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Biopolymer electrolytes based on iota-carrageenan (I-carrageenan) with sodium trifluoromethanesulfonate (NaTf) were prepared by way of the conventional solution-casting technique. The biopolymer I-carrageenan was fixed as 1 g, and the concentration of NaTf was varied from 0.1 to 0.5 wt% in steps of 0.1 wt%. Distilled water was used as a solvent. Alternating current (AC) impedance measurements were carried out in the frequency window of 42 Hz–1 MHz. The same measurements were also carried out at different temperatures for all the prepared biopolymer samples. A maximum ionic conductivity of 2.6771 × 10−5 S/cm was obtained for the 0.3 wt% NaTf-added I-carrageenan system at room temperature. The temperature-dependent conductivity plot of the polymer electrolyte seemed to obey the Arrhenius relation. A low activation energy of 0.021 eV was observed for the sample with the highest ionic conductivity. From AC impedance data, dielectric parameters were obtained. The magnitude of the dielectric constant was found to increase with the increase in temperature. A low relaxation time was observed for the sample that possesses the maximum ionic conductivity.

In the present work, samples of barium borate glasses containing different molar ratios of ZnO were prepared using the conventional melt-quenching technique. X-ray diffraction studies confirmed the amorphous nature of the studied materials. Structural analysis using FT-Infrared confirmed the incorporation of the Zn atom in the glass matrix as a ZnO4 unit and the existence of ZnO in the tetrahedral interstitial sites. TEM images for the studied materials show that the average particle size is about 20 nm and the ZnO4 structural units reside in the glass matrix with high homogeneity. Density and molar volume studies manifested an increase in the density as the amount of ZnO increases and a subsequent decrease in the molar volume. UV absorption studies showed a blue shift in the absorption peak from 343 nm to 315 nm. Additionally, an observed reversible behavior around 338 nm divides the absorption range into high energy and low energy regions. In the high energy region, both absorbance, absorption coefficient, and refractive index increased with ZnO content increment. In the low energy region, this behavior was reversed, and the calculated values of the refractive index agreed with the measured ones in this region. Studies of optical dielectric parameters showed a Debye-type relaxation process in which increasing the ZnO content shortens the sample relaxation time. Our results, collectively, suggest the studied materials for several optoelectronic device applications such as high-energy optical filters, optical switches, and frequency converters.

The development of greatly stable and cost-effective electrocatalysts for urea electro-oxidation reactions (UERs) is urgent and challenging for promoting urea removal in the wastewater and advanced energy conversion devices. We demonstrated that nickel-iron borate (NiFe-B) electrocatalysts supported on carbon paper (CP) for UERs through a one-pot solvothermal method. NiFe-B electrocatalysts were obtained with numerous Ni/Fe molar ratios in the precursors, and the physicochemical features of the NiFe-B were examined by X-ray diffraction, scanning and transmission electron microscope, and X-ray photoelectron spectroscopy. The optimized NiFe-B/CP exhibited a low onset potential (Eonset = 0.287 V vs. SCE) with a Tafel slope of 27.9 mV/dec on CP, demonstrating much greater performance UERs. Furthermore, the NiFe-B/CP catalysts have shown a superior activity for the UERs in alkaline solution and exhibit more than two-fold enhancement in activity than Ni-B. Facile, cost-effective fabrication and highly efficient urea oxidation create the NiFe-B electrodes as attractive materials for UERs.

The ever-increasing demands for modern energy storage applications drive the search for novel anode materials of lithium (Li)-ion batteries (LIBs) with high storage capacity and long cycle life, to outperform the conventional LIBs anode materials. Hence, we report amorphous ternary phosphorus chalcogenide (a-P4SSe2) as an anode material with high performance for LIBs. Synthesized via the mechanochemistry method, the a-P4SSe2 compound is endowed with amorphous feature and offers excellent cycling stability (over 1500 mA h g−1 capacity after 425 cycles at 0.3 A g−1), owing to the advantages of isotropic nature and synergistic effect of multielement forming Li-ion conductors during battery operation. Furthermore, as confirmed by ex situ X-ray diffraction (XRD) and transmission electron microscope (TEM), the a-P4SSe2 anode material has a reversible and multistage Li-storage mechanism, which is extremely beneficial to long cycle life for batteries. Moreover, the autogenous intermediate electrochemical products with fast ionic conductivity can facilitate Li-ion diffusion effectively. Thus, the a-P4SSe2 electrode delivers excellent rate capability (730 mA h g−1 capacity at 3 A g−1). Through in situ electrochemical impedance spectra (EIS) measurements, it can be revealed that the resistances of charge transfer (Rct) and solid electrolyte interphase (RSEI) decrease along with the formation of Li-ion conductors whilst the ohmic resistance (RΩ) remains unchanged during the whole electrochemical process, thus resulting in rapid reaction kinetics and stable electrode to obtain excellent rate performance and cycling ability for LIBs. Moreover, the formation mechanism and electrochemical superiority of the a-P4SSe2 phase, and its expansion to P4S3−xSex (x = 0, 1, 2, 3) family can prove its significance for LIBs.

Metallic glasses have recently attracted great attention in terms of degrading dyes and other organic pollutants as an environmentally friendly material for wastewater remediation. Herein, we report a new type of amorphous catalyst Fe41Co7Cr15Mo14C15B6Y2 hollow balls. Results demonstrate that the catalyst can still completely decolorized the 20 mg/L methylene blue (MB) solution after reused for 50 times under conditions of pH = 5, catalyst content 0.5 g/L, and temperature 80 °C. The catalyst is easily broken during degradation, so the inner surface also provides additional active sites. The Fe41Co7Cr15Mo14C15B6Y2 amorphous alloy hollow balls were characterized by EDS, SEM and XPS, respectively. The elements in the catalytic system have a synergistic catalytic effect. Redox cycle Fe2+/Fe3+, Co2+/Co3+ and Mo4+/Mo6+ promote mutual conversion and accelerate the catalytic process of their reaction with H2O2, forming a self-stable redox cycle process. Among them, Fe2+ promotes the conversion of Co3+ to Co2+, and Mo4+ promotes the conversion of Fe3+ to Fe2+, mainly Fe2+ and Co2+ react with H2O2 to generate •OH. Mo and Cr element form MoO2 and Cr2O3 plasma compounds on the surface, which act as a protective film to make the catalyst more stable and repeated use more frequently.

