Nm In Average Size Research Articles

Vanadium-doped TiO<sub>2</sub> Adsorbent-Photocatalyst for Organic Dye Treatment

This study focuses on the synthesis of V-doped TiO2 materials using a modified polyol method to enhance their efficiency. The obtained materials were characterized by various methods such as XRD, EDX, FTIR, SEM, TEM-SAED, Raman, and UV-Vis DRS. The results indicated the crystalline anatase phase of TiO2, with spherical morphology and an average size of 30nm. The UV-DRS measurement demonstrated that doped materials have a lower bandgap than the pristine TiO2. The material possesses dual functionality, with adsorption capability and photocatalytic activity applied to treat organic dye contaminants. Evaluation of MB degradation under UV irradiation revealed an exceptional efficiency of up to 99% within a remarkably short duration of 30 minutes. Furthermore, the catalyst exhibited robust recovery efficiency exceeding 99% after 2 regeneration cycles and retention of approximately 80% after four cycles.

Sonicated polyethylene terephthalate nano- and micro-plastic-induced inflammation, oxidative stress, and autophagy in vitro

The environmental presence of nano- and micro-plastic particles (NMPs) is suspected to have a negative impact on human health. Environmental NMPs are difficult to sample and use in life science research, while commercially available plastic particles are too morphologically uniform. Additionally, this NMPs exposure exhibited biological effects, including cell internalization, oxidative stress, inflammation, cellular adaptation, and genotoxicity. Therefore, developing new methods for producing heterogenous NMPs as observed in the environment is important as reference materials for research. Thus, we aimed to generate and characterize NMPs suspensions using a modified ultrasonic protocol and to investigate their biological effects after exposure to different human cell lines. To this end, we produced polyethylene terephthalate (PET) NMPs suspensions and characterized the particles by dynamic light scattering and scanning electron microscopy. Ultrasound treatment induced polymer degradation into smaller and heterogeneous PET NMPs shape fragments with similar surface chemistry before and after treatment. A polydisperse suspension of PET NMPs with 781 nm in average size and negative surface charge was generated. Then, the PET NMPs were cultured with two human cell lines, A549 (lung) and HaCaT (skin), addressing inhalation and topical exposure routes. Both cell lines interacted with and have taken up PET NMPs as quantified via cellular granularity assay. A549 but not HaCaT cell metabolism, viability, and cell death were affected by PET NMPs. In HaCaT keratinocytes, large PET NMPs provoked genotoxic effects. In both cell lines, PET NMPs exposure affected oxidative stress, cytokine release, and cell morphology, independently of concentration, which we could relate mechanistically to Nrf2 and autophagy activation. Collectively, we present a new PET NMP generation model suitable for studying the environmental and biological consequences of exposure to this polymer.

Delayed surface degradation in W-Ta alloys at 400 °C under high-fluence 40 eV He plasma exposure

The surface modifications in W-xTa alloys (x = 0, 6, 11 wt.%), as potential material candidates for tokamak components facing the fusion plasma, have been assessed at a temperature of ∼400 °C, by exposing the material surface to 40 eV He for increasing He fluences up to 1027 m−2 and flux of ∼1023 m−2 s−1. Surface wave-like structures appear in all samples at a fluence of ∼1026 m−2, whereas at the higher fluence of ∼1027 m−2 the material's surface is characterised by the presence of blisters and ablations. This suggests a new critical fluence for blistering in pure He plasma to be between 1026 and 1027 m−2. There is also a near-surface layer with a thickness of ∼200 nm that contains He bubbles of 2.20–2.70 nm in average size. Increasing Ta content leads to a small reduction in bubble size, and to clear reductions in the presence of blisters and ablations. Ta alloying can improve the hardness and yield strength and reduce the He diffusivity in the material. This therefore delays bubble formation and surface blistering and ablations that are affected by these mechanical properties. This was exemplified at the highest fluence by a large mitigation of surface material ablation.

