulombic efficiency up to 98% after 1000 cycles. Furthermore, it delivered 337 mAh g-1 at a high current density of 25 A g-1. The superior performance was attributed to the stable structure of pristine 2,9-dimethyl quinacridone giving high thermal stability and crystallinity owing to well-defined π-π and hydrogen bonding interactions, thus rendering a stable microstructure with a large d-spacing of (002) plane of 3.580 A, as well as efficient surface redox reactions. Density functional theory calculations indicated that the large interlayer distance could facilitate fast lithium ion insertion/extraction because of a ∼38% lower energy barrier for lithium ion insertion than compared with graphite.

Although all-inorganic perovskites possess suitable bandgap and thermal stability for photovoltaic applications, the unstable film morphologies, and poor moisture stabilities lag behind the organic-inorganic hybrid counterparts. Herein, we demonstrate that high quality α-CsPbI2Br films with improved phase stability, high crystallinity, and pinhole-free film morphology was achieved by employing tetramethylammonium chloride (TMACl) as an additive. As a result, the TMACl-added CsPbI2Br films exhibited high power conversion efficiency of 14.12% with an open-circuit voltage of 1.19 V, a short-circuit current density of 15.08 mA/cm2, and a fill factor of 0.78. More importantly, the TMACl addition imparts hydrophobicity to the film surface of CsPbI2Br, which delivered excellent stability up to 30 days in the ambient condition and thermal stability at 85 °C for 156 h, respectively. Moreover, the TMACl-added device also exhibited excellent PCE of 27.16% under indoor light source (1000 lux), which presents a promising approach for designing stable but high performance all-inorganic perovskite solar cells.

Layered double hydroxides, especially Zn-Al, are valuable matrices for intercalation with various functional anions: dyes, medicines, food additives, etc. For the purposeful development and optimization of the technology for the synthesis of Zn-Al hydroxides intercalated with functional anions, the phase composition and crystal structure of Zn-Al nitrate layered double hydroxide samples (Zn:Al=4:1) synthesized at solution flow rates of 0.8 and 1.6 l/h, pH=7, 8, 9, 10 and t=10, 20, 30, 40, 50 and 60 °С were studied. XRD showed that all samples synthesized at different temperatures, pH, and solution flow rates were Zn-Al layered double hydroxides with an α-Zn(OH)2crystal lattice of medium crystallinity, with an admixture of an oxide phase with a ZnO lattice. Three sections of the dependence of the crystallite size of the sample on the synthesis temperature were distinguished: 10–20°C, 30–50°C, and 60°C, within which an increase in temperature led to an increase in crystallinity. A hypothesis was put forward about a change in the mechanism or kinetics of LDH formation at temperatures of 30°C and 60°C. An increase in the pH of the synthesis and the flow rate of solutions led to an increase in crystallinity. A retrospective comparative analysis of the phase composition and crystal structure of Zn-Al-nitrate and Zn-Al-tripolyphosphate (tartrazine or Orange Yellow S) LDH samples was carried out. It was found that the use of large and multi-charged functional anions caused significant adsorption on precipitate nuclei and difficult intercalation. As a result, low crystallinity was formed (Tartrazine anion) or a significant part of LDH was decomposed to oxide (tripolyphosphate and Orange Yellow S anions).

Ga2O3 films were deposited on Si substrates through radio-frequency magnetron sputtering at room temperature and were annealed in situ in a high-vacuum environment. The as-deposited Ga2O3 film exhibited an island-like surface morphology and had an amorphous microstructure, with a few nanocrystalline grains embedded in it. After high-temperature in situ annealing, the films recrystallized and exhibited coalesced surfaces. Because of the thermally driven diffusion of Ga, the interfacial layer between Si and Ga2O3 was composed of SiGaOx. Compared with ex situ annealing in air, in situ annealing in high vacuum is more advantageous because it enhances surface mobility and improves the crystallinity of the Ga2O3 films. The higher oxygen vacancy concentration of in situ annealed films revealed that oxygen atoms were easily released from the Ga2O3 lattice during high-vacuum annealing. Photoluminescence (PL) spectra exhibited four emission peaks centered in ultraviolet, blue, and green regions, and the peak intensities were significantly enhanced by thermal annealing at >600 °C. This work elucidates the effect of the in situ annealing treatment on the recrystallization behavior, interfacial microstructure, oxygen vacancy concentration, and PL performance of the Ga2O3 films, making it significant and instructional for the further development of Ga2O3-based devices.

