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This novel study is crucial in understanding the intriguing electronic, structural and chemical properties of special double perovskite compounds, Ba2SmRuO6 and Sr2SmRuO6, for their applications as “Spintronics based devices”.

Shilpy Bhullar,1 Navdeep Goyal,1 Shikha Gupta2 1Department of Physics, Centre of Advanced Study in Physics, Panjab University, Chandigarh, 160014, India; 2Department of Physics, Goswami Ganesh Dutta Sanatan Dharma College, Chandigarh, 160032, IndiaCorrespondence: Shikha Gupta, Department of Physics, Goswami Ganesh Dutta Sanatan Dharma College, Sector-32c, Chandigarh, 160032, India, Email shikhagupta16@gmail.comIntroduction: Titanium dioxide nanoparticles (TiO2 NPs) have shown tremendous potential in targeted drug-delivery applications. Among various mechanisms, magnetically guided transport of drugs is one such technique for the said purpose. TiO2 NPs being diamagnetic or sometimes exhibiting very weak ferromagnetism can be modified by treating them with suitable magnetic materials.Methods: Rutile TiO2 NPs were synthesized and doped with Iron Supplement FericipXT and rare-earth metals like cerium, erbium and neodymium via sol–gel technique. FericipXT-coated rutile TiO2 NPs were synthesized in three different core-shell ratios (1:3, 1:1 and 3:1). The resulting samples were characterized via X-ray Diffraction (XRD), Vibrating Sample Magnetometer (VSM) and High-Resolution Transmission Electron Microscopy (HR-TEM).Results: XRD of FericipXT-doped TiO2 NPs showed a rutile phase for 1% and 3% doping; however, only a small fraction of the maghemite phase was obtained for 5% doping. The XRD plots of Ce-doped, Er-doped and Nd-doped TiO2 NPs showed a variety of phases of TiO2 NPs (such as anatase/rutile/mixed) along with the oxide phases of the corresponding rare-earth metal. The presence of various iron titanium oxides and iron oxides was found in core-shell NPs. HR-TEM images confirmed the formation of 1:3, 1:1 and 3:1 core-shell TiO2 NPs. VSM studies showed that the resulting NPs depicted magnetism in the form of superparamagnetism, ferromagnetism and even paramagnetism.Discussion: The doping to 3% does not affect the original phase of the resulting TiO2 NPs as depicted from the XRD; however, a doping of 5% and more resulted in extra phases corresponding to the dopant added. FericipXT was loaded over TiO2 NPs in amorphous form. Among all the samples synthesized, FericipXT-coated TiO2 NPs demonstrated the best magnetic ability. It was deduced that coating with a magnetic material drastically improves the magnetic character of the host NPs.Keywords: magnetically-guided drug delivery, drug delivery, rare-earth metals, iron supplement, TiO2 nanoparticles, superparamagnetism, paramagnetism, ferromagnetism

We are presenting here fabrication of silicon (Si) nanowires (NWs) arrays by using Si (1 0 0) wafer as substrate, by metal assisted chemical etching (MACE) method. The Si-NWs growth on the Si wafer has been done by using etching time of 45 min in etching solution of hydrogen fluoride and hydrogen peroxide. X-ray diffraction (XRD) has been used for the structural analysis of NWs to estimate the crystalline size, micro-strain, dislocation density of fabricated nanostructures. The surface morphology of Si-NWs array has been studied through field effect scanning electron microscopy (FE-SEM). The optical properties like energy band gap of fabricated Si-NWs has been carried out through UV–Vis diffuse reflectance spectroscopy (UV DRS) and photoluminescence (PL) spectroscopy.