Adsorption is a simple and efficient phosphorus removal method used to control the eutrophication of water bodies. A simple and gentle atmospheric pressure hydrothermal method by adjusting the dosage of ammonium chloride and sodium hydroxide was used to synthesize amorphous, monoclinic, and tetragonal zirconia nano-powders with high specific surface areas (383.91 m2/g, 330.01 m2/g, and 234.36 m2/g) and particle size of about 40 nm for phosphate adsorption. When pH = 6.3, the phosphate adsorption capacity of the amorphous monoclinic phase and the tetragonal phase respectively reached 102.58 mg P/g, 68.11 mg P/g, and 37.25 mg P/g and the adsorption process of the three crystal forms of zirconia powders conformed to the Langmuir adsorption model. In the first 2 min of rapid adsorption, amorphous zirconia completed 76.23% of the adsorption process and the monoclinic phase also completed more than 60%. The adsorption process of the three crystal forms of zirconia was completed within 240 min and conformed to the pseudo-second-order kinetic model. Their adsorption characteristics of the three crystal forms of zirconia decreased with the increase in pH. While the pH was above than the isoelectric point of the solution, the adsorption capacity was significantly reduced. The large specific surface area and high hydroxyl content of the zirconia nano-powder made a great contribution to the adsorption process.

Carbon aerogels with nanoporous structure are attractive for thermal insulation under extreme conditions, but their practical applications are usually plagued by the inherent brittleness and easy-oxidation characteristic at high temperature. Herein, silica-modified carbon aerogels (SCAs) with extraordinarily high strength are prepared via a facile sol-gel polymerization of phenolic resin and siloxane, followed by ambient pressure drying and carbonization. The resulting SCAs possess medium-high density of ∼ 0.5 g·cm-3 and mesoporous structure with the mean pore size of 33 nm. During carbonization process, the siloxane could be gradually transformed into the amorphous SiO2 particles and crystalline SiC particles, which are coated on the surface of carbon nanoparticle and consequently improve the oxidation-resistance of carbon aerogels. Due to the density-porosity trade-off, the SCAs have high compressive strength of 10.0 MPa and satisfied thermal conductivities of 0.118 W·m-1·K-1 at 25 °C and 0.263 W·m-1·K-1 at 1000 °C. Furthermore, needled carbon fiber-reinforced SCAs (CF-SCAs) with ultrahigh compressive strength of 210.5 MPa are prepared, which exhibit good thermal conductivities of 0.207 W·m-1·K-1 at 25 °C and 0.407 W·m-1·K-1 at 1000 °C. The ultrahigh mechanical strength, good oxidation-resistance, good thermal insulation as well as the facile preparation make the SACs great promising in high-temperature insulations especially under harsh conditions.

Development of electrocatalyst using facile way from non-noble metal compounds with high efficiency for effective water electrolysis is highly demanding for production of hydrogen energy. Nickel based electrocatalysts were currently developed for electrochemical water oxidation in alkaline pH. Herein, amorphous nickel tungstate (NiWO4) was synthesized using the facile successive ionic layer adsorption and reaction method. The films were characterized by X-ray diffraction, Raman spectroscopy, Fourier transfer infrared spectroscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy techniques. The electrochemical analysis showed 315 mV of overpotential at 100 mA cm−2 with lowest Tafel slope of 32 mV dec−1 for oxygen evolution reaction (OER) making films of NiWO4 compatible towards electrocatalysis of water in alkaline media. The chronopotentiometry measurements at 100 mA cm−2 over 24 h showed 97% retention of OER activity. The electrochemical active surface area (ECSA) of NW120 film was 25.5 cm−2.

International audience; In order to understand the nature of the dust that accreted onto chondrules in the nebula and to unravel the conditions of formation of fine grained rims (FGRs), we studied three of the least altered chondrites from different chondrite groups (LL3.00 Semarkona, CO3.0 DOM 08006, CR2.8 QUE 99177) and compared the results with our previous work on the Paris CM chondrite (Zanetta et al., 2021). For each sample, we selected representative rimmed chondrules showing minimal traces of aqueous alteration. We performed high-resolution SEM X-ray chemical mapping to obtain relevant phase abundances and grain size distributions. Four FIB sections were then extracted from each meteorite, two in the rims and two in their adjacent matrix for quantitative TEM analysis. At the microscale, texture, modal abundances and grain size differ depending on the chondrite but also between FGRs and their adjacent matrix. At the nanoscale (i.e. TEM observations), matrices of the four chondrites consist mostly of domains of amorphous silicate associated with Fe-sulfides, Fe-Ni metal, Mg-rich anhydrous silicates and an abundant porosity. The related FGRs in Semarkona (LL) and DOM 08006 (CO) exhibit more compact textures with a lower porosity while FGRs in QUE99177 (CR) are similar to the matrix in terms of porosity. In the three chondrites, FGRs are made of smooth and chemically homogeneous amorphous (or nanocrystalline) silicate with no porosity that encloses domains of porous amorphous silicate bearing Mg-rich anhydrous silicates, Fe-sulfides, Fe-oxides and sometimes metal and Fe-rich olivines. The average compositions in major elements of the amorphous regions are similar for the FGRs and the matrix within a given chondrite (but differ between chondrites). The texture and the chemical homogeneity of the smooth silicate and the fact that it encloses domains of porous amorphous silicate bearing other mineral phases similar to matrix-like material suggests a formation by condensation. Areas that are enclosed in this smooth silicate exhibit Fe-rich olivine formed through Fe interdiffusion that also suggest a thermal modification of the dust accreted to form FGRs. These characteristics indicate a transformation process for the modification of the FGR material similar to the one proposed in our previous work on Paris. We conclude that matrix and FGRs accreted a similar type of dust but FGR material was affected by thermal modification and compaction contemporary with their accretion. For each chondrite, dust accreted onto chondrules under different conditions (dust density, temperature) which led to diverse degrees of compaction/thermal modification of the sub-domains and explain the textural differences observed in FGRs. They accreted on chondrules in a warm environment related to the chondrule formation episode, whereas matrix accreted later in a cooler environment.

In this paper, the crystallization behavior of a novel poly(monothiocarbonate), poly(trimethylene monothiocarbonate) (PTMMTC), was investigated and compared with its polycarbonate analogue, poly(trimethylene carbonate) (PTMC). It is found that PTMMTC exhibits strong crystallizability, while unstretched PTMC is amorphous. DSC and DMA results reveal that PTMMTC possesses higher glass transition temperature (Tg) and β-transition temperature (Tβ) than PTMC. Simulation based on density functional theory (DFT) shows that, the bond angle of C-S-C is evidently smaller than that of C-O-C, and thus a larger dipole moment. This leads to the stronger intermolecular interaction and more rigid chain conformation in PTMMTC, which is the origin of sulfur-substitution enhanced crystallization. The crystal structure of PTMMTC was preliminarily determined for the first time. PTMMTC has an orthorhombic crystal structure with a planar zig-zag chain conformation. The parameters of unit cell are a = 10.74 A, b = 4.79 A, and c (fiber axis) = 7.74 A.

