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β-Bi 2 O 3 and Ni-incorporated β-Bi 2 O 3 nanoparticles with different Ni incorporating amounts (0, 2, and 4 at. wt. %) were successfully synthesized through a viable hydrothermal process. As-synthesized nanoparticles were analyzed by complementary analytical tools such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDS), UV–visible spectroscopy (UV–Vis), and photoluminescence spectroscopy (PL) for structural, microstructural, compositional, and spectral properties. The photocatalytic performance of synthesized nanoparticles was assessed by subjecting them to visible light irradiation and monitoring the decomposition of rhodamine-B dye. The findings demonstrated that the inclusion of Ni(4%) in β-Bi 2 O 3 nanoparticles significantly enhanced its photocatalytic activity compared to pristine β-Bi 2 O 3 which is desirable for environmental remediation. This improvement may be caused by increased generation of electron-hole (e−-h+) pairs, reduced recombination rate of these pairs, enhanced absorption of visible light, and a decreased band gap energy. To evaluate the specific capacitance characteristics of synthesized electrode materials, cyclic voltammetry, galvanostatic charge-discharge, and electrochemical impedance analyses were conducted. The super capacitance activities of prepared electrode materials were observed in the order of Bi 2 O 3 < Ni(2%)-Bi 2 O 3 < Ni(4%)-Bi 2 O 3. Notably, Ni(4%)-Bi 2 O 3 nanocomposite exhibited higher supercapacitance, which can be attributed to the effective role of appropriate nickel incorporation in Bi 2 O 3. These results suggested that the incorporation of Ni(4%) into β-Bi 2 O 3 to form a nanocomposite showed greater capability as an effective electrode material for advanced energy storage devices, especially supercapacitors. Ni (0,2,4%) incorporated-Bi 2 O 3 nanoparticles were successfully synthesized and characterized through viable techniques. Ni (4%)- Bi 2 O 3 nanoparticles have shown enhanced visible light driven photocatalytic activity against organic dyes for environmental remediation. It also exhibited high supercapacitance desirable for high capacity electrode material employable in supercapacitors. [Display omitted] • Ag NPs-loaded brookite TiO 2 NWs supported on rGO sheets were produced hydrothermally. • Structure and morphology were evaluated by XRD, XPS and SEM/TEM. • Ag–TiO 2 /rGO nanohybrid exhibited an excellent light induced photocatalytic performance. • A suitable schematic mechanism was proposed for photocatalytic degradation of dye. • Ag–TiO 2 /rGO nanohybrid demonstrated fairly high electrochemical electrode material characteristics. [ABSTRACT FROM AUTHOR]

Dissimilar material (Al and steel) tubes have been successfully joined together using magnetic pulse welding technique by setting optimized parameters i.e., discharge voltage and standoff distance. The welded interface has revealed an irregular wavy morphology with melt pockets (max. width ∼20 μm) consisting of intermetallic compound embedded in elemental mixture. High resolution electron microscopy and compositional analysis through energy dispersive x-ray spectroscopy (EDXS) have revealed the formation of 2–3 μm long rod-shaped Fe-Al intermetallic compound. Non-destructive ultrasonic C-scans of the sample welded at 15.5 kV discharge voltage and 1.25 mm air gap have indicated sound welds between the two materials depicting 80% joint integrity while considering the backwall reflection threshold at 50%. The corrosion behaviour at the weld interfaces has been investigated in aqueous solution of 3.5 wt. % NaCl using both potentiodynamic and immersion tests revealing the influence of the intermetallic compound layer on corrosion. [Display omitted] • Non-destructive ultrasonic C-Scan characterization of magnetic pulse welded Al-Steel tubes. • Weld interface consists of 10–20 μm thick melt pockets of Al-Fe intermetallic. • The IMC layer thickness at the interface is directly proportional to the heat input that accelerates the corrosion rate. [ABSTRACT FROM AUTHOR]