Recently invented hydroelectric cell (HEC) is emerging as a better alternative for green electrical energy devices. HEC is fabricated as to generate electricity via splitting of water into H3O+ and OH− ions without releasing any toxic product. In iron oxides, Hematite (α-Fe2O3), magnetite (Fe3O4) and maghemite (γ-Fe2O3) nanoparticles HEC are recently reported for their remarkable electrical response by splitting water molecules. Fe3O4 HEC 4.8 cm2 surface size has delivered 50 mA short circuits current. Li ions into Fe3O4 stabilize electrical cell response to 44.91 mA with open-circuit voltage 0.68 V. Maghemite based HEC delivered a maximum short circuit current 19 mA with emf 0.85 V using water 200 μL. Maximum off-load output power 27.6 mW has been delivered by 4.84 cm2 area hematite-HEC which is 3.52 times higher with 7.84 mW power as generated by Li-Mg ferrite HEC. Maximum electrical power 16.15 mW delivered by maghemite HEC is 0.58, 0.42 times lower than respective magnetite, hematite HECs. In more applicability of iron oxides, the multiferroic nanocomposites of BaTiO3 with 85% CoFe2O4 has been shown maximum short circuit current 7.93 mA and 0.7 V emf by sprinkling few drops of water on HEC surface. Li0.3Ni0.4Fe2.3O4 and Mg0.8Li0.2Fe2O4 HECs also have some remarkable results for green energy generation.

Instant synthesis of Zinc Oxide (ZnO) nanostructures has been reported here by simple mixing of zinc precursor with sodium hydroxide base at pH = 7. This method can be useful for treating bulk effluents saving time and cost. In order to make comparative study at same pH, ZnO nanostructure has been prepared by conventional mixing method also. Crystal purity of ZnO nanostructure has been verified with X-ray diffraction technique whereas morphological information is studied with Field Emission Electron Microscope. Optical properties are invesigated with help of UV–vis spectroscopy. Prepared samples are investigated as photo catalyst for Methylene Blue (MB) dye degradation using natural sunlight. The 95% & 70% dye degradation values have been observed for instant and conventional method respectively. Novelty of reported instant synthesis over conventional techniques is that it has minimum preparation time, high yield for bulk production and cost effectiveness due to minimum use of apparatus and reusability of catalyst due to larger particle size. This study really has features like economical, effectiveness as well novelty in approach.

Here, by varying the etching time of Si wafer with metal-assisted chemical etching process, we have formed the vertically aligned silicon nanowire (VA-SiNW) by etching the Si wafer for the duration of 40 min with metal-assisted chemical etching method. In this study Field-effect scanning electron microscopy has been used for the characterization of VA-SiNW (FESEM). Here the etching duration of 40 min has been used, the band gap modification has been analyzed by the use of photoluminescence spectroscopy. The study of photoluminescence spectroscopy (PL) and XRD offers proof of our findings and appears as supporting information. These 1-D nanostructures are quite influential in sensing, biological applications anti-reflection coating (ARC) properties and have broad use in electronic field.

Nanoparticles (NPs) with sizes ranging from 2 nm to 1 μm find various applications in the field of theranostics. Moreover, if eco-friendly methods are opted for the synthesis of biocompatible and less toxic NPs, then that's a huge success. Titanium dioxide nanoparticles (TiO2 NPs) have been vigorously studied for their use in medical implants, photodynamic therapy, drug delivery, biosensing and as antimicrobial agents. The present study reports the green-synthesis of TiO2 NPs for the first-time using extracts of black pepper (Piper nigrum), coriander (Coriandrum sativum) and clove (Syzygium aromaticum). All three samples of TiO2 NPs were synthesized via a modified sol–gel method under similar environmental conditions. Similar treatments were given to the samples. The procedure adopted for the synthesis ensures the use of non-toxic materials, no production of toxic by-products and rapid synthesis of the TiO2 NPs. The NPs were characterized by X-ray diffraction, high resolution-transmission electron microscopy, energy dispersive spectroscopy, field emission scanning electron microscopy and selected area electron diffraction which confirmed the formation, morphology, crystallinity and size of the TiO2 NPs. These characterizations displayed the similarity index of all three samples. However, photoluminescence and vibrating sample magnetometer studies highlighted the differences among the three samples. All three samples of NPs obtained had a size range of 5–20 nm. Further, the findings showed that different plant extracts result in TiO2 NPs with moderately different characteristics. Furthermore, the samples were analysed for their drug-encapsulation efficiency using UV-visible spectrophotometry. Among all three samples, the NPs synthesised using black pepper exhibited the maximum encapsulation efficiency. The study concludes that the plant's bio-profile is responsible for bringing about changes in the traits of the resulting nanoparticles. Thus, the extracts from different plants have the ability to manipulate the properties of the synthesized NPs. These findings can help to understand the role and importance of the plants in synthesizing NPs for biomedical applications. A further detailed study in this field can help researchers to understand the influence of the plant's biochemistry in shaping the NPs.

