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As a promising hydrogen storage material, the practical application of magnesium is obstructed by the stable thermodynamics and sluggish kinetics. In this paper, three kinds of NiTiO3 catalysts with different mole ratio of Ni to Ti were successfully synthesized and doped into nanocrystalline Mg to improve its hydrogen storage properties. Experimental results indicated that all the Mg-NiTiO3 composites showed prominent hydrogen storage performance. Especially, the Mg-NiTiO3/TiO2 composite could take up hydrogen at room temperature and the apparent activation energy for hydrogen absorption was dramatically decreased from 69.8 ± 1.2 (nanocrystalline Mg) kJ/mol to 34.2 ± 0.2 kJ/mol. In addition, the hydrogenated sample began to release hydrogen at about 193.2 °C and eventually desorbed 6.6 wt% H2. The desorption enthalpy of the hydrogenated Mg-NiTiO3-C was estimated to be 78.6 ± 0.8 kJ/mol, 5.3 kJ/mol lower compared to 83.9 ± 0.7 kJ/mol of nanocrystalline Mg. Besides, the sample revealed splendid cyclic stability during 20 cycles. No obvious recession occurred in the absorption and desorption kinetics and only 0.3 wt% hydrogen capacity degradation was observed. Further structural analysis demonstrates that nanosizing and catalyst doping led to a synergistic effect on the enhanced hydrogen storage performance of Mg-NiTiO3-C composite, which might serve as a reference for future design of highly effective hydrogen storage materials.

Catalysis today 376, S0920586121002856 (1-10) (2021). doi:10.1016/j.cattod.2021.06.018, The objective of this research was to investigate how the photocatalytic activity of pure TiO$_2$ can be improved bySnO$_2$ modification. Different molar ratios of tin to titanium were prepared. The correlation between tin concentration and structural properties was investigated to explain the mechanism of photocatalytic efficiency and to optimize the synthesis conditions to obtain enhanced activity of the SnO$_2$-modified TiO$_2$ photocatalysts under UV-irradiation. The SnO$_2$-modified TiO$_2$ photocatalysts were prepared by a low-temperature sol-gel method based on organic tin and titanium precursors. The precursors underwent sol-gel reactions separately to form SnO$_2$-TiO$_2$ sol. The sol-gels were deposited on a glass substrate by a dip-coating technique and dried at 150 °C to obtain the photocatalysts in the form of a thin film. To test the thermal stability of the material, an additional set of photocatalysts was prepared by calcining the dried samples in air at 500 °C. The photocatalytic activity of the samples was determined by measuring the degradation rate of an azo dye. An increase of up to 30% in thephotocatalytic activity of the air-dried samples was obtained when the TiO$_2$ was modified with the SnO$_2$ in a concentration range of 0.1–1 mol.%. At higher SnO$_2$ loadings, the photocatalytic activity of the photocatalystwas reduced compared to the unmodified TiO$_2$. The calcined samples showed an overall reduced photocatalyticactivity compared to the air-dried samples. Various characterization techniques (UV-Vis, XRD, N2-physisorption,TEM, EDX, SEM, XAS and photoelectrochemical characterization) were used to explain the mechanism for the enhanced and hindered photocatalytic performances of the SnO$_2$-modified TiO$_2$ photocatalysts. The results showed that the nanocrystalline cassiterite SnO$_2$ is attached to the TiO$_2$ nanocrystallites through the Sn-O-Ti bonds. In this way, the coupling of two semiconductors, SnO$_2$ and TiO$_2$, was demonstrated. Compared to single-phase photocatalysts, the coupling of semiconductors has a beneficial effect on the separation of charge carriers, which prolongs their lifetime for accessibility to participate in the redox reactions. The maximum increase in activity of the thin films was achieved in the low concentration range (0.1–1 mol.%), which means that an optimal ratio and contact of the two phases is achieved for the given physical parameters such as particle size, shape and specific surface area of the catalyst., Published by Elsevier, Amsterdam

3D electrodes have shown extraordinary promise for electrochemical energy storage devices in wearable electronics. However, it is still a significant challenge to rationally design 3D electrode that has the characteristics of lightweight, flexibility, low cost, high performance and miniaturization. In this work, we present a novel design of 3D electrode by directly growing the nanocrystalline TiO2 film on carbonized eggshell membrane. The unique architecture can supply not only a continuous electron transport pathway through an interconnected carbon fibrous network but also an efficient electrolyte flux via an interpenetrating porous network. Besides, nanocrystalline TiO2 film on carbonized eggshell membrane offers a short ion diffusion path in the solid-phase, leading to a rapid kinetic of electrochemical reaction. When tested as an anode for Li-ion battery, TiO2 film in 3D electrode demonstrated excellent electrochemical performance with a large reversible capacity, excellent rate capacity and long life cycling property.

To endow Ti-based orthopedic implants with strong bactericidal activity, a ZnO nanorods-patterned coating (namely ZNR) was fabricated on Ti utilizing a catalyst- and template-free method of micro-arc oxidation (MAO) and hydrothermal treatment (HT). The coating comprises an outer layer of ZnO nanorods and a partially crystallized inner layer with nanocrystalline TiO2 and Zn2TiO4 embedded amorphous matrix containing Ti, O and Zn. During HT, Zn2+ ions contained in amorphous matrix of the as-MAOed layer migrate to surface and react with OH− in hydrothermal solution to form ZnO nuclei growing in length at expense of the migrated Zn2+. ZNR exhibits intense bactericidal activity against the adhered and planktonic S. aureus in vitro and in vivo. The crucial contributors to kill the adhered bacteria are ZnO nanorods derived mechano-penetration and released reactive oxygen species (ROS). Within 30 min of S. aureus incubation, ROS is the predominant bactericidal contributor with quantitative contribution value of ∼20%, which transforms into mechano-penetration with prolonging time to reach quantitative contribution value of ∼96% at 24 h. In addition, the bactericidal contributor against the planktonic bacteria of ZNR is relied on the released Zn2+. This work discloses an in-depth bactericidal mechanism of ZnO nanorods., Graphical abstract Image 1, Highlights (1) A templates and catalysts-free method is used to fabricate ZnO nanorods on Ti (2) ZnO nanorods-arrayed coating shows intense broad-spectrum bactericidal activity (3) Main bactericidal contributor of ZnO nanorods to adhered bacteria is mechano-puncture (4) Main bactericidal contributor of ZnO nanorods to planktonic bacteria is released Zn2+

This study coated the surface of irregularly shaped 5-μm boron particles with TiO2 nanoparticles to improve the ignition performance of the boron. A simple and inexpensive chemical method was used to coat the surface of boron with TiO2. Five different samples of boron coated with TiO2 nanoparticles were obtained by varying the concentration of Ti precursor. Surface structures were analyzed using different characterization techniques, which showed the formation of nanocrystalline TiO2 nanoparticles over the boron surface. The nanoparticles of TiO2 were well dispersed over the boron surface, and exhibited strong interfacial contact with the boron. The oxidation of boron and boron coated with TiO2 was analyzed by thermogravimetric technique in an air atmosphere from room temperature to 1000 °C. Results revealed that the oxidation of boron started at a temperature approximately 162 °C lower after coating with TiO2. The ignition behavior of the boron and boron coated with TiO2 particles was studied using a shock tube. The results of the shock tube experiments demonstrated the TiO2 coated boron had a shorter ignition delay time than the bare boron. An approximate 35% reduction was observed in the ignition delay time of boron after coating with TiO2 nanoparticles, showing its potential value in high energy density fuels.