The present study was conducted to synthesise aerogel and xerogel solids based on zirconia doped with cobalt using solgel procedure. The obtained nanoparticles (Zr doped Co-NPs) were further characterized with high resolution scanning electron microscopy, energy-dispersive X-ray spectroscopy and Diffuse reflectance spectroscopy. Additionally, the antimicrobial activity of Zr doped Co-NPs was assessed against Gram-positive and Gram-negative pathogenic bacteria. Our results revealed that synthesized Co/Zr aerogels have a regular spherically shaped, heavily aggregated as groups of clusters with nanometric sizes. Regarding the antibacterial properties, synthetized nanoparticles were found to more effective against Escherichia coli and Klebsiella pneumoniae with of inhibition zones reaching 15 mm at a concentration of 35 μg/mL.The same result was registered against Staphylococcus aureus strain at a higher concentration (45 μg/mL). However, no activity was observed against Enterococcus faecalis strain. The varied structure and morphologies of the tested nanomaterials influenced their antibacterial capabilities, since aerogel particles are dotted of spherical form and nanometric size. Whereas xerogels particles are nearly irregular in shape and larger in size. [Display omitted] • Aerogel has bactericide activity against Gram-negative and Gram-positive bacteria. • Xerogel that is completely inactive toward all the tested bacteria. • Aerogel has nano-scale spherical structure facilitating its penetration throw bacterial cell wall. • Xerogel particles have rocky and agglomerated aspect of large particles. [ABSTRACT FROM AUTHOR]

Spinel structured zinc ferrite (ZF) has been green synthesized using microwave-assisted solution combustion method. Toxic free Hibiscus leaves extract was used as a reducing agent in the synthesis process. Rietveld refinement analysis of high-resolution X-ray diffraction (XRD) pattern confirmed that the ZF has cubic spinel structure with the average crystallite size of 10.47 nm. Agglomerated spherical shapes were observed in green synthesized spinel ZF by scanning electron microscope. The estimated average particle size was found to be 11.52 nm by high resolution transmission electron microscopy imaging. The Zn, Fe and O are the main elements present in spinel ZF, analysed from energy dispersion X-ray analysis. Tetrahedral and octahedral lattice sites which are related to Zn–O and Fe–O bonds were identified by Fourier transform infra-red and Raman spectra. The estimated optical energy bandgap of spinel ZF is found to be 2.17 eV using diffuse reflectance spectroscopy. The Vibrating sample magnetometer results showed single domain superparamagnetic nature of spinel ZF at room temperature. In addition, antibacterial properties of spinel ZF were tested using agar dispersion and agar well diffusion methods on gram negative bacteria Escherichia coli DH5α, after 24 h the bacterial growth completely inhibited. [Display omitted] • Spinel zinc ferrite oxide (ZnFe 2 O 4) was successfully green synthesized using Hibiscus leaf extract as a stabilizing agent. • Spinel structure of ZnFe 2 O 4 explained by HR-XRD analysis. • Agglomerated particles are observed in spinel ZnFe 2 O 4. • The estimated optical energy bandgap of green synthesized spinel ZnFe 2 O 4 is 2.17 eV. • The spinel ZnFe 2 O 4 has good antibacterial properties against gram negative E. coli DH5α bacteria. [ABSTRACT FROM AUTHOR]

We present a study of the synthesis and characterization of molybdenum oxide nanostructures produced by laser ablation of solids in liquids (LASL). A high purity molybdenum target was ablated in deionized water using femtosecond laser pulses. We found that both nanoparticles and nanosheets composed of molybdenum oxide were formed. The colloid suspension optical absorbance changes with time, as the colloid ages it changes color; a blue shift is observed within a few days of aging. It results in a band gap increase from 2.55 eV up to 2.9 eV for nearly a month of aging, which we computed through the Tauc method. Raman characterization of the nanostructures shows that the synthesized material turns into a hydrated molybdenum oxide (MoO 3 · n H 2 O). This is consistent with the band gap evolution, which for early aging corresponds to MoO 3 to later achieve the band gap value of a hydrated molybdenum oxide. The nanostructures were also characterized by transmission electron microscopy (TEM) showing that the nanoparticles have a core-shell structure with a raspberry-like shell for medium and small nanoparticles and a smooth homogeneous shell for large nanoparticles. The size distribution peaks at 30–40 nm, with the smallest nanoparticles at 10 nm and the largest at 120 nm. The nanosheets are decorated by