Targeted drug delivery is one such precision method of delivering medication inside the human body which can vanquish all the limitations of the conventional chemotherapeutic techniques. In the present study, two types of nanoparticles (NPs) were chosen for the in-vitro pH-responsive release study of the drug, Imatinib, namely anatase Titanium Dioxide nanoparticles (TiO

In this paper, we report the existence of defect induced intrinsic room-temperature ferromagnetism (RTFM) in Cu doped ZnO synthesized via a facile sol–gel route. The wurtzite crystal structure of ZnO remained intact up to certain Cu doping concentrations under the present synthesis environment as confirmed by the Rietveld refined X-ray diffraction pattern with the average crystallite size between 35 and 50 nm. Field emission scanning electron microscopy reveals the formation of bullet-like morphologies for pure and Cu doped ZnO. Diffuse reflectance UV-vis shows a decrease in the energy band gap of ZnO on Cu doping. Further, these ZnO samples exhibit strong visible photoluminescence in the region of 500–700 nm associated with defects/vacancies. Near-edge X-ray absorption fine-structure measurements at Zn, Cu L3,2- and O K-edges ruled out the existence of metallic Cu clusters in the synthesized samples (up to 2% doping concentration) supporting the XRD results and providing the evidence of oxygen vacancy mediated ferromagnetism in Cu : ZnO systems. The observed RTFM in Cu doped ZnO nanostructures can be explained by polaronic percolation of bound magnetic polarons formed by oxygen vacancies. Further, extended X-ray absorption fine-structure data at Zn and Cu K-edges provide the local electronic structure information around the absorbing (Zn) atom. The above findings for ZnO nanostructures unwind the cause of magnetism and constitute a significant lift towards realizing spin-related devices and optoelectronic applications.

Despite the crowd of germanium (Ge), antimony (Sb) and tellurium (Te) based chalcogenide alloys discovered since 1960, most of the research has been focussed on Ge2Sb2Te5, Ge1Sb2Te4 and Ge1Sb4Te7. ...

Advances in material science and nanotechnology permits combination of new materials with tuned physical, chemical and optical properties with high effectiveness. These multifunctional materials has wide areas of application in gas sensors/separators, membranes, catalysis etc. Air and water quality monitoring, food-safety, medicine, defense are the important fields require a novel technology for fabricating a device having desirable characteristics such as low power requirements, selectivity, sensitivity and stability. Metal-Organic Framework (MOF) is a widely studied porous nanomaterial due to its exceptional degree of flexibility for both organic/inorganic ligands in the structure, which differentiate it from other organic nanostructure. The known strategies used in MOF synthesis, includes different synthesis routes, precursor concentration, temperature and pressure plays a precious role in view of the above required applications. This review article compiles and recounts the extending traits and behavior of MOF, synthetic route, nucleation and growth corresponding with applications, introduction to its structure and various results analysis in comprehensive way. The detailed discussion of MOF nanomaterial as chemical sensor and the historical background of porous nanomaterial in solid state chemistry is presented.