Remarkable low-temperature hydrogen cycling kinetics of Mg enabled by VH nanoparticles

Nanoscaled catalysts have attracted much more attention due to their more abundant active sites and better dispersion than their bulky counterparts. In this work, VHx nanoparticles smaller than 10 nm in average size are successfully synthesized by a simple solid-state ball milling coupled with THF washing process, which are proved to be highly effective in enhancing the hydrogen absorption/desorption kinetics of MgH2 at moderate temperatures. The nano-VHx-modified MgH2 releases hydrogen from 182 °C, which is 88 °C lower than additive-free MgH2. The release of hydrogen amounts to 6.3 wt.% H within 10 min at 230 °C and 5.6 wt.% H after 30 min at 215 °C with initial vacuum. More importantly, the dehydrogenated MgH2+10 wt.% nano-VHx rapidly absorbs 5.2 wt.% H within 3 min at 50 °C under 50 bar H2. It even takes up 4.3 wt.% H within 30 min at room temperature (25 °C) under 10 bar H2, exhibiting superior hydrogenation kinetics to most of the previous reports. Mechanistic analyses disclose the reversible transformation between V and V-H species during the hydrogen desorption-absorption process. The homogeneously distributed V-based species is believed to act as hydrogen pump and nucleation sites for MgH2 and Mg, respectively, thus triggering fast hydrogenation/dehydrogenation kinetics.

Zn and Co ferrite nanoparticles: towards the applications of sensing and adsorption studies.

An important deliberation of this current work is the impending applications of bivalent transition metals doped with nano ferrites and to study their emerging properties of magnetically active ferrites, which constitute oxides of iron (different conformers most demanding γ-Fe2O3) and transition metal complexes of bivalent metal oxides like cobalt (Co(II)) and magnesium (Mg(II)). Fe3+ ions occupy tetrahedral sites; the rest of Fe3+ and the Co2+ ions occupy octahedral sites. For the synthesis, a self-propagating method of combustion at lower temperature was used. Zinc and cobalt nano ferrites are synthesized from the chemical coprecipitation method of 20 to 90 nm in average size, characterized thoroughly employing FTIR and PXRD and surface morphology studied using SEM. These results explain the existence of ferrite nanoparticles in cubic spinel. Magnetically active metal oxide nanoparticles are now commonly employed in main studies of sensing, absorption, and other properties. All studies showed the interesting results.

Calcination-dependent microstructural and optical characteristics of eco-friendly synthesized ZnO nanoparticles and their implementation in analog memristor application

Using Camellia Sinensis leaf aqueous extract as a friendly reducing, capping, and stabilizing agent, ZnO nanoparticles (NPs) are synthesized via the green process. The plausible mechanism for the ZnO NPs formation is proposed as the chelation of Zn, or metal complexation, under the thermally assisted energy from the annealing process. An inclusive study on the effect of the annealing process on the ZnO NPs is conducted from room temperature to 850 °C. The structural, morphological, thermal, and optical characteristics and their intercorrelation with annealing temperature are thoroughly studied. In particular, the change of crystalline texture coefficient contributed to the systematic perspective of the shape changes of the ZnO NPs. The (002)-oriented growth becomes preferred at 400–700 °C, corresponding to the increase of conical-shaped NPs from 150 to 250 nm in average size. With further temperature, the preferred growth transfers from (002) to (100) orientations, and polygonal spherical-shaped NPs can be obtained. Photoluminescence spectra reveal that singly and doubly ionized oxygen vacancies are the most dominant in the NPs. With the optimized green materials, implementing an eco-friendly memristor based on ZnO NPs found promising for electronic devices.

Aerosol Spray Drying Guided Synthesis of Ultrasmall Alloyed Bimetallic Nanoparticles Supported on Silica for Catalytic Semihydrogenation.