tiny nanoparticles. High resolution transmission electron microscopy (HRTEM) images allowed measuring the interplanar distances at the nanosheets, we found the nanosheets are composed by the orthorhombic stable-phase α -MoO 3. SAED measurements confirmed the formation of this molybdenum oxide phase. An absorption band at 830 nm that develops in the few first days of aging of the colloid is of interest for photothermal therapy, which gives the reported nanostructures a good potential for biomedical applications. • Femtosecond laser ablation of solids in liquids for nanomaterials rapid synthesis. • Simultaneous nanoparticle and nanosheet molybdenum oxide laser synthesis. • Band gap modification after molybdenum oxide nanomaterials synthesis due to aging. • Transient plasmonic absorption band of the molybdenum oxide nanomaterials in the near infrared. [ABSTRACT FROM AUTHOR]

Recycling palm oil fuel ash (POFA) into lucrative holey graphene nanosheets will not only save resources but will also prove to be a great solution to avoid the hazards of environmental pollution. The present research aims on studying the effects of temperature and ratio of potassium hydroxide (KOH) during the chemical activation reaction of POFA, resulting in porous graphene sheets with great scope in a variety of industrial applications. These two parameters were studied because of their major influence on the yield, surface area, porosity, and quality of the produced graphene sheets. Porous graphene sheets were prepared by optimizing different activation temperatures (700 °C, 800 °C, and 900 °C) and POFA to KOH impregnation ratios (1:2, 1:3, 1:4, and 1:5). The optimal conditions for producing the best POFA-derived holey graphene in terms of the number of layers, surface area, and porosity were found with impregnation ratio of 1:3 and at temperature of 800 °C. From scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HR-TEM) analyses, it was found that the resulting few layer nanosheets have more uniform porosity at these optimized conditions. We found Brunauer-Emmett-Teller (BET) surface area, pore volume and carbon percentage of 1506.64 m2/g, 0.88 cm3/g and 99% respectively which are comparable to the previous findings using other biomass sources. It was also found that a higher temperature and higher KOH ratio resulted into pore widening and increasing the surface area, but at temperatures beyond the optimized conditions, the surface area and pore volume were reduced due to more vigorous reactions, and volatilization, which led to pore destruction. The present work emphasizes that these parameters have major impact on POFA activation, and their optimisation resulted into good quality graphene nanosheets in a greener and sustainable way, which can be used for many applications including inexpensive energy-storage and water purification applications. [Display omitted] • Graphenic carbon nanosheets obtained from palm oil fuel ash via a simple method. • High surface area, high yield and clean edges obtained at optimized conditions. • Temperature of 800 °C and POFA/KOH ratio of 1:3 gives best product. • Much higher temperature and KOH ratio leads to aggressive reaction giving no product. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO 2), neodymium (Nd3+) doped TiO 2 with the doping levels of 0.3% and 0.5% were synthesised by hydrothermal method and were characterized by powder X-ray diffraction (XRD), UV–vis diffused reflectance spectroscopy (DRS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Ultraviolet X-ray photoelectron spectroscopy (UPS) and high resolution transmission electron microscopy (HRTEM). Doping of Nd3+ ions have been created new surface energy states below the conduction band of TiO 2 which mediate the photoinjected electrons through TiO 2 network to external load without any impediment. The Fermilevel (E f) of TiO 2 was shifted to downward direction upon Nd3+ ion doping confirmed from UPS analysis. An enhanced photoconversion efficiency (PCE) of 10.7% was achieved for the device fabricated using 0.3% Nd3+ ion doped TiO 2 which is higher than that of the device with undoped TiO 2 (10.1%). The noticeable increment in the PCE was due to the reduced charge recombination, longer electron lifetime and improved charge injection form LUMO of the N719 dye to the CB of TiO 2. [Display omitted] • Doping of Nd3+ in TiO 2 created new surface states that mediate the photoinjected electrons without any impediment. • The Fermilevel (E f) of TiO 2 was shifted to a downward direction upon Nd3+ ion doping confirmed from UPS analysis. • Enhanced photoconversion efficiency of 10.7% was achieved for the device fabricated using 0.3% Nd3+ ion-doped TiO 2. [ABSTRACT FROM AUTHOR]