In this study, X-ZnO/ZnO/Si(100) (X = Co, Ni and Cu) bilayer structure is fabricated using low energy ion implantation technique. Five different fluences 1 × 1015, 5 × 1015, 1 × 1016, 2.5 × 1016 and 5 × 1016 ions/cm2 with 100 keV ion-beam energy were selected in order to implant the ions up to the depth of ≈44 nm as calculated through Stopping Range of Ion in Matter and Transport Range of Ions in Matter software. Structural modification was investigated by high resolution X-ray diffraction measurements in ZnO bilayer system. An observed systematic 2θ shift in (002) peak with increasing fluence implies increased density of implanted metal ions in ZnO matrix revealing the substitution of implanted ion at Zn-site. The mechanism of bilayer formation by ion-beam implantation technique has been discussed for metal-ions by investigating their interface properties. Atomic force microscopy reveals the morphological modification after ion implantation. Near-edge X-ray absorption fine-structure (NEXAFS) measurements at metal K- and L3,2-edges have been used to investigate the nature of implanted ions in terms of their valance state and local electronic environment. Further, O K-edge NEXAFS measurement for Ni-ZnO/ZnO/Si bilayer is highly sensitive to incident beam angles whereas no spectral change is seen for Zn L-edge measurements. The magnetic measurements were performed via vibrating sample magnetometer that showed the films are ferromagnetic at room temperature. The origin of ferromagnetism has been understood through defect mediated bound magnetic polaron model. Further, perpendicular magnetic anisotropy is also observed for Ni-ZnO/ZnO/Si bilayer structure at room temperature, which is correlated with the angle dependent O K-edge NEXAFS measurements. Fabrication of ZnO bilayer via ion implantation and investigation of above properties may prove useful in spin related and optoelectronic applications.

The presence of impure phases affects thermoelectric properties of material by introducing two types of conduction (n and p type) in a thermoelectric system. This manuscript focuses on investigating the influence of impurity phases on structural and electrical properties of solvothermal synthesized CoSb3 system. X-ray diffraction and Rietveld analysis unveiled that incrementing the synthesis temperature and duration, increases the probability of attaining a pure phase CoSb3 skutterudite. The crystallite size of samples obtained from Sherrer's formula is in the range 43–45 nm. The Rietveld refinement further showed that percentage of cubic CoSb3 phase is highest i.e. 98% having synthesis profile of 260 ∘C for 48 h. In contrast, 24 h synthesized sample at 260 ∘C shows the presence of impure phase Sb2O3 rods of micron size and FESEM analysis also indicated that average particle size varies from 56 to 66 nm and shows spherical morphology. The Hall measurement of the samples revealed carrier concentration and mobility of the order of 10 17 − 18 cm−3 and 0.5–10 cm2V−1 s−1, respectively at room temperature. The electrical conductivity, from I-V measurement was around ≈ 121 S m−1 in purest synthesized sample. These investigation generalizes the effect of impurity phases on the figure of merit and optimizing for efficient thermoelectric system.

Cobalt ferrite and silver doped cobalt ferrite, AgxCo1−xFe2O4, (x = 0, 0.005, 0.01, 0.02) nanoparticles were synthesized through sol-gel auto-combustion technique via chemical and green synthesis (using the extract of tulsi seeds(Ocimum sanctum) and garlic cloves(Allium sativum)). Systematic characterization by XRD, FTIR, FE-SEM and EDX has been performed to study structural, morphological and magnetic behavior of the prepared samples. XRD confirms that the prepared samples are crystalline and have a cubic (inverse spinel) structure. Absorption bands have been studied using FTIR that further confirms the formation of single phase spinel crystal structure having two sub-lattices (Td and Oh). FE-SEM micrographs reveal the formation of cubic and encapsulated type structure in case of chemical and green synthesis respectively. EDX confirms the presence of all the required elements in the respective stoichoimetric ratios. Magnetic measurements through VSM at room temperature show that the magnetic saturation values for samples obtained using tulsi seed extract mediated synthesis and chemical synthesis are much higher than those obtained using garlic extract. The antibacterial activity of all the prepared samples against gram positive and gram negative strains were investigated and a modified mechanism of action for the antibacterial activity is proposed.