High performance acute toxic methanol sensor based on hydrothermally prepared hexagonal nanodisc (NDs) of ZnO/CdO/SnO2 (ZnCdSnO2 or ZCSO) was fabricated onto glassy carbon electrode (GCE). The characterization of ZCSO NDs in-terms of functional group analysis, binding energy evaluation, oxidation states, optical absorbance, crystallinity, structural morphology, and elemental compositions were performed by FTIR spectroscopy, X-ray photoelectron spectroscopy (XPS), UV-visible spectroscopy, XRD, FESEM-coupled-EDS analysis respectively. The current versus concentration plot was exhibited linear on a wide range of methanol concentration (0.01 nM to 0.1 mM) clarified as linear dynamic methanol detection range (LDR). Considering the ZCSO NDs-coated surface area onto GCE over the slope of LDR, noticeable methanol sensor sensitivity (4.5475 µAµM-1cm-2) was perceived. Besides this, a considerable lower limit (7.69±0.38 pM) of detection at signal/noise=3 is obtained. The overall results of methanol chemical sensor were found with satisfactory and acceptable results in terms of their reproducibility, sensitivity, stability, and response-time. Additionally, the assembled ZCSO NDs-coated electrode was validated with real environmental samples and result was found good and acceptable. On considering the outcome of applicability and the way of this sensor assembling, this unique method might be a potential technique in the field of portable sensor development for the safety of environmental and healthcare fields in a broad scale.

The obtainment of low-cost, easily prepared and high-powered LiMn2O4 is the key to achieve its wide application in various electronic devices. In this work, a mild and easily scaled molten salt method (KCl@LiCl) is utilized to convert commercial MnO2 to the high-performance LiMn2O4. At the same reaction temperature, the molten salt method leads to the formation of K+-doped LiMn2O4 with higher crystallinity compared to the conventional solid state method, which contributes to the improved inner charge transfer. The Li3PO4 protective layer is coated on the surface of K+-doped LiMn2O4 to elevate the interfacial stability and the Li+ transfer on interface. Thus, the optimized electrode shows a higher specific discharge capacity (103/60 mAh g−1 at 0.02/2 A g−1) and a longer cyclic life (80 mAh g−1 after 500 cycles at 0.5 A g−1) compared to those of LiMn2O4 by solid state method (49/2 mAh g−1 at 0.02/2 A g−1 and 20 mAh g−1 after 500 cycles at 0.5 A g−1).

Thin films of Ag–Al2O3 composites were successfully grown on Si substrate by thermal evaporation method and their thermoelectric performance was modulated using post growth annealing technique. Pellet of Ag and Al mixture having 1:4 ratio was evaporated on Si substrate using the vacuum tube furnace. As grown sample was cut into pieces and post-growth annealing was performed at different temperatures using muffle furnace. XRD results suggested that as-deposited sample has amorphous nature, but crystallinity of the samples increase as an annealing temperature increase from 600 to 900oC. This structural behavior of annealed samples was further verified by Raman spectroscopy measurements. We have reported an optimal annealing temperature (800 0C) for the best thermoelectric performance of investigated composites. At this specific annealing temperature, charge carriers are highly mobile which resulted in the enhancement of thermoelectric power generation performance of Ag–Al2O3 composite. The value of power factor (1.38x10−2 W/m-K−2) reported in the current study is the highest value for Ag–Al2O3 composites so for reported in the literature according to the best of our knowledge.

NaY2F7:Er3+,Yb3+ glass-ceramics (GC) with high transmittance were well manufactured using a melt-quenching technique and subsequent thermal treatment. Structure, morphology and photoluminescence properties of all samples were thoroughly studied via X-ray diffraction, transmission and up-conversion emission spectrum. Due to the improved crystallinity after thermal treatment, the up-conversion emission intensity of GC was significantly higher than the precursor glass. The optical thermometry performances of Er3+ ions at thermally coupled (2H11/2/4S3/2), and non-thermally coupled energy levels (2H11/2/4F9/2) were explored. Their relative sensitivities (SR) are 1.00% K−1 and 0.76% K−1 at 323 K, respectively. Moreover, their maximum temperature measurement errors (ΔT) are 0.09 K and 0.12 K at 563 K, with repeatability (R) exceeding 99% and 98%, respectively. All of the findings suggest that NaY2F7 GC are excellent self-calibration temperature measuring materials, with superior temperature resolution and repeatability.