Although the optical properties of nanocrystalline cesium tungsten bronze have been widely studied, there is a lack of research on the effect of particle size on its optical properties. In order to further investigate size and shape effect on the NIR shielding performance, cesium tungsten bronze nanoparticles with different sizes and morphologies were prepared by two methods. The size of irregular shaped samples prepared by solvothermal method is tens of nanometers, while the size of hexagonal prism shaped samples prepared by solid state reaction method is hundreds of nanometers. The element spectrums shows that there are more oxygen vacancies in large particles than in small particles. The NIR shielding performance of large particles far lower than that of small particles, indicating that the influence of shape and size on optical properties is more obvious than that of oxygen vacancy. Theoretical calculation on hexagonal prism shaped particles exhibits that the NIR extinction of large aspect ratio is better at longer wavelength and small aspect ratio is better at shorter wavelength.

Here, the up-and down-conversion emissions enhancement in Er3+/Yb3+/Li+ co-doped Y4O(OH)9NO3 and Y2O3 nanoparticles was studied in function of the calcination temperature. Tri-doped Y4O(OH)9NO3 nanophosphors were synthesized by the hydrothermal method and then calcined to yield Y2O3 nanocrystalline structures. The phase evolution from Y4O(OH)9NO3 to Y2O3 was investigated by XRD analysis, and the quantification of Li + species in the nanoparticles lattice was done by FTIR. Both techniques allow explaining the photoluminescence enhancement in terms of the calcination temperature required to achieve optimum lithium incorporation. SEM analysis was used to monitor changes in the morphology with the thermal treatment temperature. The resulting photoluminescence emission spectra of the Er3+/Yb3+ doped Y4O(OH)9NO3 and Y2O3 nanocrystals were composed of emission bands associated with the Er3+ 2H11/2, 4S3/2 → 4I15/2 (green), 4F9/2 → 4I15/2 (red), and 4I13/2 → 4I15/2 (infrared) intraelectronic transitions, and its relative contribution was found to be sensitive to the calcination temperature. Thus, tunable color emission from yellowish-orange to yellow-green light with a color temperature of 2581–4433 K upon 980 nm excitation, respectively, was observed.

We report nearly full densification of polycrystalline rhombohedral beta (β)-boron without the addition of sintering aids via spark plasma sintering (SPS). The analytical aberration corrected transmission electron microscope observations have revealed in-situ growth of nanocrystalline boron-rich oxide precipitates that contain approximately 4 at.% of oxygen and beget the densification of β-boron. Further electron energy loss spectroscopy and diffraction analysis confirmed that the newly formed boron-rich oxide (nominally B96O4) structure with B-O σ-bonding belongs to space group R 3 ¯ m . Depth sensitive nanoindentation showed boron-rich oxide phase has a hardness of about 41 ± 2 GPa, which is 10% higher than that of β-boron matrix. The estimated hardness and fracture toughness of β-boron were approximately 31 GPa and 2.2 MPa m1/2, respectively, using Vickers microindentation, which falls in the range of those commercially used boron carbides. These results suggest that the enhanced densification and mechanical properties arise from the newly formed boron-rich oxide in β-boron during SPS experiments.

Synthesis of nanostructured carbon allotropes using CO2 as a cheap carbon source is challenging and usually limited by high temperature activation. Herein, formation of 3D nanostructured carbon allotropes including nano-graphene and single crystalline nanodiamond films is feasible at room temperature on various single crystal metals (e.g., Bi, Ag, Zn, and Co) that were formed under the dynamic CO2 electrochemical reduction reaction environment at relatively low applied potential (−1.1 to −1.6 V vs. Ag/AgCl). The nanocrystalline carbon was obtained as the major products from CO2 (≥96% selectivity, ∼1 μm thickness) without any liquid products. Upon applying the negative potential, nanoclustering of the self-limiting ultrathin metal oxide layers of metal particles on the highly conductive substrate could lead to formation of negatively charged metal clusters, which were well stabilized by the ternary electrolyte system containing [BMIm]+[BF4]-/propylene carbonate/water. This system allows the reduction of CO2 into single atoms C∗ and the subsequently electrocrystallization of C∗ into carbon allotropes on the crystallographic planes of the single crystal metals formed as the building blocks. The CO2-derived Ag–C/epoxy composites show promising thermal conductivity. The results present a breakthrough advancement in the growth of nanostructured carbon allotropes from CO2 by the viable negative CO2 emission approach.

Dual-emitting manganese ions singly doped 5ZnO-(5–2.5x)Ga2O3-2.5 xAl2O3–90SiO2 glass-ceramic (GCs) samples, containing the alloyed Zn(Ga, Al)2O4 nanocrystals with a size of about 5 nm, were successfully prepared by a sol-gel method under different heat treatment temperatures, demonstrating an excellent white light emission. We found that the formation of the ZnGa2O4 nanocrystals began at 650 °C (absence of Al2O3, x = 0) while that of the ZnAl2O4 crystals required a higher temperature of about 900 °C (presence of Al2O3, x = 2) in SiO2 glasses. A nanostructured Zn(Ga, Al)2O4:Mn2+, Mn4+ in the glass-ceramic was synthesized by Al3+ replacing part of Ga3+. The doping of Al3+ has effectively contributed to the existence of Mn2+, thus realizing the regulation of the valence state of manganese ions. The glass ceramic samples showed red emission arrived from the 2Eg → 4A2g transitions of Mn4+, green emission originated from the 4T1→6A1 transition of Mn2+, and blue emission derived from the self-activation center of ZnGa2O4 nanocrystalline. In particular, the 0.1%Mn doped the 5ZnO-(5–2.5x)Ga2O3-2.5xAl2O3–90SiO2 glass-ceramic samples can provide white color emission depending on the Al doping concentration (x), x = 0.4–0.9 and the annealing temperature, 650–900 °C.

