Nano

Corrosion has been the foremost factor affecting the longevity of metals and alloys since ages. It can be thought of as the force of nature which strives to bring the refined form of elements back to their original state. However, human applications are essentially based on refined forms of elements, thereby creating the need for corrosion protection. Corrosion prevention methodologies span between coatings, inhibitors, sacrificial anodes. Coatings have seen maximum utility due to their simplicity and low cost. Researchers are on the lookout of a durable, environment-friendly, cheap coating. Graphene, a carbonaceous material is a new found interest delivering optimistic results. It carries the advantage of being a 2D material, whereby thin coatings with superior quality can be achieved. Additionally, its chemical inertness has proven to be a useful characteristic. On similar lines, electrophoretic deposition (EPD) is low cost and simple technique which has attracted the attention of researchers. It has been used to deposit colloidal solutions onto suitable substrates, mostly ceramics. The significance is growing steadily owing to its capability in producing thin films, nanomaterials and composite coatings. This paper highlights the use of graphene through EPD for synthesis of anti-corrosive coatings.

Nickel pyrophosphate is very popular material having applications in energy storage devices as well as supercapacitors. In this study, a surfactant-mediated approach was adapted to synthesis nickel pyrophosphate nanoparticles. The prepared material was subjected to structural, optical, electrical and electrochemical property studies. Peak broadening in the powder XRD pattern confirmed the nanostructured nature and monoclinic structure of pure $\alpha$-Ni₂P₂O₇ nanoparticle with unit cell parameters of $a=13.09$ $\underset{\AA }{\overset{}{´}}$, $b=8.05$ $\underset{\AA }{\overset{}{´}}$, $c=8.974$ $\underset{\AA }{\overset{}{´}}$, $\alpha =90.00$, $\beta =104.94$, $\gamma =90.00$. Pure $\alpha$-Ni₂P₂O₇ samples calcined at 300^∘C, 600^∘C, 900^∘C show monoclinic structure. The average crystallite size and the internal strain were evaluated using Scherrer’s formula and Williamson–Hall (W-H) respectively. The TEM analysis confirmed the particle size in the range of 5–10nm for Ni₂P₂O₇. Presence of symmetric and asymmetric stretching vibrations of P–O–P and PO₃ was determined by FT-IR spectroscopy. The spectral range of 210–1200nm was employed by the UV-NIR absorption spectroscopy, and the energy band gap calculated from Tauc’s plot is found to be 5.38eV for pure Ni₂P₂O₇. The EDAX analysis confirmed the elemental composition. The TGA analysis reveals that the sample becomes anhydrous and remain stable beyond 600^∘C. The higher dielectric constant observed for the sample is promising for semiconductor, DRAM memory devices and ceramic capacitors. The a.c. conductivity increases with increasing frequency and follows Jonscher’s Power law. On the basis of Jonscher parameters, small polaron QMT conduction model is prevailing. The cyclic voltammetry study was carried out to ascertain the application potential for supercapacitors.

Lithium-rich manganese-based oxides have become one of the widely studied cathode materials for lithium-ion batteries due to their high-energy density, relatively low price and environmental friendliness. Herein, we propose a simple self-template route to prepare ${\text{Li}}_{1.2}$${\text{Mn}}_{0.54}$${\text{Ni}}_{0.13}$${\text{Co}}_{0.13}$O₂ nanorods using rod-like Mn₂O₃ as templates. Besides, the effect of calcination temperature on the morphology and electrochemical properties of the electrode materials was investigated. ${\text{Li}}_{1.2}$${\text{Mn}}_{0.54}$${\text{Ni}}_{0.13}$${\text{Co}}_{0.13}$O₂ nanorods as the cathode exhibit initial capacity of 251.4 mAh g^t1 at 0.1 C and capacity retention rate of 67.9% after 200 cycles, which can be attributed to the enhanced layered structural stability, lower charge transfer resistance and shorter lithium-ion transport pathway.

Divers spectroscopy techniques and advances imaging are elucidated when employing light in a controlled manner. One of the features of the light focusing fields is the localized surface plasmon resonance (LSPR). In this paper, we study the LSPRs for different arrangements of palladium (Pd) nanostructures with respect to light polarization in the visible and near-infrared regions. The extinction cross-section spectrum of asymmetric nanostructures is measured using far field spectroscopy technique and is calculated using Finite Element Method (FEM). The spectra of the nanostructures various arrangements recorded from the two methods are in very good agreement. Depending on the light polarization, the nanostructures produce strong plasmonic coupling. This is represented by the induction of dipole and quadrupole LSPR modes. A clear enhancement of the extinction spectrum has been evidenced by increasing the number of particles of nanostructures. The main advantage of the transition metallic nanostructures of different arrangements lies in the generation of a highly enhanced electromagnetic field accompanied by a redshift of LSPR spectrum that can be exploited in diverse applications.