Supported bimetallic nanoparticles (NPs) with ultrasmall sizes and homogeneous alloying are attractive for catalysis. However, facile synthesis of this type of material remains very challenging. Here, the aerosol drying impregnation method for rapid, scalable, and general synthesis of silica-supported bimetallic NPs is proposed. The method relies on aerosol spray drying to promote the mixing and dispersing of binary metal precursors on SiO2 . It is capable of controlling the composition and size of bimetallic NPs and avoids the use of expensive metal complex salts and complicated experiment procedures. Twelve permutations combining a noble metal (Pd, Ru, and Pt) and a base one (Fe, Co, Ni, and Cu) with ultrasmall sizes (1.4-2.2nm in average size), uniform dispersion, and good alloying are synthesized. Interesting activity and selectivity trends in catalytic semihydrogenation of phenylacetylene over the supported Pd-based NPs can be observed. The silica-supported PdNi NPs deliver both high activity and styrene selectivity. Spectroscopic and density functional theory calculation results reveal the improved chemoselectivity originated from the suitably down-shifted d-band center of the PdNi NPs inducing an increased energy barrier for overhydrogenation and a weakened styrene adsorption.

A New Platform of Iron Oxide-Based Nanoparticles Assay Using GMR Chip-Based Sensor With Microcontroller

The low-cost, simple, and fast quantitative assay of magnetic nanoparticles (MNPs) is important for the development of magnetic-based immunoassay applications. However, the bulky sensing element and instruments of the recent iron oxide-based MNPs assays are still concerns that should be resolved. This article reports the new platform of an iron oxide-based MNPs label assay using the commercial giant magnetoresistance (GMR) chip AAL024, manufactured by Nonvolatile Electronics (NVE) Corporation, complemented with a basic differential amplifier circuit and Arduino microcontroller (AM) to acquire the digital output voltage. The as-prepared Fe3O4@Ag label possessed (15 ± 2.6) nm of average size and behaved as soft ferromagnetic with 52.1 emu/g of saturation magnetization, and 0.15 kOe of coercive field. Sensor performance for magnetic field detection, as well as Fe3O4@Ag nanoparticles label assay, was evaluated. The results show the implementation of a basic differential amplifier op-amp circuit succeed to magnify the sensor’s response to the magnetic field up to 23 times with the output voltage in the order of volt. The employment of the AM as a voltage supply of the GMR chip, an analog-to-digital converter, and a voltage gauge simplifies the data acquisition without the additional measuring instrument. Meanwhile, for the purpose of the Fe3O4@Ag nanoparticles label assay, the sensor revealed promising performance due to the high signal linearity and the rapid detection which is only 30 s with acceptable signal stabilities.

Oral colon-targeted mucoadhesive micelles with enzyme-responsive controlled release of curcumin for ulcerative colitis therapy

Although multitudinous nanoscale drug-delivery systems (DDSs) have been recommended to improve anti-ulcerative colitis (UC) outcomes, to enhance the mucoadhesion of nanosystems on the colon and specifically release the loaded drugs in response to the colon micro-environment would be critical factors. The application of curcumin (Cur), an acknowledged anti-UC phytochemical compound, for UC therapy requires more efficient nano-carriers to improve its therapeutic outcome. Herein, we developed the colon-targeted nano-micelles with mucoadhesive effect and Azo reductase-triggered drug release profiles for Cur delivery in UC treatment. Specifically, the amphiphilic block polymer containing the Azo-reductase sensitive linkage (PEG-Azo-PLGA), and catechol-modified TPGS (Cat-TPGS) were synthesized respectively. Based on the self-assembly of the mixed polymers, Cur-micelles (142.7 ± 1.7 nm of average size, 72.36% ± 1.54% of DEE) were obtained. Interestingly, the Cur-micelles exhibited the Azo-reductase sensitive particle dissociation and drug release, the enhanced cellular uptake and the prolonged retention on colonic mucosa, mediated by the strong mucoadhesion of catechol structure. Ultimately, Cur-micelles significantly mitigated colitis symptoms and accelerated colitis repair in DSS-treated mice by regulating the intestinal flora and the levels of pro-inflammatory factors (MPO, IL-6, IL-1β, and TNF-α) related to TLR4/MyD88/NF-κB signaling pathway. This work provides an effective drug delivery strategy for anti-UC drugs by oral administration.