A diamond film was synthesized by chemical vapor deposition, where a hot graphite plate was used to thermally activate methane and hydrogen. The effect of parameters on the diamond films grown, such as pressure ranging from 40 to 100 torr, methane concentration in hydrogen varying from 0.5 to 2 vol %, and substrate temperatures from 1020 to 1140 °C, were studied. Diamond films with nanocrystalline to polycrystalline crystal sizes were obtained. A maximum growth rate of 0.8 μm/h was obtained, and the quality is comparable to diamond films synthesized by the hot metal filament chemical vapor deposition method. In contrast to the hot filament method, this method does not use a metallic filament as thermal activator. Therefore, the diamond films contain no metal contaminants and thus can be used for electronic and biomedical applications. The absence of metal contaminants was confirmed using different methods.

It is challenging to develop a material that combines good mechanical properties and high translucency since these properties are generally not coincident in one material. In this study, we prepared ZrO2-SiO2 nanocrystalline glass-ceramics that combines the above two types of properties. Raw powder with 55 mol%, 65 mol%, and 75 mol% ZrO2 and each with 5 mol% yttrium as a dopant was prepared by sol-gel method, followed by spark plasma sintering to obtain dense glass-ceramics. XRD results demonstrated that the glass-ceramics with 65 mol% and 75 mol% ZrO2 were composed of tetragonal-ZrO2, whereas, that with 55 mol% ZrO2 was composed of cubic-ZrO2. The as-sintered glass-ceramics showed black/brown discoloration, but they obtained high translucency after thermal treatment. X-ray energy-dispersive spectrometry (EDS) results in scanning electron transmission microscopy (STEM) mode demonstrated yttrium dopants were predominately distributed in ZrO2 nanocrystallites. The glass-ceramics with 65 mol% ZrO2 had the highest flexural strength, achieving an average value of 673 MPa. The glass-ceramics with different compositions sintered at different temperatures showed fracture toughness values ranging from 5.25 MPa m1/2 to 6.69 MPa m1/2. The strong and translucent ZrO2-SiO2 nanocrystalline glass-ceramics showing great protentional to be used in many fields.

The present work reports the structural, morphological, and optical analysis of rare earth metal ion (Nd3+) doped Titanium Dioxide Nanoparticles. Titanium Dioxide doped with Neodymium ions (1 wt% and 4 wt%) have been studied by X-ray diffraction (XRD) Aanlysis, High Resolution Transmission Electron Microscopy (HR-TEM) analysis, Energy Dispersive X-ray Analysis (EDAX), Ultraviolet–visible (UV–Vis) spectroscopic analysis. The powder X-ray diffraction patterns ensured the nanocrystalline anatase formation of all the samples. The morphology and particle size of the TiO2 host matrix were confirmed by High Resolution Transmission emission electron microscopy (HR-TEM). The particle size trend obtained from HR- TEM images is acceptable with the crystal size obtained from XRD results. Ultraviolet–visible measurements were carried out to investigate the optical properties of our powdered titania. The dye sensitized solar cells were fabricated with these as-synthesized materials as the photoanode and the J-V measurement shows improved high open circuit voltage, short circuit current and high efficiency achieved.

Utilizing eggshells to synthesize a value added product like nanocrystalline hydroxyapatite (HA) has received a lot of attention from researchers since they are composed of CaCO3 with biologically essential trace elements such as Mg, Si, etc. Different biomedical applications need HA with appropriate nanoscale characteristics like crystallinity, particle size, morphology, surface area, mesoporous nature, etc. The same can be achieved by tuning the reaction parameters, choosing a suitable mode of preparation and utilizing organic modifiers. Here, we report the rapid synthesis of eggshell derived HA in the presence different organic modifiers using a custom built microwave reactor employing the previously optimized parameters. The synthesis process is relatively rapid and gets completed in 5 min. The absence of an organic modifier yielded inhomogeneous size nanorods in the range of 40 – 600 nm. Ethylenediaminetetraacetic acid (EDTA) assisted synthesis resulted in a flower like 1.67 ± 0.12 μm sized HA. Whereas polyethylene glycol 6000 (PEG) and cetyltrimethylammonium bromide (CTAB) assisted synthesis produced aggregated nanorods of length 31 ± 8 and 68 ± 20 nm, respectively. While the synthesis with trisodium citrate dihydrate (TSC) resulted in needles of HA with typical length of 32 ± 8 nm. Presence of Na, Mg and Si trace elements are confirmed from the composition analysis. All the samples are found to be mesoporous in nature. The in vitro cell culture experiment carried out using fibroblast NIH 3T3 cell line clearly revealed equal or higher cell viability for the samples synthesized in presence of organic modifiers as compared to sample produced without organic modifier. Thus, from the present study we find that the synthesis of eggshell derived HA using different organic modifiers via a custom built microwave reactor can be a potential approach for the rapid preparation of precursor materials with suitable nanoscale characteristics for developing bone fillers, drug/protein delivery carriers, tissue engineering scaffolds, etc.

Aiming to gain insight on the hydrogen storage properties of Mg-based alloys, partial hydrogenation and hydrogen pressure related de-/hydrogenation kinetics of Mg–Ni–La alloys have been investigated. The results indicate that the phase boundaries, such as Mg/Mg2Ni and Mg/Mg17La2, distributed within the eutectics can act as preferential nucleation sites for β-MgH2 and apparently promote the hydrogenation process. For bulk alloy, it is observed that the hydrogenation region gradually grows from the fine Mg–Ni–La eutectic to primary Mg region with the extension of reaction time. After high-energy ball milling, the nanocrystalline powders with crystallite size of 12∼20 nm exhibit ameliorated hydrogen absorption/desorption performance, which can absorb 2.58 wt% H2 at 368 K within 50 min and begin to desorb hydrogen from ∼508 K. On the other side, variation of hydrogen pressure induced driving force significantly affects the reaction kinetics. As the hydrogenation/dehydrogenation driving forces increase, the hydrogen absorption/desorption kinetics is markedly accelerated. The dehydrogenation mechanisms have also been revealed by fitting different theoretical kinetics models, which demonstrate that the rate-limiting steps change obviously with the variation of driving forces.