ZnAl2O4 nanocrystalline particles were prepared using the solution combustion method using a new combustion fuel, Leucine. The prepared samples' structural, microstructural–elemental composition, and optical characteristics were investigated using XRD, SEM-EDS, and UV–Visible spectroscopy. As-synthesized ZnAl2O4 nanoparticles are polycrystalline, with no secondary phases, and crystallized in a cubic - spinel structure. The polycrystalline nature of the prepared sample is due to the exothermicity of fuel and oxidizer, which demonstrate that the fuel utilized (Leucine) provided adequate energy for the production of nanoparticles in their as-synthesized form, as supported by adiabatic temperature through thermodynamic calculations. The thermodynamic calculations also include a universal method to estimate the specific heat capacity at constant pressure. Furthermore, even after 2 h of calcination at 600 °C, ZnAl2O4 exhibits a single phase with no secondary phases, indicating the material stability and single-phase nature. The crystallinity of ZnAl2O4 nanoparticles was observed to increase with increasing annealing temperature. SEM micrographs of as-synthesized samples exhibit the formation of dense particles, voids, and pores in the as-synthesized sample. In addition, tiny aggregates were detected on the surface of more prominent clusters, which reduced as the calcination progressed. In addition, calcined samples exhibit a greater optical reflectance than as-synthesized samples. Tauc's graphs were used to compute the optical energy bandgap. The calculated energy band gap is redshifted to that of the bulk material. The bandgap energy decreases upon calcination, suggesting that the prepared materials have a larger crystallite size or more crystallinity. Correlations were found between the Tad, and the structural and optical properties of the prepared samples. The findings suggest that Leucine could be used as a novel combustion fuel to produce crystalline ZnAl2O4 nanoparticles in their as-synthesis form.

Developing effective electrocatalyst and fundamentally understanding the corresponding working mechanism are both urgently desired to overcome the current challenges facing lithium-oxygen batteries (LOBs). Herein, a series of NiFe-based bimetal-organic frameworks (NiFe-MOFs) with certain internal tensile strain are fabricated via a simple organic linker scission strategy, and served as cathode catalysts for LOBs. The introduced tensile strain broadens the inherent interatomic distances, leading to an upshifted d-band center of metallic sites and thus the enhancement of the adsorption strength of catalysts surface towards intermediates, which is contributed to rationally regulate the crystallinity of discharge product Li2O2. As a result, the uniformly distributed amorphous film-like Li2O2 tightly deposits on the surface of strain-regulated MOF, resulting in excellent electrochemical performance of LOBs, including a large discharge capacity of 12317.4 mAh g−1 at 100 mA g−1 and extended long-term cyclability of 357 cycles. This work presents a novel insight in adjusting the adsorption strength of cathode catalysts towards intermediates via introducing tensile strain in catalysts, which is a pragmatic strategy for improving the performance of LOBs.

Polymer-based thermally conductive composites have attracted tremendous interest in thermal management of electronics. However, it remains challenging to achieve high thermal conductivity partly because the difficulty to obtain favorable distribution and orientation of conductive fillers within the polymer matrix. Herein, networked boron nitride (BN) conductive pathway was realized within the poly (lactic acid) (PLA) matrix, via regenerated cellulose (RC)-assisted assembly of BN on Pickering emulsion interface based on the noncovalent interaction, followed by solvent evaporation and hot-compressing. The strong noncovalent interactions between BN and RC were found critical to enhance the wettability and stability of BN in aqueous media with a lowest mass ratio of 1:40 of RC and BN. The obtained PLA/BN composites feature a thermal conductivity of 1.06 W/mK at 28.4 wt% BN loading, representing an enhancement of 430% comparing to neat PLA, and the crystallinity of the composites could increase significantly from 11.7% (neat PLA) to 43.7%. This simple, environmentally friendly and effective strategy could be easily extended for effective construction of thermally conductive composites.

SrLi2Ti6O14 (SLTO) coated with different amount of ZrO2 was successfully prepared. The as-obtained composites are stacked by a series of particles with a pure phase structure and a good crystallinity. Furthermore, ZrO2 coating not only enhances the structural stability of the materials but also facilitates the diffusion of lithium through the SEI film. As a result, the redox polarization was reduced, and the reversibility of the electrochemical reaction was enhanced. Particularly, SLTO-ZrO2-2 sample delivers a high initial lithiation capacity of 283.6 mA h g−1, and the values maintain at 251.7, 228.0, 207.4, 175.3, and 147.7 mA h g−1 at the current densities of 0.13, 0.26, 0.54, 1.31, and 2.62 A g−1, respectively. Our experiment also confirmed that SLTO materials coated with ZrO2 are suitable for high power density applications, and the lithiation specific energy efficiency of SLTO-ZrO2-2 is 200% as high as that of pure SLTO at a power density of 1257 W kg−1.