Solar Photocatalysis of TiO<sub>2</sub> Supported Natural Palygorskite Nanofibers Elaborated by a One_Pot Mechanochemical Route

This study reports the successful synthesis of supported TiO2_Palygorskite nanocomposites by a one-pot dry mechanochemical route. Indeed, the elaboration procedure involved an in-situ reaction between accessories carbonates present in raw fibrous palygorskite clay and titanyl sulfate (TiOSO4) precursor under variable grinding conditions, essentially ball/solid matter mass ratio and rotation velocity. This yielded after air annealing at 600%C for 1 h to the immobilization of anatase TiO2 nanoparticles (≈8 nm of average size) as evidenced by XRD and TEM analyses. Once the conditions of elaboration were optimized, the photocatalytic properties were evaluated under 3 conditions: artificial UV radiation, artificial solar radiation (UV + visible range) and under dynamic solar illumination taking into account the discontinuities of the solar resource. The results allowed the estimation and comparison of the catalyst’s capabilities and showed its ability to work under natural irradiation. The so developed supported photocatalysts TiO2/Palygorskite exhibited a good activity towards the removal of Orange G (OG) dye from aqueous media under artificial UV and natural solar radiations.

In situ crystallization of 0D perovskite derivative Cs3Bi2I9 thin films via ultrasonic spray

Cs3Bi2I9 has been proposed to be an alternate candidate for various optoelectronic applications to meet the stability and toxicity issues associated with the highly performing organic lead halide perovskites. In the present work, we report the in situ formation of cesium bismuth iodide thin films by ultrasonically assisted sequential spray deposition of BiI3 and CsI in ethanol-based precursor solutions. The films formed by varying the layer configurations and relative molarity were investigated to identify the optimum conditions to obtain pure Cs3Bi2I9 films. Further, we probe their structure, morphology, optical and electronic properties in combination with computational studies. X-ray diffraction and Raman spectroscopy confirmed the crystallinity and chemical structure of the spray cast perovskite films. Scanning electron microscopy images present the surface morphology composed of uniformly distributed hexagonal grains of ∼ 280 nm in average size. The absorption coefficient of the films was evaluated in the order of ~ 106 cm−1 using UV–Vis–NIR spectral analysis. The calculated direct band gap value of 1.99 eV was in accordance with the theoretical calculations. Furthermore, the optimized Cs3Bi2I9 film was photoconductive. The I-V characteristics of FTO/ZnO/Cs3Bi2I9/C-Ag heterojunction revealed a significant rectification behavior with a diode factor of 1.75. FTO/CdS/Cs3Bi2I9/C-Ag heterojunction showed a Voc of 300 mV and Jsc of 0.003 mA cm−2. Our results imply that the spray deposited Cs3Bi2I9 films have a profound potential for applications in photodetectors and solar cells upon detailed investigations.

All-optical encryption by a heterodyne Kerr gate in multilayer reduced graphene oxide decorated with Pt nanoparticles

Herein is reported how the inhibition of the imaginary part of the electrical impedance exhibited by reduced graphene oxide (rGO) yields to stronger conductivity together to an enhancement in its optical nonlinearities. A highly uniform incorporation of plasmonic nanoparticles in the samples was identified to be responsible for the observed effects, while protoplasmatic nanoparticles or random decoration did not promote any important change in the studied parameters. Platinum particles featuring approximately 3 nm in average size were homogeneously decorated on the surfaces of rGO following a two-steps growth procedure. The vectorial nature in the third-order nonlinear optical response exhibited by rGO decorated with platinum nanoparticles (Pt/rGO) was analyzed by a two-wave mixing experiment. Interferometric irradiance and polarization patterns seem to generate different physical mechanisms responsible for the nonlinear refractive index exhibited by the nanostructures. An ablation threshold of 0.35 J/cm 2 was measured. The contrast in the superposition of two-input binary polarized optical signals was employed to propose an exclusive disjunctive logic gate based on a heterodyne optical Kerr gate. The polarization-selectable multi-photonic properties were explored by nanosecond pulses at 532 nm wavelength and a straightforward XOR encryption function was designed. The optical Kerr effect exhibited by Pt/rGO can be contemplated for developing all-optical switching devices. Immediate applications for encrypting and processing ultrafast functions can be also considered. • Excellent dispersion of Pt nanoparticles in reduced graphene oxide is reported. • Inhibition of the imaginary part in the electrical impedance was obtained. • An enhancement in optical nonlinearities in Pt decorated rGO is presented. • Kerr signals for controlling all-optical encryption were analyzed.