Herein, we investigate silicate-phosphate glasses from the SiO2–P2O5–K2O–MgO–SO3 system enriched with various amounts of sulfur, as a nutrient indispensable for the proper development of plants, in order to gain a profound understanding of the structure of such materials. An inherent capability of glasses from the studied system to incorporate sulfate groups into the vitreous matrix was discussed on the basics of the results from XRF, XRD and internal Al2O3 standard techniques. It has been found, that as much as 3 mol.% of SO3 can be loaded into the glass batches to obtain fully amorphous material, while beyond this limit K2SO4 crystallizes within the matrix. Comprehensive spectroscopic investigation, comprising Raman, Middle Infrared (MIR), 29Si and 31P MAS-NMR, X-ray absorption spectroscopy (XANES and XAS) techniques, has been implemented in order to determine an impact of sulfur on silicate-phosphate glass framework. On this basics, it has been concluded, that sulfur exists in the vitreous matrix in the form of specific domains, in which [SO4]2- anions are surrounded by the shell of charge-compensating K+ cations. Such sulfate groupings maintain their individuality without direct bonding to silico-oxygen or phospho-oxygen subnetwork. Spectroscopic results revealed also, that the presence of sulfur affects silico-oxygen subnetwork to a significantly greater extent than the phospho-oxygen one. It has been demonstrated, that along with SO3 addition, the more polymerized Q S i 3 units increase in abundance at the expense of less polymerized Q S i 2 groups. Results of the present study are believed to contribute to a greater understanding of the nature of sulfur-bearing oxide glasses.

Transition-metal-based nitrides and carbides have been widely studied for various applications because of their excellent mechanical, electrical, and catalytic properties. Although outstanding performances of Mo nitride and carbonitride synthesized by chemical reaction methods have been reported recently for catalytic applications, a metallic phase transition method for pre-deposited MoO3 precursor films, which is suitable for application to Si or metallic substrates, has rarely been reported. Herein, we investigate Mo nitride and carbonitride thin films synthesized via nitriding and carbonitriding of MoO3 films using two types of ammonium salt precursors, urea and ammonium carbonate (AC), in the chemical vapor deposition (CVD) process. The phase-changed crystalline films of Mo carbonitride via the urea reaction and Mo nitride via the AC reaction were determined to be MoC0.5N0.5 and MoN by X-ray diffractometry, respectively. Nevertheless, amorphous states of carbons and their related compounds, unreacted residual MoO3, and incompletely reacted MoO2 remained in the films, as determined by other thin film analyses. When the residual MoO2 was minimal, the films exhibited the lowest electrical resistivity, i.e., ∼10−4 Ω·cm for Mo carbonitride and ∼10−3 Ω·cm for Mo nitride, implying an optimum metallic phase transition. Our results pave the way for the nitriding and carbonitriding of transition metal oxides using ammonium salt precursors for a one-step reaction in the CVD process.

A liquid carbon-rich SiAlCN precursor is facilely synthetized by hydrosilylation between liquid polyaluminocarbosilane (LPACS) and 1,3,5,7-tetravinyl- 1,3,5,7-tetramethylcyclotetrasilazane {[CH3(CH2 CH2)SiNH]4} (TeVSZ). The structural evolution during the polymer-ceramic conversion process is investigated by various methods. The results show that the main cured mechanism is β-addition on hydrosilylation, although α-addition on hydrosilylation, polymerization of vinyl groups and dehydrocoupling reaction between N–H bonds also occur during the cured process. During the pyrolysis process, dehydrogenation and dehydrocarbonation condensation reactions, transamination reactions occur, leading to formation of a three-dimensional network inorganic structure at 400–800 °C, where part of Al–O bonds convert to Al–N bonds. Then the network inorganic structure undergoes demixing and separation into amorphous SiAlCN(O) phase, where the amorphous turbostratic free carbon phase also form at 800–1200 °C. With demixing and decomposition of the amorphous carbon-rich SiAlCN(O) phase, the crystalline β-SiC and graphitic carbon start to form at about 1400 °C, the crystalline sizes of them both enlarge with increasing temperature. However, the crystal growth of β-SiC is distinctly inhibited due to existence of the rich carbon phase, tiny amounts of Al2O3 and AlN. In addition, a small amount of AlN can promote the formation of α-SiC at 1800 °C.

Arsenic (As) contamination poses an urgent environmental risk, and its removal from groundwater remains a challenge due to the lack of efficient adsorbents. Herein, a novel granular chitosan-titanium (CS-Ti) adsorbent was fabricated by the sol-gel method. Batch experiments show that As(V) adsorption on CS-Ti followed the pseudo-second-order kinetic model, and the adsorption isotherm conformed to the Freundlich model with the correlation coefficient of 0.99. In situ FTIR spectra revealed that the CS-Ti adsorbent was composed of amorphous TiOx and chitosan by forming C-O-Ti and N-Ti bonds, and the amorphous TiOx was responsible for As(V) adsorption. Rapid small-scale column tests show that 165.6 μg/L of As in groundwater were effectively removed in approximately 126-bed volumes, and the spent adsorbents were regenerated with 0.01 mol/L NaOH and maintained the adsorption efficiency after four cycles. This study provides a simple and practical route to fabricate adsorbents for water treatment.

Amorphous catalysts, thanks to their uniquely coordinated unsaturated properties and abundance of defect sites, tend to possess higher activity and selectivity than their crystalline counterparts. ...

The preparation of amorphous pure organic room-temperature phosphorescence materials with high efficiency is still a challenging task. Herein, we introduce a CB[6] derivative-based supramolecular self-assembling strategy. A water soluble and ellipsoidal deformed CB[6] derivative is used to self-assemble with 4-(4-bromophenyl)-1-methylpyridin-1-ium chloride, bromide and hexafluorophosphate in water. After freeze-drying, the obtained amorphous complexes exhibit brilliant green phosphorescence emission under ambient conditions, with phosphorescence efficiency up to 59, 60 and 72%, respectively. This is the first report of amorphous non-polymeric pure organic room-temperature phosphorescence with such a high efficiency. In view of the dynamic self-assembling property, the complexes are responsive to water, which could enable information encryption.

The macromolecular architecture is the crucial factor in determining the arrangement of the ordering structures, which because of the multiscale feature may exhibit distinct melting behaviors and induces the so-called memory effect to affect the following recrystallization. Until present, the correlation between the occurrence of memory effect and the intrinsic molecular structure is still far from the comprehensive understanding. In this work, four kinds of 1-butene/α-olefin random copolymers were designed and synthesized using the (pyridyl-amino) hafnium catalyst to introduce the different branches. The branch length was precisely controlled by the specific α-olefin comonomers, which include 1-hexene, 1-decene, 1-tetradecene, and 1-octadecene, while the branch density was tuned by the incorporation. As expected, the incorporation of α-olefin co-units to poly(1-butene) backbone decreases the non-isothermal crystallization kinetics and the degree of crystallinity. More interestingly, the resulting linear branch is able to induce the occurrence of memory effect and the threshold concentration of co-units (i.e., branch density) decreases with increasing the branch length. Based on the results of these 1-butene/α-olefin copolymers with designable branches, a direct correlation with the occurrence of memory effect and the fraction of amorphous region was established, which quantitatively indicates the degree of local segregation of the crystallized poly(1-butene) sequences by the α-olefin co-units.