Cu(In,Ga)Se2 (CIGS) is a prevalent material with superior thermo-chemical stability and excellent optoelectronic properties for solar cell applications. In thin film form, CIGS could be a potentially economical and building integrated photovoltaic adaptable substitute to Silicon solar cells, solving humanity's extensive energy demands. To be economically sustainable, CIGS thin film processing must be abridged and affordable. We explored a low-cost, simplified wet chemical nano-ink method to make the CIGS thin film absorber layer comprising precursor thin film preparation by spraying CIGS nano-ink and subsequent post-treatment using Selenium vapor under Nitrogen atmosphere at a temperature of 550 °C. The spray-casted nanocrystalline layers were selenized at a low pressure of 1 Torr or 1 atm Nitrogen utilizing elemental pallets of Selenium as a source of Se vapor. The impact of Selenization pressure on the structure, morphology, composition, and electronic conductivity of selenized CIGS thin films absorber is investigated in this study, as well as the device performance associated with the processing parameters.

SnO2 is an n-type semiconductor and a transparent conducting oxide and has apt properties in a gas sensing material, photovoltaic cells, fuel cells, batteries etc., Nanocrystalline tin oxide (SnO2) powders with different grain sizes were prepared by chemical co-precipitation method. Synthesised nanopowder XRD data were analyzed with different tools. X-ray diffraction (XRD) analysis mainly used to determine the crystal structure of nanomaterials such as ZnO, CuO, CdO and SnO2, etc., Pure SnO2 test conditions were set to be Cu-Kα XRD source, accelerating voltage 40 kV, acceleration currency 40 mA, scan range 20–80° with Ni filter (λ = 0.154056 nm). The pure SnO2 sample was exhibiting different crystalline peaks from the powder XRD study. The diffraction peak of pure tin oxide nanoparticles possesses a tetragonal rutile structure with space group P42/mnm. The FULLPROF Suite program was used for Rietveld–type analysis for pure SnO2powder diffraction data. The resultant data were compared with Nelson-Riley, Williamson-Hall plot, and Debye-Scherer methods. The lattice parameters and particle size of pure SnO2were agreed with the ICDD.No.01-077-0447data. The main advantages of these methods are low angle regions and a small number of peaks needed.

A favourable material for the optoelectronic system, nanocrystalline ceramic oxide CaBiNbO6, has been fruitfully prepared by single step auto ignition combustion method. The modified auto ignition combustion method took a vibrant role in synthesizing the nano structured oxide samples. The XRD revealed that, the sample crystallizes in orthorhombic structure without any secondary phase. The crystallite size calculated from the XRD data using the Scherrer formula is found to be 14 nm. TEM image of the as prepared sample shows a spherical morphology with a narrow particle size of nearly 19 nm. The 97 % of theoretical density of the sample with minimum porosity was attained during the sintering at 900 0C. The optical properties of the sample were studied using Ultraviolet visible absorption and Photoluminescence spectroscopy. The optical studies revealed that the material is wide band gap ceramic oxide and the optical band gap is obtained as 3.59 eV. Photoluminescence studies also revealed that the sample is a photoluminescent material with strong emissions in the visible region. The optical properties of the nano structured CaBiNbO6 makes the sample find various applications in opto-electronic systems.

Catalytic activity of TiO2, 2%Re–TiO2 and 10%Re–TiO2 in the conversion of carbohydrates into levulinic acid under autoclave conditions was evaluated. These materials were prepared by aerogel method, for the first time to the best of our knowledge, and characterized by XPS, SEM-EDX, DRIFTS, DR UV-vis, Raman, N2 adsorption/desorption isotherms, TGA and XRD. Further, the surface acidity was probed by NH3-TPD and pyridine-FT-IR where it was observed that increasing the amount of rhenium doped into TiO2 led to an increase in the total number of acid sites (Lewis + Brønsted) but with an overall lower strength. The presence of both Brønsted and Lewis acid sites led to the hypothesis that these materials may be well suited for conversion of carbohydrates into levulinic acid. Indeed a levulinic acid yield of 57% was reached over 10%Re–TiO2 for a low mass ratio catalyst to glucose (1 : 5). Moreover, the 10%Re–TiO2 catalyst was reused in the conversion of glucose for four catalytic cycles without a significant loss of the catalytic activity.

This study was conducted to implement fish collagen hydrolysate as a substrate for synthesizing a nanophasic hydroxyapatite (HA) coating that would display superior osteoinductivity than HA derived from collagen (C/HA) and to comprehend the contribution of secondary structure on HA synthesis. Collagen type I was isolated from mullet skin and fragmented to obtain collagen hydrolysate (MCH). CD, FTIR, XRD, DLS and MS studies revealed that the MCH peptides oriented in polyproline-II conformation and coiled to form a mimic-helix with a packing distance of 0.885 nm. Multiple helices self-assembled into a quasi-fibrillar network with a diameter of 931 nm. The MCH was suspended in HA-nucleating solution to form MCH/HA nanocomposite crystals, which exhibited HA-specific planes in XRD with crystal orientation towards the quasi-fibrillar axis and a % crystallinity of 96.04. MCH/HA crystals were plate-shaped with an average size of 55.4 nm and a Ca/P ratio of 1.77 with moderate resilience (9.9 GPa) and high wettability. Consequently, osteoblasts cultured on MCH/HA coated-Ti surface proliferated faster and expressed 1.2–2 times higher levels of osteogenic differentiation markers when compared to C/HA-coated and uncoated surfaces. The study identified MCH/HA to be a superior coating material, by virtue of the unique quasi-fibrillar architecture of MCH.

The effects of pH of the reaction solution and the concentration of phosphoric acid on the crystal growth behavior of LaPO4 crystallites were investigated and the mechanical properties of rare-earth phosphates were compared. As a result, the concentration of phosphoric acid of 10% was beneficial to the crystal growth of LaPO4 nanocrystalline. When the pH value of the reaction solution was 2, the size of LaPO4 crystallites increased gradually with the increasing reaction temperature, and the smallest crystallite size of 43.27 nm was obtained after heat-treatment at 1000 °C. Simultaneously, the activation energy for crystal growth of LaPO4 nanocrystalline was relatively lower (26.82 kJ mol−1). With the decreasing radii of rare-earth ions, the hardness, Young's modulus and fracture toughness of the bulk rare-earth phosphates exhibited a reduced tendency, resulted from the increase of porosity under the same preparation process.