Green Synthesized Silver Nanoparticles Immobilized on Activated Carbon Nanoparticles: Antibacterial Activity Enhancement Study and Its Application on Textiles Fabrics.

This research aimed to enhance the antibacterial activity of silver nanoparticles (AgNPs) synthesized from silver nitrate (AgNO3) using aloe vera extract. It was performed by means of incorporating AgNPs on an activated carbon nanoparticle (ACNPs) under ultrasonic agitation (40 kHz, 2 × 50 watt) for 30 min in an aqueous colloidal medium. The successful AgNPs synthesis was clarified with both Ultraviolet-Visible (UV-Vis) and Fourier Transform Infrared (FTIR) spectrophotometers. The successful AgNPs–ACNPs incorporation and its particle size analysis was performed using Transmission Electron Microscope (TEM). The brown color suspension generation and UV-Vis’s spectra maximum wavelength at around 480 nm confirmed the existence of AgNPs. The particle sizes of the produced AgNPs were about 5 to 10 nm in the majority number, which collectively surrounded the aloe vera extract secondary metabolites formed core-shell like nanostructure of 8.20 ± 2.05 nm in average size, while ACNPs themselves were about 20.10 ± 1.52 nm in average size formed particles cluster, and 48.00 ± 8.37 nm in average size as stacking of other particles. The antibacterial activity of the synthesized AgNPs and AgNPs-immobilized ACNPs was 57.58% and 63.64%, respectively (for E. coli); 61.25%, and 93.49%, respectively (for S. aureus). In addition, when the AgNPs-immobilized ACNPs material was coated on the cotton and polyester fabrics, the antibacterial activity of the materials changed, becoming 19.23% (cotton; E. coli), 31.73% (polyester; E. coli), 13.36% (cotton; S. aureus), 21.15% (polyester; S. aureus).

Biosynthesis of gold nanoparticles for the treatment of osteoarthritis alone or in combination with Diacerein® in a rat model.

Gold (Au) compounds were used as an effective therapeutic agent for various inflammatory diseases; however, the use of Au compounds becomes limited because of its association with several side effects. Hence, gold nanoparticles (AuNPs) were developed as a new option for the medical proposes. However, the safety evaluation of gold nanoparticles (AuNPs) in osteoarthritis (OA) treatment remains vague. This study aimed to biosynthesize, characterize and evaluate the therapeutic effects of biosynthesized AuNPs and/or Diacerein® (DIA) in experimental OA. OA was induced by a single injection of monosodium iodoacetate (3mg/joint) in the intra-articular knee of female rats. Normal rats (N-rats) and OA-rats were treated orally for 5weeks as follow: untreated N-rats; untreated OA-rats; N-rats received DIA (50mg/kg b.w); N-rats received AuNPs (30μg/kg b.w.); N-rats received AuNPs plus DIA; OA-rats received DIA; OA-rats received AuNPs, and OA-rats received AuNPs plus DIA. Blood, knee cartilage, liver and kidney samples were collected for biochemical and histological analysis. The synthesized AuNPs were nearly spherical with average size of 20nm and zeta potential of 33mV. AuNPs and DIA induced a significant improvement in serum inflammatory cytokines, biochemical parameters, estrogen level, hepatic and renal oxidative markers, hepatic DNA fragmentation, genomic template stability and cartilage joint histology of OA-rats. AuNPs were more effective than DIA and the combined treatment was more effective than the single treatment. It could be concluded that AuNPs are promising for the treatment of OA alone or in combination with DIA.