Solid polymer electrolytes (SPEs) are key materials in safety and flexibility of rechargeable lithium-ion batteries but their ionic conductivities are very low compared with that of liquid electrolytes. One of the reasons for the low ionic conductivity was the low ion dissociation due to low dielectric constant of polymer. So, it should be required to increase the dielectric constant of polymer matrix. We prepared poly (ethylene oxide) (PEO)-based composite polymer electrolyte incorporated with tetracyanoethylene (TCNE) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). Compare with dielectric constant of pure PEO (k = 5), TCNE has high dielectric constant (k ≈ 148). The dielectric constant of polymer matrix increased to 50.83 by the incorporation TCNE into PEO. Hence, incorporating LiTFSI into PEO12-TCNE complex, the ion dissociation fraction was also increased from 42.61% to 77.88%. The DSC results showed that the melting temperature (Tm) shifted to low temperature region and glass transition temperature (Tg) also decreased. After incorporation of tetracyanoethylene, the maximum ionic conductivity was obtained as 1.11 × 10−4 S/cm at room temperature.

Summary Objectives Lumefantrine, an antimalarial drug, is having poor solubility and variable bioavailability. This work is aimed to prepare and evaluate co-precipitate of lumefantrine-Eudragit E PO to improve its dissolution by anti-solvent precipitation. Material and methods The anti-solvent precipitation technique was used to prepare co-precipitate of lumefantrine-Eudragit E PO at different ratios and based on their solubility; the optimized ratio (1:0.5) was further evaluated for solid state characterization, dissolution and compared with lumefantrine and pure precipitated lumefantrine. Results The optimized ratio of co-precipitate (1:0.5) was further evaluated which showed a substantial rise in drug solubility of lumefantrine. SEM photographs indicated dispersion of drug in polymer matrix however, no interaction was observed in FTIR studies. Their DSC and XRPD data revealed the conversion of lumefantrine to its amorphous form. Further, a significant improvement in the rate of dissolution was demonstrated by co-precipitate as compare to pure drug or solely precipitated drug. This may be attributed to the partial conversion of lumefantrine in amorphous form and solubilizing capacity of Eudragit E PO. Conclusion Thus, co-precipitate of lumefantrine-Eudragit E PO was found to be useful in dissolution improvement and can be further studied for stabilization of co-precipitates.

Hydrothermal carbonization of paunch waste, the main wet waste generated at abattoirs, was investigated in batch mode. A mass loss of 58% was achieved at 240 °C in a flash experiment, whereas prolonging the reaction to 4 h increased it to 79%, indicating the ability of a hydrothermal medium for managing this wet waste. XRD analysis suggested that the amorphous portion of paunch waste was readily hydrolysed, whereas crystalline cellulose I was retained. Longer holding time partially destroyed the formed porous structure and halved the BET surface area from 68.1 to 37 m2 g-1. Aromatic, cyclic, and phenolic compounds were found in light bio-oil, while heavy bio-oil contained long-chain fatty acids derivatives. A reaction network was suggested containing 12 reaction pathways during the process, and lumped kinetic modelling was performed reasonably accurately. The techno-economic analysis also revealed that with a solids content of 3 wt.%, only processing time as short as 5 min can promise a positive net present value of $8.3 million, while longer residence times led to negative values.

To develop high-performance non-precious metal-based electrocatalysts for oxygen reduction reaction (ORR) is an urgent demand. We herein report an ingenious strategy to develop highly selective and competitive precious metal-free ORR electrocatalyst Co/CoO/SnO encapsulated in N-rich mesoporous carbon (CCS@NPC) nanocubes, via a simple one-step introduction of all functional components. Atomically mixed composites with significantly enhanced catalytic activity were obtained by adopting amorphous mesoporous ternary metal oxides CoSnO3 nanocubes as precursor and template. The synergistic effect of the triphase nanohybrids (Co, CoO & SnO) anchored in nitrogen-doped mesoporous carbon nanocubes promoted the catalytic reactions, owning to the anisotropic morphology, great heterojunction interfaces, and structural stability. The large-scale prepared CCS@NPC exhibited excellent electrocatalytic activity toward ORR with an admirable onset potential (1.01 V) and diffusion-limited current density (5.88 mA cm−2). The CCS@NPC showed stronger stability (20 h) and higher methanol tolerance with the concentration up to 8.0 M, compared to that of commercial Pt/C.

In this study, the forms of occurrence of impurity elements in silicon carbide (SiC) with different particle sizes were systematically investigated using a combination of X-ray diffraction (XRD), inductively coupled plasma-atomic emission spectrometry (ICP-OES), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The experimental results showed that in SiC powders prepared using the Acheson process, the contents of O, free-Si, free-C, and Fe impurities are high, and those of other trace impurity elements follow the order: Ti > Al > Ni > V. Moreover, O impurities mainly cover the SiC particle surface in the form of amorphous SiO2. Fe impurities exist around SiC particles as Fe2O3, FexSiy, FexSiyTiz, and FexAlySiz phases. Impurity elements are often introduced during the smelting of SiC and/or during milling or subsequent storage.

High-entropy materials (HEMs) have attracted extensive interests in exploring multicomponent systems for highly efficient and durable catalysts. Tuning composition and configuration of HEMs provides untapped opportunities for accessing better catalytic performance. Herein, we report three amorphous high-entropy transition metal oxides catalysts with uniform composition through a simple and controllable liquid phase non-equilibrium reduction method. The self-made catalyst FeCoNiMnBOx exhibits excellent oxygen evolution performance, including a low overpotential (266 mV at 10 mA cm−2), small Tafel slope (64.5 mV dec-1) and extremely high stability (only 3.71% increase of potential after 100 h test and no current decay after cyclic voltammetry of 31,000 cycles). The outstanding performance can be attributed to the in-situ electrochemical activation induced surface reconstruction to form a stable oxyhydroxide surface layer, the cocktail effect (multi-metal synergy) brought by high entropy, and the advantages of amorphous structure itself. The outstanding catalytic properties of the new high-entropy amorphous metal oxide, as well as its advantages of low cost and simple preparation, suggest its great potential in water splitting.

Improving fracture toughness, which has gone through decades, is a long-standing topic and is particularly important for safety-critical applications. In refractory transition metal carbides (RTMCs), remarkable toughening is usually achieved by adding metallic binders, however, resulting in a drastic deterioration of hardness and thermal stability. Here, we report a novel self-toughening strategy for synthesizing high-toughness RTMCs. Using mechanical alloying (MA) and spark plasma sintering (SPS), we synthesized nonstoichiometric VC1-x (0.5 ≤ 1-x ≤ 0.6) with a quasi-monophasic microstructure containing a carbon-rich matrix and carbon-poor precipitates. Significantly, the VC0.5 sintered at 1400°C shows a good trade-off of high hardness of 20.5±0.5 GPa and fracture toughness of 7.1±0.2 MPa m1/2. The fracture toughness of VC0.5 increases by more than 100% accompanied by 7% hardness loss, compared with that of stoichiometric VC. The microstructure characterization and fracture behavior analysis demonstrate that the extraordinary toughening enhancement is attributed to a self-toughening strategy combined with coherency toughening and amorphous bridging toughening, which may offer an efficient pathway for developing high-performance structural ceramics.