An aquatic plant, water hyacinth was used after modification with poly-aniline (PANI@WH) as an adsorbent for removal of Cr (VI) from aqueous solution. The effect of pH, time, dose and concentration on Cr (VI) removal was investigated following batch adsorption process. The adsorption of Cr (VI) on PANI@WH adsorbent followed Freundlich adsorption isotherm as well as pseudo-second-order kinetic model. Maximum adsorption capacity obtained by isotherm has been achieved as 31.45 mgg−1 at 323K. Adsorption of Cr (VI) proceeds through film diffusion rather than intra-particle diffusion. Thermodynamic studies suggested endothermic and spontaneous nature of adsorption due to positive enthalpy and negative Gibbs free energy values. On the basis of the value of mean free energy, Gibb's free energy of adsorption and activation energy obtained in the present investigation suggested that adsorption of Cr (VI) on polyaniline coated water hyacinth occurs through physical adsorption. Surface characterization studies such as Field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared, Brunauer, Emmett and Teller surface area, X-ray photoelectron spectroscopy, X-ray diffractometer, atomic force microscopy and high resolution transmission electron microscopy illustrated adsorption mechanism of the adsorbent. The predicted % removal of Cr (VI) was obtain by response surface methodology model are compared with the experimental % removal of Cr (VI) obtained by batch adsorption process. Prepared composite adsorbent can be reused for several cycles and it gives 85% Cr (VI) removal efficiency even after 4th cycle which shows its good regeneration ability. [Display omitted] • PANI@WH is low cost adsorbent and offered 98.5% Cr (VI) removal. • Freundlich isotherm is followed by Cr(VI) adsorption on PANI@WH. • Cr (VI) adsorption on Cr(VI) on PANI@WH followed physical adsorption. • The adsorption of Cr(VI) on PANI@WH followed pseudo-second-order kinetic model. • FESEM,EDX, and XPS studies confirmed the adsorption of Cr(VI) on PANI@WH. [ABSTRACT FROM AUTHOR]

The present study reports substantial coating of biocompatible polymer Carboxymethyl Cellulose (CMC) on magnetic nanoparticles (MNPs) of Lanthanum Strontium Manganese Oxide (LSMO) also called manganite, as a novel attempt, for magnetic Hyperthermia applications. Two series of manganite (La 1-x Sr x MnO 3) were synthesized through Citrate-gel technique choosing "x" as (0.3) and (0.33). X-ray diffraction (XRD) study has shown satisfactory phase formation of MNPs in accordance with the standard patterns. High resolution transmission electron microscopy (HRTEM) was done to evaluate the effect of CMC on particles' morphology after coating. The Fourier transform infrared spectroscopy (FTIR) has displayed successful attachment of CMC on the surface of MNPs and adsorbed coating amounts have been assessed through Thermogravimetric analysis and Differential Scanning Calorimetry (TGA/DSC). The coated LSMO were dispersed in Phosphate Buffer Saline (PBS, pH = 7) as an innovative try, to see the potential of these mediators towards effective Hyperthermia applications in fluid form at a suitable frequency of the applied magnetic field. The CMC coated MNPs have achieved quite appreciable specific absorption rate (SAR) up to 225 W/g and intrinsic loss power (ILP); showing a positive sign for their possible usage in Hyperthermia therapy. [Display omitted] • Biocompatible CMC coating on La 1-x Sr x MnO 3 (x = 0.3 & 0.33). • CMC found to be suitable for encapsulating MNPs. • Appreciable magnetization by CMC coated MNPs. • Efficient heating of CMC coated NPs for Hyperthermia applications. • Significant SAR (225.4 W/g) when dispersed in PBS. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDCs) have attracted immense interest of the scientistific community due to their unique physico-chemical characteristics and applications in optoelectronic devices. Interface between TMDCs and the substrate plays a leading role in the performance and reliability of the devices. Swift heavy ion (SHI) irradiation is used as a most valuable tool for altering material's physical, chemical, structural, surface and interface properties in a controlled manner. In this work, characteristics of SHI irradiation caused defects in MoSe 2 sheets on different substrates were presented to study the role of the substrate on defect engineering of MoSe 2. Morphologies of the SHI induced latent tracks on MoSe 2 were detected by atomic force microscopy (AFM), which suggest that substrate plays a dominate role on determining the shape of the latent tracks on 2D TMDCs. Cross-section morphology of SHI irradiated MoSe 2 on different substrates was examined by high resolution transmission electron microscopy (TEM). The lattice mismatch between MoSe 2 sheets and the substrate leads to different depths of the atomic mixing at their interface. Dependence of vibrational modes of MoSe 2 nanosheets on the substrates was studied by Raman spectroscopy and a counterbalance effect among the electron doping, charge localization and decoupling effect is expected to determining the shift of A 1g mode in SHI irradiated MoSe 2 sheets. Electrical properties degradation of the MoSe 2 field effect transistor (FET) confirms the SHI irradiation that cause charge localization. This study provides fundamental insights in understanding the influence of the substrate on defect engineering in TMDC materials and a practical guide on choosing the conditions to obtain certain parameters of irradiated TMDC materials. • Shape of latent tracks on MoSe 2 with a small thickness depends on the substrate. • Interface profile depends on the lattice mismatch between MoSe 2 and substrates. • Dependence of vibrational modes of MoSe 2 on the substrates is studied in detail. • Electrical property degradation confirms irradiation caused charge localization. [ABSTRACT FROM AUTHOR]

This study features structural and photometric aspects of a down-converted green emanating erbium (Er3+) activated nanophosphor synthesized via a versatile and environmentally benign urea aided solution combustion procedure. The powder X-ray diffraction pattern (PXRD) of optimal sample SrGd 1.96 Er 0.04 Al 2 O 7 studied qualitatively by employing the Rietveld refinement practice, disclosed the tetragonal crystal phase with space group 14/mmm (139), consisting grains of size 50.03 nm. Surface morphology and grain size of nanopowders were well investigated by electron microscopy practices like scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). SEM micrograph gave clear insight that Er3+ doped nanophosphors possess slightly agglomerated particles with pores, voids and cracks due to high pressure breakout of gases while combustion synthesis. TEM and SEM images revealed the size of nanoparticles in the ambit of 40–60 nm which was in coherence with that obtained from the scherrer's equation, while the inter-fringes distance corresponding to diffraction plane (116) was calculated to be 0.27 nm from the HRTEM image. The desired nanophosphor showed brilliant green emission with an intense peak at 551 nm attributed to 4S 3/2 → 4I 15/2 transition of Er3+ ions, as analyzed through photoluminescent (PL) emission spectra monitored via near ultraviolet excitation wavelength (381 nm) with an optimal doping concentration of 2.0 mol%. Advanced photometric features like CIE color coordinates (0.3017, 0.6043), CCT (6032K), and color purity (76.52%) confirmed their green glow and are found to be in harmony with standard green emission. The study offers a luminous cool green emanating component for the fabrication of WLEDs and advanced optoelectronic appliances. [Display omitted] • SrGd 2 Al 2 O 7 :Er3+ nanophosphors were prepared via combustion procedure. • Absolute crystal phase was analyzed using XRD assisted Rietveld Refinement technique. • The new down-converted nanophosphors exhibit excellent green luminescence. • CIE chromaticity co-ordinates, CCT and color purity were inspected thoroughly. • Potential candidate for cool WLEDs, lasers and optical sensors. [ABSTRACT FROM AUTHOR]