Niobium carbide composite coatings were prepared on titanium alloy surface by plasma spraying NbC–Al2O3, Nb–SiC and Nb–SiC–Al composite powders, respectively. The phase composition, microstructure and formation mechanism of the three composite coatings were analyzed and their microhardness, toughness and scratch resistance were compared. The phases of the NbC–Al2O3 system did not change during the plasma spraying process, and new phases (Nb2C, NbC and Nb3Si) were formed in the Nb–SiC and Nb–SiC–Al systems. TEM results of the Nb–SiC composite coating indicate that the new phases nanocrystalline Nb2C, submicron NbC and nanocrystalline Nb3Si were formed during the plasma spraying process. Compared with the NbC–Al2O3 composite coating, the microstructure of the Nb–SiC and the Nb–SiC–Al composite coatings were uniform, and the porosity were relatively low, and the hardness was higher. The Nb–SiC–Al composite coating was denser than the Nb–SiC composite coating, the lamellar structure was obvious and the number of pores in the coating was the least, which is attributed to the better molten state of the composite powder by the addition of the Al to the Nb–SiC system. The Nb–SiC–Al composite coating had better toughness and scratch resistance.

In this work, we report a comparative study of Ni-based anode compositions, made of Cu and Co (40 and 80 mol%) and gadolinia-doped ceria (CGO) matrices, for application the dry reforming of methane (DRM) reaction using Solid Oxide Fuel Cells (SOFCs). The new compositions are synthesized by a one-step synthesis route, using citric acid as chelating agent, and characterized at three different stages: i) after synthesis, ii) after reduction, and iii) after DRM. X-ray diffraction (XRD) analysis combined with thermodynamic calculations is used to understand phase evolution along the different stages, revealing that complete solid solutions of NiCo- and NiCu-based alloys are formed after DRM reaction. Transmission Electron Microscopy (TEM) shows the formation of nanocrystalline powders, while surface area (SBET) measurements show higher values in the case of the NiCo-based samples. Moreover, the Co-containing compositions exhibit higher reducibility and stronger metal-ceramic interactions than the Cu-containing samples, according to the Temperature Programmed Reduction (TPR) results. Finally, DRM results demonstrate higher CO2 and CH4 conversions in the case of the Co-containing samples, as well as increased resistance towards carbon deposition, as confirmed by Thermogravimetric and Differential Scanning Calorimetry analyses (TG-DSC). Overall, the Co-based compositions are highly beneficial for their use as anodes for the CO2 reforming of methane in SOFCs.

Europium doped (0.1% and 1%) chloroborate BaO–B2O3–BaCl2 glass and glass-ceramic with embedded BaCl2 nanocrystals have been synthesised, investigated, and compared with the corresponding nanocrystalline powder. The structural analysis of the glass evidenced ionic bonds characteristic to the glass host structure and compositional changes during the melting. X-ray diffraction and transmission electron microscopy revealed the formation of orthorhombic BaCl2 nanocrystals of about tens on nm in size and a smaller amount of BaB2O4 nanocrystals. Structural analysis of the Eu2+-doped BaCl2 nanocrystals has shown a distortion of the crystalline cell assigned to the growth process, affected by defects and ionic impurities. Photoluminescence spectra of the glass-ceramic revealed Eu3+ and Eu2+ luminescent ion species, but only Eu2+ is incorporated within the BaCl2 nanocrystalline phase. Electron paramagnetic resonance measurements in X-band sustain the presence of Eu2+ ions. The EPR parameters (g values and hyperfine constants) resulting from the Q-band EPR spectra simulations recorded on glass-ceramic are similar to those in Eu2+-doped BaCl2 and confirmed the partial incorporation of Eu2+ ions within the BaCl2:Eu2+ nanocrystals in the glass-ceramics.

Cassava stems were one of the largest agricultural by products in Indonesia, especially in Lampung Province. It is known that cassava stems have a fairly high lignocellulose content, especially cellulose which reaches 39.29%. The high cellulose content in cassava stems has great potential to be used as raw material for Nanocrystalline Cellulose (NCC). The preparation of nanocrystalline cellulose consists of four main stages, namely: pre-hydrolysis, delignification, bleaching, and acid hydrolysis. The pre-hydrolysis stage was carried out by boiling a solution of CH 3 COOH and cassava stem powder for 60 minutes at a temperature of 105 o C. Cassava stem powder was then delignified using a 25% NaOH solution heated to a temperature of 105 o C for 1 hour. The bleaching stage used a 3.5% NaOCl solution at a temperature of 50 o C for 60 minutes and was carried out twice. The last step is acid hydrolysis using 2.5N HCl solution for 15 minutes at a temperature of 105 o C, then the electromagnetic induction treatment is varied with temperature variations of 30 o C, 50 o C, and 70 o C for 60 minutes. The prepared nanocrystalline cellulose were tested for lignocellulose, XRD and PSA. From the test results, the best variation of nanocrystal cellulose preparation was acid hydrolysis treatment with 70 o C electromagnetic induction for 60 minutes, namely an increase in the percentage of cellulose 62.93%, crystallinity 90.68%, and an average particle size of 18.04µm with some particles measuring nanometers. From the results of the research, it was concluded that electromagnetic induction increased crystallinity and decreased the size of nanocrystalline cellulose.

We investigated interfacial reactions of U(VI) in the presence of Suwannee River natural organic matter (NOM) at acidic and neutral pH. Laboratory batch experiments show that the adsorption and precipitation of U(VI) in the presence of NOM occur at pH 2 and pH 4, while the aqueous complexation of U by dissolved organic matter is favored at pH 7, preventing its precipitation. Spectroscopic analyses indicate that U(VI) is mainly adsorbed to the particulate organic matter at pH 4. However, U(VI)-bearing ultrafine to nanocrystalline solids were identified at pH 4 by electron microscopy. This study shows the promotion of U(VI) precipitation by NOM at low pH which may be relevant to the formation of mineralized deposits, radioactive waste repositories, wetlands, and other U- and organic-rich environmental systems.

Based on the excellent performances of nanocrystalline cellulose, sodium alginate, or K-carrageenan in Pb2+ adsorption, nanocrystalline cellulose/sodium alginate/K-carrageenan composite hydrogel beads were prepared to adsorb Pb(II) from aqueous solutions. The objective of this study was to demonstrate the excellent potential of the composite hydrogel beads for heavy metal ion adsorption. We successfully prepared ecofriendly Fe-modified nanocrystalline cellulose/sodium alginate/K-carrageenan composite hydrogel beads and characterized them. The structure and adsorption mechanism were investigated using scanning electron microscopy, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy, and the optimal adsorption conditions were determined. The tricomponent hydrogel beads were robust and exhibited improved adsorption capacity for Pb2+ and good reusability. The adsorption results could be fitted well with a pseudo-second-order kinetic model and the Langmuir adsorption model. The maximum adsorption capacity obtained by fitting was 351.04 mg g−1. Recycling experiments revealed that the adsorption capacity of the adsorbent remained high after five cycles of reuse.