The polymer electrolytes are used in energy storage devices. Sodium ion-conducting gel polymer electrolytes based on Polyacrylonitrile (PAN) complexed with an alkali salt (NaI) and Ethylene carbonate (EC) and Dimethylformamide (DMF) as plasticizing solvents were prepared from solution cast method. The developed membrane were dimensionally stable. Structural, Impedance and conductivity studies were carried on to the prepared samples. The electrical studies were performed using lab-made conductivity setup. The complex formation between NaI salt and PAN had been confirmed by XRD studies and revealed the amorphous behaviour of the prepared membranes. The conductivity and bulk resistance of gel polymer electrolytes were measured by impedance analysis by changing the composition concentration of PAN-NaI. The maximum conductivity (1x10-3 S/cm) was observed for PAN: NaI (70:30) at temperature 373 K. The conductivity dependence temperature of these mebranes obeys the principle of Arrhenius.

We have developed an efficient strategy to synthesize an active and durable electrocatalyst of Pd hydride nanocubes (NCs). Instead of the traditional chemical method, the PdH0.43 NCs are firstly prepared via a hydrogen diffusion procedure, followed by hydrothermal synthesis of an amorphous CuO layer encapsulating the PdH0.43 NCs to prevent the hydrogen atoms from escaping. Obvious lattice expansion is demonstrated playing a pivotal role in the enhancement of their oxygen reduction reaction (ORR) activity and durability. The obtained PdH0.43@CuO NCs catalysts exhibit an ORR mass activity of 0.18 A mg−1 at 0.90 V versus reversible hydrogen electrode in an alkaline medium, which is about five times higher than that of commercial Pt/C. Accelerated durability tests show that there is only a 32 mV decay in half-wave potential even after 10,000 potential cycles, indicating the excellent stability of PdH0.43@CuO NCs. Density functional theory (DFT) calculations also indicate that, compared to Pd, PdH0.43 has a lower limiting barrier to form OH− during the ORR process. The present study illustrates the importance of lattice expansion caused by hydrogen and offers an available strategy to design highly efficient and durable Pd-based electrocatalysts for alkaline fuel cells.

In this work, the use of ruthenium tetroxide (RuO4) as a co-reactant for atomic layer deposition (ALD) is reported. The role of RuO4 as a co-reactant is twofold: it acts both as an oxidizing agent and as a Ru source. It is demonstrated that ALD of a ternary Ru-containing metal oxide (i.e. a metal ruthenate) can be achieved by combining a metalorganic precursor with RuO4 in a two-step process. RuO4 is proposed to combust the organic ligands of the adsorbed precursor molecules while also binding RuO2 to the surface. As a proof of concept two metal ruthenate processes are developed: one for aluminum ruthenate, by combining trimethylaluminum (TMA) with RuO4; and one for platinum ruthenate, by combining MeCpPtMe3 with RuO4. Both processes exhibit self-limiting surface reactions and linear growth as a function of the number of ALD cycles. The observed saturated growth rates are relatively high compared to what is usually the case for ALD. At 100 degrees C sample temperature, growth rates of 0.86 nm per cycle and 0.52 nm per cycle are observed for the aluminum and platinum ruthenate processes, respectively. The TMA/RuO4 process results in a 1 : 1 Al to Ru ratio, while the MeCpPtMe3/RuO4 process yields a highly Ru-rich composition with respect to Pt. Carbon, hydrogen and fluorine impurities are present in the thin films with different relative amounts for the two investigated processes. For both processes, the as-deposited films are amorphous.

The advanced process of recovering the trapped oil from the reservoir is known as Enhanced Oil Recovery (EOR), which involves the injection of foreign fluids to manipulate the reservoir’s petrophysical properties. Nanoparticles in this regard have shown significant effects on various EOR parameters, such as interfacial tension and sweep efficiency. However, the composites of different nanoparticles have been reported to have shown exceptional effects over bare single nanoparticles (NPs) because of the synergy actions concerning measures of improving their rheological properties. In this work, Zinc oxide/Silicon dioxide (ZnO/SiO2) nanocomposites were synthesized via a Sol-gel method and annealed at different temperatures (400 and 600°C). The chemical interaction, crystal structures, morphology, and composite formation were studied via Fourier-Transform Infrared Spectroscopy (FTIR), X-Ray diffractometer (XRD), Field Emission Scanning Electron Microscopy (FESEM), and Energy dispersed X-ray (EDX) respectively. The result shows that the chemical interactions between the ZnO and amorphous SiO2 were confirmed by the presence of the characteristic functional group bands, and the establishment of the chemical bond in Zn–O, and Si–O on the surface of the composite materials. From the XRD analyses, the crystal size of the ZnO/SiO2 composite materials significantly increased with an increase in temperature whereas the morphological size undergoes a reduction by increasing temperature as shown by FESEM. The rheological property (viscosity) of the ZnO/SiO2 nanocomposites was investigated and the outcome has revealed that the viscosity of the composite material increases with an increase in annealing temperature which consequently could serve as a basis to overcome the viscous fingering and facilitates the oil displacements in EOR.

Amorphous tungsten (VI) trioxide thin films were deposited on rigid Ni-foam and flexible PET substrates using RF magnetron sputtering technique. The impacts of sputtering RF power on microstructure, morphology, compositional and electrochemical properties of the deposited thin films were investigated by using Raman, FE-SEM, XPS and electrochemical techniques. The thicknesses of the deposited films were increased from 70 to 105 μm as a function of RF power. The films contain uniform nanoparticles and the observed sizes are in the range of 25–70 nm. The films of WO3@Ni and WO3@PET deposited at an optimum RF power of 100 W exhibited the high areal capacitance of 22.01 mF/cm2 and 9.76 mF/cm2 with good cyclic retention of 81.03% and 69.53% after 5000 cycles respectively. Further, two solid-state symmetric supercapacitor (SSC) devices were assembled which shows pseudocapacitive behaviour. The devices delivered moderate energy densities of 0.48 μWh/cm2 and 0.20 μWh/cm2 and power densities of 312 μW/cm2 and 150 μW/cm2 for rigid Ni foam and flexible PET based devices respectively. This result demonstrated that the binder free in-situ deposition of WO3 films deposited at an optimum RF power of 100 W is more suitable to fabricate supercapacitor devices.