The current work focuses on accessing the potential aptitude of the rare-earth-doped Gadolinium oxide (Gd 2 O 3) nanoparticles as a function of dopant concentrations with biological entities in aqueous media. A series of Pr@Gd 2 O 3 NPs were synthesized by fast and economically viable microwave-assisted methodology. Various high end techniques such as high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), vibrating sample magnetometric studies, thermal gravimetric analysis and scanning electron microscopy (SEM), were employed to characterize the prepared particles. The optical, magnetic and thermal properties of Pr-doped Gd 2 O 3 (doping percentage = 5, 10 and 15%) were scrutinized in relationship with their optical band gap, spectroscopic properties, defect states and thermal stability. In order to access the effect of different concentrations of dopant on the biocompatibility of Gd 2 O 3 , in vitro biocompatibility studies on the bacterial and fungal stains have been performed. These variables were on the basis of dopant amount (5, 10 and 15% of Pr) and initial concentration (10, 50, 100 ppm). The outcomes of in-vitro blood compatibility assay showed the biocompatible aptitude of effect of Pr@Gd 2 O 3 NPs as a function of initial concentration ranging from 10, 50, 100 ppm. The relative effect on the chromosomal aberrations in root meristems of A. cepa shown the reduction of 20%, 23%, 8% in mitotic index (MI), correlative mitotic index (CMI) and index of phase (PI) values with increase in Pr doping amount. The high biocompatibility was observed for 10 ppm of Pr@Gd 2 O 3 NPs. Collectively; the outcomes of the present study exemplify the various properties of Pr@Gd 2 O 3 NPs with potential biomedical efficacies. [Display omitted] • Synthesis of Pr@Gd 2 O 3 NPs through a fast, simple, facile and ecologically friendly microwave assisted technique. • Plausible effect of doping on optical, magnetic and thermal properties of Pr@Gd 2 O 3 NPs. • Evaluating alternations in toxicological effects with doping. [ABSTRACT FROM AUTHOR]

Mixed phase molybdenum oxide (mp-MoO 3) nanocomposite (NC) along with hexagonal (h-MoO 3) and orthorhombic (o-MoO 3) nanoparticles (NPs) were synthesized via easy and cost-effective internal combustion method using water/ethanol mixture, water, and methanol solvents. The formation mechanisms of h-MoO 3 , o-MoO 3 , and mp-MoO 3 have been investigated using different physical methods such as XRD (X-ray diffraction), FTIR (fourier transform infrared spectroscopy), FESEM (field emission scanning electron microscopy), HRTEM (high resolution transmission electron microscopy, and SAED (selected area electron diffraction). The potential of prepared NPs and NC on the adsorptive removal of methylene blue (MB) was investigated through the adsorption batch process with variation in the adsorbent dosage, pH, and temperature of the solution. The confirmation of dye adsorption over adsorbent surfaces has been elucidated by employing FTIR and FESEM after the adsorption process. The influence of different NPs and NC on the adsorption efficiency indicates the possibility of physical, chemical as well as electrostatic interaction between adsorbent-adsorbate interface. Thermodynamical parameters were calculated and analyzed for the validity of the adsorption phenomenon. Various kinetic study models such as pseudo-first-order (PFO), pseudo-second-order (PSO), and Intra-particle diffusion (IPD) were fitted to the experimental data to explore the rate-controlling step and for understanding the adsorption mechanism. The mp-MoO 3 NC was observed to have the best adsorption efficiency as well as a better adsorption rate. Therefore synthesized mp-MoO 3 NC showed great potential for dye adsorption and would be seen as the futuristic adsorbent materials for sustainable water treatment technology. • Mixed phase molybdenum oxide (mp-MoO 3) has been synthesized using internal combustion method using urea as a fuel. • The mp-MoO 3 possesses higher methylene blue adsorption efficiency as compared to hexagonal (h-MoO 3) and orthorhombic (o-MoO 3). • The adsorption efficiency was attributed to the improved surface charge, surface area and increased porosity in the material. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) based heterostructures were prepared by oxygen plasma treatment and atomic layer deposition (ALD) of TiO 2 carried on MWCNTs. Different TiO 2 structures (island, granular and continuous forms) on the nanotubes were obtained by varying the processing parameters. Chemical inertness of MWCNTs led to the ALD of TiO 2 in an island form. Oxygen plasma treatment ensured deposition of a continuous TiO 2 film, 5 nm in thickness. A granular form of TiO 2 was obtained on oxygen plasma treated MWCNTs using shorter duration of Ti-precursor pulse. Different imaging modes in high resolution transmission electron microscopy visualized TiO 2 nanostructures and defects in MWCNT walls. The latter were also confirmed by Raman spectroscopy. The morphology of TiO 2 and oxygen plasma treatment of the MWCNTs highly affected the NO 2 sensing behavior of chemiresistive heterostructure sensors at room and elevated temperatures. All investigated sensors exhibited a decrease in the resistance upon exposure to NO 2 gas which implies a p-type sensor response. The granular TiO 2 /MWCNTs heterostructure showed the highest response towards NO 2 gas as compared to the island and continuous forms. [Display omitted] • Manipulating the duration of the Ti-precursor pulse in ALD influence the TiO2 morphology on MWCNTs. • Nanoscopic characterization of MWCNT/TiO2 heterostructures by HR-TEM, HAADF, STEM-EDX. • Oxygen plasma treatment and TiO2 morphology affect the NO2 sensing behavior. • Engineered TiO2 in granular form on oxygen plasma treated MWCNTs exhibits highest response towards NO2. [ABSTRACT FROM AUTHOR]

Superparamagnetic iron oxide nanoparticles (MNPs) have the potential to act as heat sources in magnetic hyperthermia. The key parameter for this application is the specific absorption rate (SAR), which must be as large as possible in order to optimize the hyperthermia treatment. We applied a Plackett-Burman fractional factorial design to investigate the effect of total iron concentration, ammonia concentration, reaction temperature, sonication time and percentage of ethanol in the aqueous media on the properties of iron oxide MNPs. Characterization techniques included total iron content, Fourier Transform Infrared Spectroscopy, X-Ray Diffraction, High Resolution Transmission Electron Microscopy, and Dynamic Magnetization. The reaction pathway in the coprecipitation reaction depended on the initial Fe concentration. Samples synthesized from 0.220 mol L−1 Fe yielded magnetite and metastable precipitates of iron oxyhydroxides. An initial solution made up of 0.110 mol L−1 total Fe and either 0.90 or 1.20 mol L−1 NH 3(aq) led to the formation of magnetite nanoparticles. Sonication of the reaction media promoted a phase transformation of metastable oxyhydroxides to crystalline magnetite, the development of crystallinity, and the increase of specific absorption rate under dynamic magnetization. [Display omitted] • The coprecipitation pathway depended on the initial concentration of Fe. • SAR was highest for samples obtained from 0.110 mol L−1 Fe, in 0.90 mol L−1 NH 3(aq) , sonicated for 1 h. • Sonication of the reaction mixture boosted phase transformation to magnetite. • Fractional factorial designs are a powerful tool for steering the synthesis of Fe 3 O 4 MNPs. [ABSTRACT FROM AUTHOR]

The clean and low-cost preparation of advanced materials for green energy storage applications is a critical step towards sustainable development. Here, the rapid modification of CoO in molten salt is proposed as a low-cost approach for the scalable preparation of Co-based oxides with enhanced Li-storage performance. The phase evolution of CoO upon molten salt treatment is investigated by X-ray diffraction (XRD), electron microscopy, N 2 adsorption–desorption and Raman spectroscopy. The molten salt treatment of CoO under dry and humid Ar atmosphere leads to the formation of dual-phase structured CoO/Co 3 O 4 and Li 0.065 Co 0.935 O, respectively. High resolution transmission electron microscopy and fast Fourier transform analysis of samples after Li insertion and extraction process confirm the formation of nanostructured Co-Li 2 O. The Co phase formed from CoO/Co 3 O 4 and Li 0.065 Co 0.935 O is found to have hexagonal close packed (hcp) and face central cubic (fcc) structure, respectively. The Li-storage performances of these materials are correlated to their structural/microstructural characteristics. This article presents a simple, scalable and environmentally-friendly approach for modification of Co-oxide materials for lithium ion battery anode applications. • Potentially sustainable modification of CoO in high-temperature molten salts. • Molten sat formation of Li 0.065 Co 0.935 O in humid atmosphere and mechanisms. • Preparation of dual-phase structured CoO/Co 3 O 4 in dry atmosphere and mechanisms. • Correlation between structural/morphological features and Li-storage performance. • Formation of nanostructured hybrid Co-Li 2 O with cubic- or hexagonal-Co. [ABSTRACT FROM AUTHOR]