Silver nanoparticles (AgNPs) are considered an appropriate approach to treat the leishmaniasis in terms of the toxicity and resistance of current anti-leishmanial drugs. This study aimed to prepare stable AgNP and their apoptotic effects on the metabolic activity of Leishmania major. AgNPs were prepared with a green synthesis method using Z. multiflora Boiss ($Z.M)$ extract as a reducing and carboxymethylcellulose (CMC) stabilizer agent. The formation and colloidal stability of AgNPs were shown using ultraviolet-visible absorption spectroscopy during an 80-day period. The average diameter of $45.2\pm 23.5$ nm and the surface charge of $-42\pm 1$ mv were obtained for AgNPs. Furthermore, the toxicity and apoptotic values of AgNPs on Leishmania major were evaluated by MTT assay and flow cytometry, compared with ${\text{Glucantime}}^{\text{®}}$ (meglumine antimoniate) as the current standard medication for leishmaniosis. The results indicated that $Z.M$ extracts coated AgNPs (Z.M@AgNPs) reached ${\text{IC}}_{50}$ at a 100 $\mu$g/mL concentration, while ${\text{Glucantime}}^{\text{®}}$ reached this point at a concentration of 4000 $\mu$g/mL. The flow cytometry data revealed that the primary mechanism of death in the promastigotes was apoptosis (35.44% for AgNPs and 32.69% for ${\text{Glucantime}}^{\text{®}}$). The present findings suggest that Z.M@AgNPs are superior therapeutic agents than ${\text{Glucantime}}^{\text{®}}$ as the positive control group for leishmaniasis treatment. However, further advanced studies are needed to confirm these results.

A turn-on fluorometric probe is designed for the determination of ascorbic acid (AA) based on the inner filter effect (IFE) between CaF₂:${\text{Yb}}^{3+}$, ${\text{Er}}^{3+}$ upconversion nanoparticles (CaF₂:${\text{Yb}}^{3+}$, ${\text{Er}}^{3+}$ NPs) and the oxidized 3, $3^{\prime }$, 5, $5^{\prime }$-tetramethylbenzidine (oxTMB). The colorless TMB can be oxidized by H₂O₂/${\text{Cu}}^{2+}$ to blue oxTMB. Under 980 nm photoexcitation, CaF₂:${\text{Yb}}^{3+}$, ${\text{Er}}^{3+}$ NPs can emit red light, which can be absorbed by the blue oxTMB, leading to the fluorescence quenching at 657 nm. As AA can reduce the blue oxTMB to colorless TMB, the fluorescence at 657 nm can be recovered with the addition of AA, which can accomplish the detection towards AA. The linear detection range of AA is from 1 to 30 $\mu$M, and the limit of detection (LOD) of AA is 0.1 $\mu$M.

Inorganic micro-nanomaterial is an excellent choice for constructing the functional surface of liquid repellency. In this work, $\gamma$-AlOOH micro-nanostructure with special morphology was prepared by a simple hydrothermal method using common feedstock. Stearic acid was used as a hydrophobic modifier to obtain the superhydrophobic and oleophobic surface with good durability. Stearic acid molecule and $\gamma$-AlOOH are connected by both physical and chemical adsorption, which is more conducive to improve structure stability. The water contact angle and diiodomethane contact angle of the film could reach up to $162.8^{\circ }$ and $134.8^{\circ }$, respectively. Both morphology and composition of $\gamma$-AlOOH are affected efficiently by the valence anions in hydrothermal reaction. Reaction conditions including reaction time, substrate and surfactant have a great influence on the morphology and wetting performance of $\gamma$-AlOOH structure. The surface hydroxyl group on substrate surface plays a guidance and orientation role in the growth of micro-nanostructure. The surface wettability depends on its roughness. The superhydrophobic and oleophobic $\gamma$-AlOOH surface prepared with a simple method and cheap raw material has broad application prospect.

A metal and metal oxide quantum dot (QD) was synthesized by a simultaneous oxidative reduction method. Aniline was polymerized both in the presence and absence of o-toluidine (OT) as a co-monomer and in the presence of peroxomonosulfate (PMS) as a free radical initiator in N-methyl pyrrolidone (NMP) medium at 0–5^∘C for 3 h under vigorous stirring condition. The metal or metal oxide bulk powder was used as source material for the generation of QD. At the end of the reaction a dark green colored polymer was formed, filtered and dried at 110^∘C for overnight. The dried polymer was subjected to HR-TEM analysis. The size and shape of the crystals formed were noted and compared with the literature reports.

By using the first principles calculations, we study the structural and electronic properties of zinc oxide (ZnO) bilayers. Initial ZnO bilayer has a planar structure, which is different from bulk ZnO. Another kind of twist ZnO bilayer is designed by rotating 60° on the basis of ZnO bilayer structure with a Zn/O atom as the axis. Both the bilayers have stable structure and high symmetry. As the interlayer distance increases, the interaction of the upper and the lower layers will weaken in both the bilayers. It is Zn atom but not O atom that plays a key role in the interlayer interaction, which has been confirmed by Mulliken charge and density of states results. The band gap of the bilayers can be tuned by translation motion, and ZnO twist bilayer shows a better performance than the initial bilayer in this study. Combining the two factors (interlayer distance and twist angle), ZnO bilayers are very hopeful to be utilized in 3D joints of nanoelectronic devices. Our results provide a detailed understanding of the structural and electronic properties of ZnO bilayers and help to predict the performance of ZnO-based two-dimensional nanoelectronics and nanocomposites.