Lithium–sulfur (Li–S) battery is highly regarded as a promising next-generation energy storage device but suffers from sluggish sulfur redox kinetics. Probing the behavior and mechanism of the sulfur species on electrocatalytic surface is the first step to rationally introduce polysulfide electrocatalysts for kinetic promotion in a working battery. Herein, crystalline lithium sulfide (Li2S) is exclusively observed on electrocatalytic surface with uniform spherical morphology while Li2S on non-electrocatalytic surface is amorphous and irregular. Further characterization indicates the crystalline Li2S preferentially participates in the discharge/charge process to render reduced interfacial resistance, high sulfur utilization, and activated sulfur redox reactions. Consequently, crystalline Li2S is proposed with thermodynamic and kinetic advantages to rationalize the superior performances of Li–S batteries. The evolution of solid Li2S on electrocatalytic surface not only addresses the polysulfide electrocatalysis strategy, but also inspires further investigation into the chemistry of energy-related processes.

The mild steel corrosion has been studied in hot tap water (50 °C) using linear polarization technique in the laboratory set-up that models water circulating system. The influence of water flow rate (0.15–0.45 m/s) and water supply rate (0–70 % of system volume per hour) on corrosion kinetics have been investigated. The corrosion products, formed on the surface of the steel corrosion probes, have been analyzed with XRD. It has been found, that in condition of low water flow rate (0.15 m/s) and in the absence of water supply the corrosion rate is high (0.29 mm/year) due to low blocking abilities of the surface deposits. Amorphous Fe(OH)3 is the main corrosion product to be detected on the surface. The increase in water flow rate above 0.15 m/s and water supply rate above 30 % of system volume per hour leads to the 1.6 times corrosion rate reduction (to 0.18 mm/year) due to the formation of dense surface layer of calcium carbonate and iron oxyhydroxides. The results obtained can be utilized to improve the corrosion performance of hot water supply systems.

The structures of starch and starch-based materials determine additives migration from material matrix. Propionylated starch derived from waxy, normal, G50 and G80 starch were selected as the matrix, the amylose effect on plasticizer (triacetin) migration as well as structural changes in hydrophobic starch-based films were discussed. The constant (k1) of first-order rate and initial release rate (V0) of triacetin migration were consistent with the increment of amylose content. Meanwhile, diffusion model disclosed that Fick's second law was apposite to characterize the short-term migration of triacetin, and larger diffusion coefficient (D) values of short- and long-term migration were also found in films with higher amylose content, indicating that amylose-formed structures were in favor of triacetin migration. In comparison of propionylated amylopectin, Van der Waals's interactions between propionylated amylose and triacetin were easier to be weakened with the migration of triacetin, which promoted the decrease of wavenumber of C-O-C, and enlarged the inter-planner spacing of crystalline structures, promoting the formation of amorphous structures and wrinkles and embossments in films with higher amylose content. This work confirmed that regulating the structures of starch were effective to control the migration behavior of additives from starch-based films.

A porous support with sufficient strength and high UV transmittance is of key importance for potential applications of the light conducting photocatalytic membrane reactors. In this work, we report a simple method for the preparation of amorphous fused silica support with boric acid as sintering aid. The effect of experimental conditions on sintering was investigated by orthogonal test. The effect of porosity and refractive index of pore medium on the UV transmittance of the supports was also studied. It is demonstrated that boric acid not only assists the sintering of the fused silica supports with short sintering time, but also inhibits the crystallization of cristobalite. Fused silica supports prepared at 1150 °C for 1 h show average porosity of 42.3%, bending strength of 14.9 MPa and UV transmittance as high as 64.2% in water. These properties make fused silica a good candidate as support for light conducting photocatalytic membrane reactors.

Efficient and selective catalysts are pivotal for the chemical industry. The functionalization of benzene plays vital role in petrochemical industry by converting benzene to other value-added chemicals such as phenols, anilines, etc. In industry Phenol production is based on the cumene process, which produces hazardous cumene hydroperoxide as an intermediate also equimolar of acetone a coproduct. So, the direct oxidation of benzene to phenol is desirable. Most of the developed catalyst requires an elevated temperature and suffer from low conversion. So, here we designed a series of hollow amorphous nanostructure based on MIL-100 with metal nodes of Fe3+, Cr3+, Al3+, Sc3+ by sandwiching nanoparticles such as (Pt, Rh, Ru) in between hollow amorphous Metal–Organic-Frameworks with enhanced diffusion for highly selective benzene oxidation. We have achieved benzene conversion 52% and selectivity 99.5% for phenol.

Dinaphtho[2,1-b:1′,2′-d]thiophene (DNT) is one of the “dynamic thiahelicenes” that is obtained as a racemate due to its low energy barrier for enantiomerization. Careful evaluation of both the metastable DNT film and the stable films of DNT/polymethyl metacrylate (PMMA) blends revealed that DNT has an extra-high refractive index of 1.808 at 633 nm, which is rarely achieved in organic small molecules. The fundamental factors responsible for the unusual observation of DNT were explored by comparing the properties of DNT with those of a flat-shaped dibenzothiophene (DBT) both in experiments and DFT calculations, and by analysing them with the Lorenz-Lorentz equation. It became clear that the unique properties of DNT were based on its flexible dynamic thiahelicene structure, leading to the metastable film-forming ability, the high compatibility with PMMA, and the exhibition of an extra-high refractive index caused by the dense packing in the amorphous film. Chemical modification of DNT provided new halogen-free vinyl monomers, which could be easily polymerized to form vinyl polymers with high refractive indices of 1.72-1.74, as well as film-forming ability, high thermal stability, and high transparency in the visible region. Thus, we could demonstrate that the DNT structure is a new promising candidate for organic polymeric high refractive index materials.

In a study to provide ground truth data for mid infrared observations of the surface of Mercury with the MERTIS (Mercury Radiometer and Thermal Infrared Spectrometer) instrument onboard the ESA/JAXA BepiColombo mission, we have studied 17 synthetic glasses. These samples have the chemical compositions of characteristic Hermean surface areas based on MESSENGER data. The samples have been characterized using optical microscopy, EMPA and Raman spectroscopy. Mid infrared spectra have been obtained from polished thin sections using Micro FTIR, and of powdered size fractions of bulk material (0-25, 25-63, 93-125 and 125-250 micron) in the 2.5 to 18 micron range. The synthetic glasses display mostly spectra typical for amorphous materials with a dominating, single Reststrahlen Band (RB) at 9.5 micron to 10.7 micron. RB Features of crystalline forsterite are found in some cases at 9.5 to 10.2 micron, 10.4 to 11.2 micron, and at 11.9 micron. Dendritic crystallization starts at a MgO content higher than 23 wt.% MgO. The Reststrahlen Bands, Christiansen Features (CF), and Transparency Features (TF) shift depending on the SiO2 and MgO contents. Also a shift of the Christiansen Feature of the glasses compared with the SCFM (SiO2/(SiO2+CaO+FeO+MgO)) index is observed. This shift could potentially help distinguish crystalline and amorphous material in remote sensing data. A comparison between the degree of polymerization of the glass and the width of the characteristic strong silicate feature shows a weak positive correlation. A comparison with a high-quality mid-IR spectrum of Mercury shows some moderate similarity to the results of this study, but does not explain all features.