Nanoparticles (NPs) with sizes ranging from 2 nm to 1 μm find various applications in the field of theranostics. Moreover, if eco-friendly methods are opted for the synthesis of biocompatible and less toxic NPs, then that's a huge success. Titanium dioxide nanoparticles (TiO

There is a plethora of factors which affect the synthesis of Titanium Dioxide (TiO2) nanoparticles (NPs). There is a great deal of benefits if we know how to optimize different factors to tune the properties of NPs. Out of many factors like precursor, pH, mode of synthesis, time, pressure, etc. temperature and reagents play a great role in modulating NPs. Even though, many researchers are making nanoparticles by following different approaches, not much is known about how and why do these factors actually affect the NPs during synthesis. The present review highlights the works where temperature and nature of reagents or solvents pose a significant contribution in the manufacturing of stable nanoparticles. Moreover, possible explanations would be put forth describing the observed behaviour.

The optimization of secondary phase in thermoelectric(TE) materials can {helps in improvisation of material's efficiency}. Being a potential {contender} for lower temperature TE application, bismuth telluride(Bi$_2$Te$_3$) nanoparticles were synthesized via different routes and profiles to optimize their pure single phase. Systematic characterizations were performed with the help of X-ray diffraction (XRD), Rietveld refinement and field effect-scanning electron microscopy(FE-SEM) for structural and morphological behavior, while TE properties such as Seebeck coefficient, electrical conductivity and power-factor were measured for the purest sample chosen. Rietveld refinement in the XRD pattern of the samples revealed that only a small amount ($\sim$ 1.6\%) of Bi$_2$Te$_3$ was formed in co-precipitation method, while the hydrothermal technique increases this phase with increment in synthesis duration. This work focused on the phase evolution of Bi$_2$Te$_3$ with increasing synthesis duration time at constant temperature and vice-versa. XRD and Rietveld refinement revealed that the hydrothermal technique (150 $^\circ$C for 48 hours) can synthesize purest samples (84\% Bi$_2$Te$_3$ phase in this case). {FE-SEM and Energy Dispersive X-ray analysis unveiled that the impure phases in the system {were} quantitatively reduced, and it supported by decline in atomic percentage of oxygen from 37\% to 11\%, in addition to this, it was also found that particle size was also decreased with increase in temperature.} The observed electrical conductivity of the chosen sample is $\sim$20 times greater, while Seebeck coefficient is $\sim$3 times lower than that of pure Bi$_2$Te$_3$ phase. The detailed analysis has generalized the growth mechanism in Bi$_2$Te$_3$ phase evolution by the diffusion of Bi into Te nanorods to fabricate hexagonal Bi$_2$Te$_3$., 10 pages, 17 figures, 4 tables

Plasmonic nanostructures are of immense interest of research due to its widespread applications in microelectronics, photonics, and biotechnology, because of its size and shape-dependent localized surface plasmon resonance response. The great efforts have been constructed by physicists, chemists, and material scientists to deliver optimized reaction protocol to tailor the size and shape of nanostructures. Real-time characterization emerges out as a versatile tool in perspective to the optimization of synthesis parameters. Moreover, in the past decades, radiation-induced reduction of metallic-salt to nanoparticles dominates over the conventional direct chemical reduction process which overcomes the production of secondary products and yields ultra-high quality and pure nanostructures. Here we show, the real-time/in-situ synthesis and detection of plasmonic (Au andAg) nanoparticles using single synchrotron monochromatic 6.7 keV X-rays based Nano-Tomography beamline. The real-time X-ray nano-tomography of plasmonic nanostructures has been first-time successfully achieved at such a low-energy that would be leading to the possibility of these experiments at laboratory-based sources. In-situ optical imaging confirms the radiolysis of water molecule resulting in the production of $$e_{aq}^-,\,OH^\bullet ,$$ e aq - , O H ∙ , and $$O_2^-$$ O 2 - under X-ray irradiation. The obtained particle-size and size-distribution by X-ray tomography are in good agreement to TEM results. The effect of different chemical environment media on the particle-size has also been studied. This work provides the protocol to precisely control the size of nanostructures and to synthesize the ultrahigh-purity grade monodisperse nanoparticles that would definitely enhance the phase-contrast in cancer bio-imaging and plasmonic photovoltaic application.