Neutron irradiation response of explosion-welded CuCrZr/316LN joints for ITER application

Explosion-welded CuCrZr/316LN joints, which serve as key joining components in enhanced-heat-flux type first wall panels of ITER, have been neutron irradiated in the BR2 reactor (Belgium) at <190 °C, up to 0.3 dpa. The joints have maintained good structural integrity after irradiation and were free of void swelling. Radiation defects featuring black-spot contrasts were produced on both sides of the CuCrZr/316LN interface. They were on the order of 1022 m−3 in number density and all less than 4 nm in average size. Radiation-enhanced diffusion might have favoured the dissolution of interlayers which were characteristic of pristine CuCrZr/316LN joints, and accelerated the diffusion of key elements (e.g. Cu, Fe) across the interface. The joint interface experienced an increase of Vickers hardness by ~ 21% (∆Hv = 48) after neutron irradiation. Heat treatments of 500 °C/1 h resulted in moderate softening of the interface, while 800 °C/1 h gave rise to a complete elimination of irradiation-induced hardening effect, respectively.

Fabrication of mesostructured Y2O3:Eu3+ materials from metal–organic frameworks and their H2O2-sensitive turn-off luminescence

Mesostructured Y2O3:Eu3+ phosphor particles were fabricated by a pyrolytic conversion from a pertinent metal–organic framework (MOF), namely, MOF-76(Y):Eu with 1,3,5-benzenetricarboxylic acid ligands, aiming at luminescence sensing of H2O2. Large rod-like MOF-76(Y):Eu particles 301 ± 150 μm in average length were initially obtained by a reaction at 80 °C for 24 h. They were converted to rod-like Y2O3:Eu3+ particles 122 ± 34 μm in average length after heating at 500 °C. The Y2O3:Eu3+ particles actually consisted of primary nanoparticles 7.55 ± 1.43 nm in average size and had a mesoporous structure with a high specific surface area of 80.8 m2 g−1. The photoluminescence intensity of the Y2O3:Eu3+ particles decreased after treating with an aqueous H2O2 solution, which was recognized as H2O2-responsive turn-off luminescence. Three other kinds of Y2O3:Eu3+ particles, including those obtained from other MOF particles synthesized at room temperature, were also prepared and the effects of the microstructure on the degree of turn-off luminescence were examined. It was then observed that the H2O2-sensitivity was enhanced more effectively by using the MOF-derived Y2O3:Eu3+ particles having the higher specific surface area.

Improvement of antifungal and antibacterial activities of food packages using silver nanoparticles synthesized by iturin A

Contamination of food with food-borne bacteria and fungi presents significant hazards to food preservation and human health. Iturin A has attractive antifungal activity but low antibacterial activity, while silver nanoparticles (AgNPs) have significant antibacterial activities but present a potential hazard to human health. To overcome these limitations, iturin was used to synthesize AgNPs and form iturin-AgNPs, which were mono-dispersed and 20 nm in average size within the range of 10–30 nm. The formation of iturin-AgNPs involved the production of O2•− by the phenolic groups of iurin A under UV irradiation and in the presence of O2. The antimicrobial activities of iturin-AgNPs and the AgNPs (average size 20 nm) stabilized by polyvinyl pyrrolidone (PVP-AgNPs) were evaluated against typical food borne bacteria and fungi in vitro. Iturin-AgNPs was also prepared as paper packages for the use in protection of oranges from fungal contamination alone and the use of prevention of chicken from bacterial contamination with the comparison of PVP-AgNPs. The iturin-AgNPs showed wider antimicrobial spectrum, a lower silver concentration, and higher antibacterial and antifungal activities than PVP-AgNPs. The study developed a new agent to protect foods from bacterial and fungal contamination during storage.