Objective: The study was aimed to improve the dissolution and bioavailability of developed stable amorphous solid dispersions (SDs) of pioglitazone hydrochloride (PGH), a poorly water-soluble drug. Significance: Poor aqueous solubility of PGH was overcome by the design of SDs. Level A correlation demonstrated between in vitro release and bioavailability of PGH, suggest its biowaiver potential. Methods: The effects of semicrystalline copolymers (poloxamer 407 and gelucire 50/13) and methods of preparations on dissolution behavior, in vivo performance, and stability of PGH SDs were investigated. All the SDs were characterized by FTIR, TGA, DSC, XRD, and SEM. Results: FTIR and TGA showed the compatibility with the polymers. The significant change in melting pattern of the PGH observed in the DSC thermograms supported by XRD patterns & SEM indicated a change from a crystalline to an amorphous state. Gelucire 50/13 was observed to have greater ability to form SDs than poloxamer 407 in solvent evaporation method (SM). Prevention of recrystallization during storage suggested stability of the formulation. Gelucire 50/13 based SD, prepared by SM remarkably increased the dissolution within 15 min (87.27 ± 2.25%) and was supported by dissolution parameters (Q15, IDR, RDR, % DE, f1, f2). These SDs showed pH-dependent solubility. In vivo test showed significantly (p < .05) higher AUC0–t and Cmax, which were about 3.17 and 4.34 times that of the pure drug respectively. Conclusion: Gelucire 50/13 was found to be a suitable carrier for SM for preparation of SDs of PGH as evident from increased dissolution and bioavailability.

The structural investigation of the a-Si:H material, deposited at different pressures by PECVD process, has been carried out to analyze the signatures of diffused intermediate sort of crystalline phases within the amorphous silicon matrix. Raman characterization along with the Photoluminescence (PL) and spectroscopic ellipsometry studies were carried out to understand the microstructuree of these films. From Raman analysis the material was found to have indistinguishable crystalline phase, which can also be named as “intermediate amorphous phase” (a phase defined between amorphous and ultra nano-crystalline silicon) with crystalline volume fractions as 56 % and 62 % for 0.23 Torr and 0.53 Torr respectively. Here the contribution of ultra nano-crystallites results in higher crystalline fraction, which is not visibly revealed from the Raman spectra due to its sub nano-crystallite characteristics. For the film deposited at 0.53 Torr stable photo-conductance in conjunction with high photo-response under 10 hour light soaking has been observed, which is as expected due to high crystalline volume fraction. The presence of these phases might be the possible reason for the distinct device characteristics though having nearly the similar electrical properties (photo-response ~10 4 ). These studies will help to make improvement in the individual layer properties, other than the interface effect, in the fabrication of efficient p-i-n solar cells. Copyright © 2016 VBRI Press

Green fluorescent proteins (GFP) are commonly used as fluorescent tags and biosensors in cell biology and medicine. However, the propensity of GFP-like proteins to aggregate and the consequence of intermolecular interaction for their application have not been thoroughly examined. In this work, alternative aggregation pathways of superfolder green fluorescent protein (sfGFP) were demonstrated using a spectroscopic and microscopic study of the samples prepared by equilibrium microdialysis. Besides oligomerization of native monomers, we showed for the first time the condition-specific formation by sfGFP of either amyloid fibrils (at increased temperature or acidity) or amorphous aggregates (at physiological conditions). Both types of sfGFP aggregates had lost green fluorescence and were toxic to cells. Thus, when using GFP-like proteins as fluorescent tags, one should take into account their high ability to form aggregates with lost unique visible fluorescence in the cellular environment, which affects cell viability. Moreover, the results of this work cast doubt on the correctness of the data on the fibrillogenesis of various amyloidogenic proteins obtained using their fusion with GFP-like proteins.

This study reports for the first time the use of amorphous mixed cobalt-cerium metal oxides (Co10-aCeaOx), obtained by photochemical metal-organic deposition, for 5-hydroxymethylfurfural (HMF) oxidation. The optimized Co8Ce2Ox exhibited a good electrocatalytic activity toward HMF oxidation with a current density of 2.8 mA cm-2 at 1.60 V, which is 1.4 times higher than that of pure CoOx. Operando Raman spectra reveal that the incorporation of Ce altered the electronic structure of the composite by facilitating the formation of CoOOH/CoO2, thus promoting catalytic activity. Notably, it is found that the oxidation of HMF proceeds dominantly via the oxidation of the alcohol group, followed by its subsequent oxidation in both alkaline and neutral media. Due to the stability of the aldehyde group in neutral media, high valuable 2,5-diformylfuran (DFF) with the selectivity of 60%-92% was obtained, thus open the new route for electrocatalytic DFF production.

In this research study, poly(methyl methacrylate) (PMMA) polymer was selected and irradiated with alpha particles at various times. The alterations in the structure, optical parameters, and electrical properties of PMMA polymer caused by alpha particles have been assessed using XRD, ultraviolet–visible (UV/Vis) spectrophotometry and dc electric circuit, respectively. The results showed halo peaks in the XRD patterns, which indicate the amorphous nature of this type of polymer. The UV/Vis spectra demonstrated that absorption increases while transmittance decreases with an increase in the exposure time. Use of PMMA polymer as alpha dosimeters using the UV/Vis spectroscopic technique was investigated. The optical energy-gap values decreased from 3.44 eV to 3.01 eV. Furthermore, the refractive index values of all studied samples increased. Increasing the alpha radiation time enhanced dc-conductivity as well.

Solid polymer electrolytes have been broadly studied due to their wide applications in various electrochemical devices. In the present work, the electrical properties of polyaniline and its composites with BaSO4 have been studied. The polymerization of aniline monomer via the ordinary chemical polymerization process showed an amorphous structure. Whereas, in the presence of BaSO4 as a seed, the aniline is polymerized in an orthorhombic crystalline structure on the BaSO4-surface. Two composite samples of PANI and BaSO4 with different amounts of BaSO4 (1.5 and 2.5 wt%) were prepared and analyzed using XRD, FT-IR, SEM, and XPS techniques. The ac- electrical studies on the composites showed an enhancement in the electrical conductivity of PANI due to the addition of BaSO4. Ac- conductivity at frequency 500 kHz, and 100 °C, showed values of 1.9 × 10−3, 5.4 × 10−4, 1.6 × 10−1, and 1.9 × 10−1 S/cm for PANI, BaSO4, BaSO4/PANI 1.5 wt%, and BaSO4/PANI 2.5 wt%, respectively.