Due to its to its optical, thermal, photocatalytic and electrophysical properties, nanocrystalline titanium oxide (TiO2) is widely used in various fields. In the present work, a series of pure and Gd-modified (0.5, 5, 50 mol%) TiO2 nanocrystalline powders were prepared by a novel synthesis approach – extraction-pyrolytic method (EPM). Metal containing extracts on the basis of valeric acid were used as precursors. Thermal behavior of produced individual and mixed precursors were investigated by thermogravimetric analysis (TGA) and high temperature differential scanning colometry (HDSC). Phase composition of pure and Gd-modified TiO2 powders were studied as a function of pyrolysis temperature (450o -850°C ) and gadolinium content by X-ray diffraction (XRD) method. Photocatalytic activity of produced powders was studied by photocatalytic degradation of methylene blue (MB) under UV/VIS light irradiation.

In the present work, pure nanocrystalline monoclinic Zirconia (ZrO2) has been successfully synthesized and optimized by the modified co-precipitation method. The concentration of raw material has been optimized with the fixed amount of precipitation agent (Potassium hydroxide KOH). The thermal history of the precursor has been examined through TG/DTA analysis. All the samples are subjected to study the structure, fingerprints of the molecular vibrations, and morphology analyses. The representative sample has been analyzed through Transmission Electron Microscope (TEM) and X-ray Photo Electron Spectroscopy (XPS) analyses. The as-prepared sample exhibits the better crystallinity and surface morphology with lesser particle size (190 nm) when the raw material concentration is 0.2 M. The as-prepared ZrO2 filler (0, 3, 6, 9, and 12 wt.%) is spread through the enhanced polymer electrolyte P(S-MMA) (27 Wt.%)-LiClO4 (8 wt.%)-EC + PC (1;1 of 65 wt.%) complex system via solution casting method. The as-synthesized electrolyte films are examined via complex impedance analysis. P(S-MMA) (27 wt.%)-LiCIO4 (8 wt.%)-EC + PC (1 ;1 of 65 wt.%)-6 wt.% of ZrO2 shows the high ionic conductivity 2.35 × 10–3 Scm–1. Temperature-dependent ionic conductivity studies obey the non-linear behavior. The enhanced ZrO2 has been expected to enhance the other electrochemical properties of the lithium secondary battery.

In this investigation, mechanical grinding was applied to fabricating the Mg-based alloys La7Sm3Mg80Ni10 + 5 wt.% M (M = None, TiO2, La2O3) (named La7Sm3Mg80Ni10–5 M (M = None, TiO2, La2O3)). The result reveals that the structures of as-milled alloys consist of amorphous and nanocrystalline. The particle sizes of the added M (M = TiO2, La2O3) alloys obviously diminish in comparison with the M = None specimen, suggesting that the catalysts TiO2 and La2O3 can enhance the grinding efficiency. What's more, the additives TiO2 and La2O3 observably improve the activation performance and reaction kinetics of the composite. The time required by releasing 3 wt.% hydrogen at 553, 573 and 593 K is 988, 553 and 419 s for the M= None sample, and 578, 352 and 286 s for the M = TiO2 composite, and 594, 366, 301 s for the La2O3 containing alloy, respectively. The absolute value of hydrogenation enthalpy change |ΔH| of the M (M = None, TiO2, La2O3) alloys is 77.13, 74.28 and 75.28 kJ/mol. Furthermore, the addition of catalysts reduces the hydrogen desorption activation energy ( E a de ).

Ultrafast nanostructured SnO2/graphene nanoplatelets (SnO2/GNP) composite material is synthesized by direct microwave irradiation technique. The tetragonal SnO2 phase is confirmed using powder X-ray diffraction pattern and revealed the D-band and G-band in Raman analysis for the presence of graphene nanoplatelets, quantified with 20% mass in thermogravimetric analysis. The measured surface area of SnO2/GNP composite is 50 m2 g−1 and the transmission electron microscopic results shows nanocrystalline SnO2 particles (10 nm), well-decorated on graphene nanoplatelets. The electrochemical impedance spectroscopic analyses confirm that there is no charge storage buildup in Li vs SnO2/GNP lithium cell with additive electrolyte and the cyclic voltammetric analyses reveal highly reversible characteristics of alloying-dealloying mechanism of Sn. The Galvanostatic discharge-charge studies of Li vs SnO2/GNP lithium cells with additive electrolyte are exhibited capacity fade/hysteresis abated stable cycling performance and delivered three-fold higher discharge-charge capacities of 745/738 mAh g−1 than the conventional electrolyte (220/219 mAh g−1) for the 100th cycle at 100 mA g−1. The rate studies are yielded the discharge-charge capacities of 387/383 mAh g−1 at 3000 mA g−1 and 412/410 mAh g−1 for the 500th cycle at 1000 mA g−1, as a superior anode for high-rate lithium-ion batteries.

Ball-milled nanocrystalline Mg powders catalyzed by TiO2 powder, titanate nanotubes and carbon nanotubes were subjected to intense plastic deformation by equal-channel angular pressing. Microstructural characteristics of these nanocomposites have been investigated by X-ray diffraction. Microstructural parameters, such as the average crystallite size, the average dislocation density and the average dislocation distance have been determined by the modified Williamson–Hall analysis. Complementary hydrogen desorption and absorption experiments were carried out in a Sieverts’ type apparatus. It was found that the Mg-based composite catalyzed by titanate nanotubes exhibits the best overall H-storage performance, reaching 7.1 wt% capacity. The hydrogenation kinetic curves can be fitted by the contracting volume function for all the investigated materials. From the fitted parameters, it is confirmed that the titanate nanotube additive results in far the best kinetic behavior, including the highest hydride front velocity.

3Y-TZP/3wt% Al2O3 powder was coated with varying amounts of BN using the urea and borate reaction sintering method, and then multiphase ceramics were prepared by hot pressing sintering. The micro-topography and the compositional analysis of synthesized ceramics were conducted through scanning electron microscopy, transmission electron microscopy and X-ray diffraction. A mechanical tester was used to analyze the Vickers hardness, fracture toughness, and bending strength of the synthesized ceramics. The results showed that the ceramic with a BN content of 12wt% showed the best processability, but had diminished mechanical properties (such as fracture toughness and bending strength). The ceramic with a BN content of 9wt% showed better processability than those with 3wt% and 6wt% BN. However, the fracture toughness was affected by the addition of 9wt% BN, making this ceramic only usable as a base material for a three-unit fixed bridge. In contrast, the ceramics with a BN content of 3wt% or 6wt% fulfilled the criteria for use in multi-unit restoration, but their low processability made them unsuitable for milling after sintering.