Physical Vapor Deposited [Co:Cd-(dtc)2]/SnO2 Dual Semiconductor Systems: Synthesis, Characterization and Photo-Electrochemistry

Current work reports the fabrication of cadmium, cobalt and cobalt doped cadmium semiconductor chalcogenide [Cd-(dtc)2 [dtc = dithiocarbmate], Co-(dtc)2, and Co:Cd-(dtc)2] complexes using iso-propylammonium dithiocarbamate precursor grown into thin films via physical vapor deposition (PVD) for the first time. Cubic crystals having 18 nm of average size were revealed via X-ray diffraction. Varied molecular arrangements and bonding types were disclosed by Fourier transform infrared spectroscopy. Bandgap tailoring was done by doping leading to a broadening in bandgap i.e., 3.72, and 3.5 eV direct and indirect bandgaps, respectively through ultra-violet visible spectrophotometry. PVD grown thin films indicated formation of clusters and irregular structures between the gaps and voids of micro-grains shown by field emission scanning electron microscopy. Rutherford back scattering spectroscopy expressed the remarkable thickness i.e., 615 nm with stronger signals for Cd, Co and S elements. Furthermore, the electrochemical analysis of the pristine and doped chalcogenide thin films done via cyclic, linear sweep voltammetry and chronoamperometry elucidated the excellent photo-response and functional stability and confirmed the potential of these films as future candidates for multitudinous photovoltaic and optoelectronic devices especially the utilization of [Co:Cd-(dtc)2]/SnO2 thin films in solar cell devices is expected to yield higher through put potentials and photo-currents if sandwiched between the active absorber layer and photo-electrodes.

Ultrasmall SnO2 directly grown on commercial C45 carbon as lithium-ion battery anodes for long cycling performance

Development of high-performance SnO2 anodes is hampered by its peculiar electrochemical behavior, characterized by two processes: conversion and alloying reactions. The conversion reaction being irreversible leads to specific capacities lower than theoretical, however rational design of nanosized SnO2 can mitigate this issue, though SnO2 low conductivity and electrode pulverization justify the need of carbon matrices. Some carbon structures proved to be strongly effective at laboratory-scale, but most are too expensive or complicated to obtain for scaling-up. Herein, we exploit the high concentration of oxide and carboxylic surface functional groups of C-NERGY™ Super C45 carbon black for one-pot synthesis of ultrafine SnO2 nanoparticles over the carbon surface. These functional groups accomplish the hydrolysis/oxidation of SnCl2, resulting in finely dispersed SnO2 nanoparticles (5 nm in average size) growth over C45. Presence of oxygen species on C45 surface, accessible to tin, prevent fast formation of Li2O, allowing to achieve high capacity and extreme electrode stability. The assembled cells with SnO2/C45 exhibit for more than 400 cycles the reversible capacity of 560 mA h g−1 per pure SnO2 (after subtracting C45 contribution) at 1C, demonstrating prolonged cycling operation thus providing an interesting opportunity for scalable production of stable and high-capacity battery anodes alternatively to graphite.

Hierarchical TiO2/AgBr core/shell microspheres with enhanced visible light photocatalytic activity

TiO2/AgBr core/shell microspheres have been successfully synthesized via a two-step solvothermal process. The TiO2 core (1.5 µm in average diameter) is coated with a shell (100 nm in average thickness) consisting of AgBr nanoparticles of 6 nm in average size. The composite nanomaterials demonstrate much stronger light absorbance, narrower bandgap, and lower recombination rate of photogenerated electron–hole pairs than both bare TiO2 microspheres and pure AgBr nanoparticles, which endue it with much enhanced photocatalytic activity. The as-prepared TiO2/AgBr photocatalyst exhibits excellent photocatalytic degradation performance towards methylene blue (MB) under visible light irradiation, and 92% MB could be degraded in 90 min, which is much higher than that of bare TiO2 (11%) and pure AgBr (52%). TiO2/AgBr core/shell microsphere photocatalyst also demonstrates good reusability, and the photocatalytic activity has no obvious decrease after five cycles. This study may provide a new insight into the design and synthesis of visible light photocatalytic materials.