In this study, two-channel thin-film transistors (TC TFTs) using sputtered-deposited amorphous indium-gallium-zinc oxide (a-IGZO) as a channel layer and atomic-layer-deposition Al₂O₃ as gate insulator (GI) are proposed for wearable and portable device application. Symmetric-TC (S-TC) TFT structure consisted of conventional bottom gate (BG) TFT stacked on top of top gate (TG) TFT. Asymmetric-TC (A-TC) TFT contained BG TFT with tandem structure on the TG TFT. It was shown that the TC TFTs exhibited excellent performance such as high field-effect mobility ( $μ_{FE}$ ) and on/off current ratio ( $I_{t{on/off}}$ ) at low voltages (

Amorphous aluminum oxide (alumina) thin films are of interest as inert chemical barriers for various applications. However, the existing literature on the aqueous stability of atomic layer deposited (ALD) amorphous alumina thin films remains incomplete and, in some cases, inconsistent. Because these films have a metastable amorphous structure─which is likely partially hydrated in the as-deposited state─hydration and degradation behavior likely deviate from what is expected for the equilibrium, crystalline Al2O3 phase. Deposition conditions and the aqueous solution composition (ion content) appear to influence the reactivity and stability of amorphous ALD alumina films, but a full understanding of why these alumina films hydrate, solvate, and/or dissolve in near-neutral pH = 7 conditions, for which crystalline Al2O3 is expected to be stable, remains unsolved. In this work, we conduct an extensive X-ray photoelectron spectroscopy investigation of the surface chemistry as a function of water immersion time to reveal the formation of oxyhydroxide (AlOOH), hydroxide (Al(OH)3), and possible carbonate species. We further show that brief postdeposition exposures of these ALD alumina films to an air plasma anneal can significantly enhance the film's stability in near-neutral pH aqueous conditions. The simplicity and effectiveness of this plasma treatment may provide a new alternative to thermal annealing and capping treatments typically used to promote aqueous stability of low-temperature ALD metal oxide barrier layers.

A new method of pre-cladding amorphous glass and glass-ceramic brazing was invented to obtain a high-reliability bonding of yttrium iron garnet ferrite (YIG) and magnesium titanate ceramic (MTC) at a relatively low temperature of 725oC. The amorphous glass cladding could alleviate the stress generated by thermal expansion difference between the glass ceramic and base materials. The microstructure shows that micron-scale and nanoscale CoFe2O4 phases were dispersed in the glass seam. The joint shear strength reached 117 ± 6.6 MPa due to the enhancement of CoFe2O4 phases, which was twice as that of the joint directly brazed by amorphous bismuth glass. Correspondingly, the joint weak area was transferred from the glass matrix to the vicinity of the interface and the base material, providing a direct evidence that the glass seam was strengthened by the glass ceramic. It is significant for improving high reliability of the microwave devices for long-term service.

The structure of Ni active sites supported on amorphous silica-alumina supports with different contents of Al2O3 loadings in relation to their activities in ethylene oligomerization were investigated. Two kinds of Ni sites were detected by in situ FTIR-CO and H2-TPR experiments, that are Ni2+ cations as grafted on weak acidic silanols and Ni2+ cations at ion-exchange positions. The ethylene oligomerization activities of these Ni/ASA catalysts were found an ascending tendency as the Al2O3 loading decreased, which could be attributed to the enriched concentration of Ni2+ species on acidic silanols with a weaker interaction with the amorphous silica-alumina support. These Ni2+ species were more easily to be evolved into Ni+ species, which has been identified to be the active sites of ethylene oligomerization. Thus, it seems reasonable to conclude that Ni2+ species grafted on acidic silanols were the precursors of active sites.

In situ formation of composite micro-mesoporous dendritic fibrous nano-silica (DFNS) and Al-DFNS was prepared using a cetylpyridinium bromide (CPB) template synthetic system. Dealumination is induced by impregnation of zirconium with flux followed by a sulfuric acid treatment. This procedure results in a series of highly uniform nano-spheres, which exhibit stronger acid property than that of Al-MCM-41. In the selective alkylation of anthracene with tert‑amyl alcohol, SO42− modified Zr-contained dealuminated Al-DFNS (SZ-DeAl-DFNS) shows great catalytic activity and higher conversion (60.8%). The DFNS samples were characterized with XRD, SEM, TEM, NH3-TPD and other techniques. The results reveal that DFNSs consist of center-radial micro-mesopores and that the acid contribution of SZ-DeAl-DFNS is much broader, as compared with amorphous aluminosilicate

Background Easily separable and recyclable photocatalysts are highly desirable as they solve the problem of catalyst loss during its separation or reuse in wastewater treatment. Therefore, designing newer multifunctional semiconducting thin films using advanced physical deposition technique and chemical methodologies could be an effective way to fabricate an efficient, recyclable photocatalyst. Method Reusable and flexible NiO-MoS2@polyaniline (NiO-MoS2@Pani) conducting photocatalyst substrate was fabricated by chemical methodology to develop MoS2@Pani and later subjecting it to Direct Current (DC) sputtering to deposit NiO on it. The morphological analysis showed embedded MoS2 in Pani along with the surface covering by NiO. The XRD showed the amorphous nature of the composite, while the XPS confirmed the presence and coating of NiO over MoS2@Pani. Significant findings A synergistic effect of Pani, MoS2 and NiO in NiO@Pani-MoS2 exhibited 90% degradation of 2-chlorophenol (2-CP) under solar light irradiation. The high catalytic efficiency is ascribed to the increased separation of charge carriers and bandgap engineering due to the constituents' synergistic/additional effect. The formation of heterojunctions between NiO, Pani, and MoS2, i.e., MoS2│Pani, NiO│Pani, NiO│MoS2, and ternary heterojunction like NiO│MoS2│Pani and NiO│Pani│MoS2 are mainly responsible for the better decomposition of 2-CP. After five-time reuse, the NiO@Pani-MoS2 showed promising efficacy and stable morphology, confirming that NiO@Pani-MoS2 thin film is an efficient, easily separable, reusable, and stable photocatalyst.

We present the creation of a unique nanostructured amorphous/crystalline hybrid silicon material that exhibits surface enhanced Raman scattering (SERS) activity. This nanomaterial is an interconnected network of amorphous/crystalline nanospheroids which form a nanoweb structure; to our knowledge this material has not been previously observed nor has it been applied for use as a SERS sensing material. This material is formed using a femtosecond synthesis technique which facilitates a laser plume ion condensation formation mechanism. By fine-tuning the laser plume temperature and ion interaction mechanisms within the plume, we are able to precisely program the relative proportion of crystalline Si to amorphous Si content in the nanospheroids as well as the size distribution of individual nanospheroids and the size of Raman hotspot nanogaps. With the use of Rhodamine 6G (R6G) and Crystal Violet (CV) chemical dyes, we have been able to observe a maximum enhancement factor of 5.38 × 106 and 3.72 × 106 respectively, for the hybrid nanomaterial compared to a bulk Si wafer substrate. With the creation of a silicon-based nanomaterial capable of SERS detection of analytes, this work demonstrates a redefinition of the role of nanostructured Si from an inactive to SERS active role in nano-Raman sensing applications.