Ion irradiation induced nucleation and growth of nanoparticles in amorphous SiC at elevated temperatures are investigated in this study. Both as-deposited amorphous and Kr ion irradiation-amorphized SiC films are used for the investigation. Similar behavior of particle precipitation in the two types of the films is observed. It is found that the threshold temperature for nucleation is between 550 and 700 K, which is considerably higher than the critical temperature for full amorphization in SiC irradiated with Kr ions. There is a temperature regime up to at least 900 K, where the nucleation and growth rates are only weakly dependent of the irradiation temperature. This temperature regime is potentially useful to tailor the size and density of nanocrystalline SiC precipitates by optimizing the ion irradiation conditions.

This research investigates the oxidation behavior of nanocrystalline/amorphous Si3N4 compounds in atmospheres with different oxygen pressures. High purity nanocrystalline/amorphous Si3N4 and MgAl2O4 mixtures were used to investigate oxidation behavior of Si3N4. Si3N4-xMgAl2O4 (0

AlN-doped SiC nanocrystalline ceramics were prepared by ball milling and reactive liquid-phase spark plasma sintering (SPS), using Si, C and AlN powders as raw materials. The oxidation behavior of the ceramics was studied. The AlN-doped SiC ceramics exhibited excellent oxidation resistance at 1773 K for 50 h and the parabolic rate constant was 0.004 mg2 cm−4 h−1. Compared with SiC ceramics, AlN-doped SiC ceramics could inhibit the crystallization of silica, prevent the grain growth of cristobalite and ensure the integrity of oxide scale by healing the possible cracks during the oxidation process, resulting in the improved oxidation resistance.

Seeking highly efficient non-preference electrocatalytic materials that serve photoelectrochemical (PEC) water splitting in acidic systems is expectant in the context of environmentally friendly production. We designed Ni2P electrocatalysts synthesized in oil phases via the hot-bubbling method with superb stability in air and sulfuric acid solution for PEC, which were found with excellent hydrogen evolution performance. A tunable particle size and highly exposed (001) planes of Ni2P nanocrystals were achieved. The designed catalysts achieved a notable promotion in the hydrogen evolution reaction activity compared to that of Ni2P synthesized in the water phase. More specifically, the electrode prepared by self-assembled Ni2P nanoparticles was found to have decent over-potential of η10 = 164 mV in darkness and was further decreased to 129 mV with irradiation of visible light. The cyclic stability tests manifested brilliant durability in 0.5 M H2SO4. Measurement of the transient photocurrent response and PEC water splitting catalytic performance indicated that the Ni2P had high carrier concentration upon irradiation, lower carrier recombination probability, and prolonged photo-response lifetime (3.03-3.14 s).

This work describes the synthesis of nanocrystalline yttrium orthoferrite by simple co-precipitation method of Y(III) and Fe(III) cations in boiling water with 5% sodium carbonate aqueous solution without any surfactants. YFeO3 nanoparticles are obtained by annealing the precursors at different temperatures (600, 700, and 800 °C) for 1 h. The TEM analysis shows the particle size in the range of 50–60 nm. According to XRD data (calculated using the Scherrer formula), an increase in annealing temperature from 600 to 800 °C leads to an increase in the average crystallite size from 29.6 to 42.8 nm and in the unit cell volume from 226.40 to 228.55 A3. Synthesized YFeO3 nanoparticles have strong absorption in the UV–Vis regions (λ = 200–400 and 400–600 nm) and are soft ferromagnetic materials with high magnetization. Additionally, YFeO3 nanoparticles with a low energy bandgap (Eg ≈ 2.4 eV) are suitable for photocatalysis and can be recovered by magnets.

Molecular dynamics (MD) simulations have been implemented to examine the creep-ratcheting deformation behavior of CNT reinforced nanocrystalline aluminum specimens having grain sizes 8 nm. Hybrid potentials have been considered for three armchair CNTs reinforced NC Al nanocomposite specimens to perform creep-ratcheting simulation tests at three different temperatures (10 K, 300 K, and 467 K). The structural variations are studied along with defect evolution. The highest dislocation density has been obtained for (30,30) CNT-NC Al nanocomposite specimen. The creep-ratcheting strain is increased with temperature rise from 10 to 467 K. The Shockley partial dislocations are the major driving factor for creep-ratcheting deformation at three temperatures. The predominant stages involved in the creep-ratcheting deformation process are discussed in detail. The interface region between the NC Al and CNT has been studied for three CNTs at three temperatures during the creep-ratcheting process.

In this study, an experimental and atomic-scale simulation-based investigation has been performed to investigate the possible stability of the nano-crystalline structure and thereby considerable st...

The particle shape and size distribution of inorganic fillers play a crucial role in the scaffold buildability when those are incorporated in the viscoelastic polymers. In order to address this issue, the phase pure rod-shaped nanocrystalline hydroxyapatite (HAp) powders with varying particle sizes and shapes were synthesized by a one-pot hydrothermal method without any regulatory surfactant at an initial solution pH of 9. As-synthesized nanocrystalline HAp particles (0�5 wt) were incorporated into 15 wt pre-cross-linked gelatin methacryloyl (GelMA) hydrogel matrix to fabricate a predesigned scaffold architecture using a custom-made 3D bioprinter. The printing parameters (nozzle diameter, extrusion pressure, and printing speed) were optimized for each composition. The biophysical properties (uniaxial compression behavior, swelling ratio, and in vitro degradation) of the composite hydrogel scaffolds were critically analyzed to unravel the role of nano-sized HAp addition. The compression strength and modulus were substantially improved, while the rate of water uptake and bio-enzymatic degradation significantly reduced with HAp content. We propose that the inorganic�organic nanocomposite hydrogel could be efficiently assembled to formulate a potential bioink for 3D bioprinting applications toward tissue regeneration. © 2021 The American Ceramic Society

Zirconia has been prepared by exothermic synthesis from solutions, using nitrates and a glycine–urea reducing agent. The phase composition of the synthesis products and the relationship between the zirconia polymorphs have been determined as functions of the amount and nature of the stabilizing oxide and the heat treatment temperature. The addition of 5% calcium and yttrium has been shown to ensure the preparation of a material with partial stabilization of tetragonal zirconia (50–70%) or complete stabilization of the tetragonal phase. The synthesized zirconia consists of flaky macroparticles of various sizes, which in turn consist of rounded nanocrystalline particles up to 100 nm in size. The crystallite size is 10–20 nm.