The bulk chalcogenide (Se80Te20)100−xZnx (2 ≤ x ≤ 6) alloys are prepared using melt quenching technique and electronic transport properties are studied in the frequency range 50 Hz–500 KHz and temperature range 400–520 K. The sharp peaks observed in X-ray diffraction pattern indicate the polycrystalline nature of prepared compositions. The measured dielectric properties and a.c. conductivity reveal the significant influence of Zn doping on the properties of the Se-Te matrix. The a.c. conductivity obeys Jonscher power law as ∼ ωs (s

Magnetoelectric (ME) nanocomposites is a topic of intensive research due to their superficial potential in spintronic applications. In the present work, the magnetic field controlled electrical polarization is studied in hydrothermally synthesized multiferroic 0.25BaTiO3-0.75CoFe2O4 (BTO-CFO) nanocomposite. This multiferroic heterostructure is combined ferrimagnetic (CFO) with ferroelectric/piezoelectric (BTO) and achieved strain-mediated ME effect, which can effectively mediate magnetic anisotropy. The X-ray diffraction pattern confirmed polycrystalline phases of spinel CFO and tetragonal BTO, for which the compressive lattice strain is made. The microstructural study has evaluated BTO-CFO nanoparticles formation and the value of d-lattice spacing is calculated. The room temperature magnetic hysteresis is arising which depends on CFO inversion degree, and the change in bond-angle/length along A and B-sites. The ferroelectric hysteresis is measured at room temperature, which changed with applied magnetic field, i.e., the phenomenon of reduction in domain wall pinning related with oxygen vacancies and grain boundaries effect. The magnetic field is also influenced impedance spectra to induce magnetoimpedance effect and the positive value of magnetoresistance is obtained. A giant magnetodielectric coefficient up to −27% is obtained at 1 kOe of field. A strain mediated ME coupling enhancement is obtained.

The induction of charge and spin in diluted magnetic semiconductor ZnO is explored for spintronic devices and its wide direct band gap (3.37 eV) and large exciton binding energy (60 meV) exhibit potential in UV photodetectors. We reported the ferromagnetic and optical properties of pure ZnO, Zn0.97Nd0.03O and Zn0.97Sm0.03O thin films. These thin films were synthesized by a metallo-organic decomposition method and annealed at 500 °C for 7 h. Rietveld refinement of the XRD data results in a wurtzite ZnO structure with Nd, Sm doping. The dopants and nanoparticle size are responsible for wurtzite structural deformation, inducing lattice strain effect, which may influence the band gap energy and high-TC ferromagnetism of ZnO. The average size of ZnO nanoparticles with Nd, Sm doping is 10 nm, confirmed with atomic force microscopy. The Raman spectra confirm the wurtzite structure of ZnO with crystalline quality and lattice defect formation with dopant Nd, Sm ions. A near-band-edge emission due to band gap energy is evaluated with photoluminescence spectra, which also involved multiple visible emissions due to oxygen vacancies. The oxygen vacancies-mediated magnetic interactions impart room temperature ferromagnetism in pure ZnO which is enhanced with Nd, Sm doping. The electron paramagnetic resonance spectra revealed the effects of defects and unpaired electrons responsible for observed room temperature ferromagnetism. The zero field cooling and field cooling magnetic measurements include antiferromagnetic interactions without any spin-glass formation. The observed ferromagnetism also correlates with first principle calculations reported for Nd, Sm-doped ZnO and suggests long-range ferromagnetic ordering attributed to defect carriers. The Nd, Sm doping into ZnO thin films significantly enhances absorption in the UV region and suggests its usability for UV detectors. Under UV irradiation (λ = 325 nm), the value of photocurrent in Nd, Sm:ZnO thin films is highly enhanced for possible use in UV sensors.