An excellent photocatalyst must have narrow band gap value, broad absorption range and high electrical conductivity. The co-precipitation route was followed to synthesize copper substituted manganese ferrite nanoparticles because the co-precipitation is a facile, short and easy to handle method. The nanocomposite of copper substituted manganese ferrite with rGO was synthesized by sonication method. The graphene was used for composite synthesis because of its extraordinary properties such as chemical stability, high transparency, large surface area, high electron transfer ability. Graphene can also improve catalytic acitivity of spinal ferrites. X-ray diffraction (XRD), Raman spectroscopy, and field emission scanning electron microscopy (FESEM) were employed to confirm the structural, spectral and morphological aspects of prepared nanomaterials and their composites with rGO. XRD confirmed face centered cubic (FCC) crystal structure. The appearance of relative broad peaks estimated the formation of nanocrystalline size of synthesized samples. SEM images showed that the nanoparticles have spherical morphology. Furthermore, rGO sheets can be clearly seen in SEM images of composite material. It was investigated that electrical conductivity of MnF2O4 was increased by the substitution of metal cations such as copper. Current – voltage measurements were carried out at room temperature and confirmed the enhanced conductivities of copper doped manganese ferrite and its rGO based nanocomposite. These photocatalysts were used for the degradation of methylene blue (MB) dye and Mn0.9Cu0.1Fe2O4/rGO nanocomposite showed great activity in photocatalysis experiment with 77% degradation efficiency. This increment in photocatalysis was found to be due to synergistic effect of ferrite material and rGO sheets, which increases the electrical conductivity and decreases the photoexcited electrons-holes pair recombination of composite materials.

Cu2ZnSnS4 (CZTS) thin films deposited on glass substrate using spray pyrolysis technique were irradiated by 200 MeV Xe ions at different fluences. The effect of high-density electronic excitations on the properties of CZTS thin films has been examined using UV–visible spectrophotometry for optical properties, X-ray diffraction and Raman spectroscopy for structural properties. A pronounced blue-shift in the transmittance spectra edges and bandgap widening up to 2.05 eV were observed as the irradiation fluence increased up to 5 × 1013 ions/cm2. Although CZTS crystallinity gradually deteriorated and crystallite size reduced to 16 nm, total amorphization of the films has not been reached even for the highest fluence. Latent track radius of 3.7 nm was determined experimentally from XRD measurements, in reasonable agreement with the inelastic thermal spike model, which predicts the transition of solid CZTS to molten phase leading to the formation of latent tracks. The possible reasons for the observed blue-shift were carefully discussed in the light of previous findings in literature, and finally was ascribed to the contribution of multiple factors such as quantum confinement effect and annihilation of localized defect bands.

Sedovite, U4+(Mo6+O4)2·nH2O, is reported as being one of the earliest supergene minerals formed of the secondary zone. The difficulty of isolating enough pure material limits studies to techniques that can access the nanoscale combined with theoretical analyses. The crystal structure of sedovite has been solved and refined using the dynamical approach from three-dimensional electron diffraction data collected on natural nanocrystals found among iriginite. At 100 K, sedovite is monoclinic a ≈ 6.96 A, b ≈ 9.07 A, c ≈ 12.27 A, and V ≈ 775 A3 with space group C2/c. The microporous structure presents a characteristic framework built from uranium polyhedra and disordered Mo pyramids creating pore hosting water molecules. To confirm the formula U4+(Mo6+O4)2·nH2O, the possible presence of a hydroxyl group that would promote Mo5+ was tested with density functional theory (DFT) computations at the ambient temperature. DFT predicts that sedovite is a ferromagnetic insulator with a fundamental bandgap of Eg ∼ 1.7 eV with its chemical and physical properties dominated by U4+ rather than Mo6+. The structural complexity, IG,tot, of sedovite was evaluated in order to get indirect information about the missing formation conditions.

Nanocrystalline powders of alkali metal titanates were prepared using titanium tetraisopropoxide and alkali metal salts by a sol–gel method. The influences of the kinds of alkali metal salts and heating temperature on the reaction of the titanium precursor compounds with the alkali metal salts, its phase transition, and crystal growth were investigated by thermal analyses, XRD measurement, and SEM observation in order to prepare lithium, sodium, and potassium titanates at relatively low temperatures. The amorphous titania gel or its product, very small titania crystals, as an intermediate phase reacted with the alkali metal salts at around 500–600 °C while it was still highly active and formed alkali metal titanate nanoparticles before forming the stable titania crystals. It is important that the active amorphous titania gels react with the dispersed alkali metal salts at a temperature as low as possible in order to form the alkali metal titanate nanocrystals.

In the reported work, ZnxFe2O4:Cu2+1−x nanoparticle (CZF NPs) was successfully synthesized from fabrication of copper (Cu2+) doped ZnFe2O4 NPs by a facile one-pot green (Aegle Marmelos extract) assisted combustion approach. The structural characterizations were investigated by specific spectral techniques; Powder X-Ray diffractometer (PXRD) confirms the formation of spinel cubic nanocrystalline structure with crystallite size in the range 20–25 nm. The porous with spongy like structure morphology was noticed by Scanning electron microscope (SEM). The photocatalytic performance of CZF NPs (7 mol%) was examined by observing their potential role in photodegradation of Rhodamine B (Rh-B) dye (94%) under irradiation of UV–Visible light. Electrochemical study was conducted by graphite assisted with CZF electrode paste in 0.1 M KCl electrolyte and performed as an excellent mechanism of charge–discharge supercapacitor nature with high responses towards the electrochemical sensor action for Mifepristone-Misoprostol.

In this research, the effect of calcium oxide (CaO) nanocrystalline particles filled ethylene propylene diene monomer (EPDM) rubber composites is investigated, at different weight percentages (1.0, 2.0, 4.0, and 8 wt%) of CaO nanocrystalline particles using two methods of mixing. In one case conventional mixing on twin roll-mill was used, in the other case ultrasonic mixing as a pre-mixing was applied. CaO particles are synthesized by the precipitation method. The average crystallite size of CaO is 100 ± 20 nm. Adding CaO nanocrystalline particles increases the thermal stability of EPDM and the glass transition temperature. The hardness of EPDM rubber gradually increases with increasing the amount of CaO particles, the maximum hardness 64.2 observed in 8 wt% of CaO particles for both cases almost 26% higher than neat EPDM. Tensile strength decreases, while the maximum % modulus of the ultrasonic mixed sample was 1.48 MPa which is 24% higher than EPDM.