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Selenylation Astragalus polysaccharides (Se-APS) was fabricated by an optimized microwave-assisted method. Their physicochemical properties, antioxidant capacities and selenium (Se) release rate under gastrointestinal conditions were determined. Se-APS with the highest Se content (18.8 mg/g) was prepared in 0.4 % nitric acid, under the microwave conditions of 90 min and 80 °C. FTIR and XPS spectra indicated that Se was bound to the polysaccharide chain in the form of O-Se-O and O-H···Se, and most of Se+4 was reduced to Se0. Meanwhile, the micromorphology of Se-APS became clusters, loose and porous, which decreased its hydrodynamic particle size and negative surface charges. Besides, Se-APS displayed strong scavenging capacities towards ABTS and superoxide anion free radicals than Na 2 SeO 3 , and showed higher Se release rate (12.52 ± 0.31 %) under intestinal fluid comparing with gastric fluid (3.14 ± 0.38 %) during 8 h in vitro digestion. The results provided efficient preparation method references for selenylation polysaccharides, and broaden the application fields of APS. [Display omitted] • The selenylation modification of APS by a microwave-assisted method was achieved. • The Se content under optimum Se-APS preparation condition was 18.8 mg/g. • The valence state of Se in Se-APS was composed of +4 and 0. • Se-APS had good ABTS and superoxide anion free radical scavenging capacities. • Se-APS had higher Se release rate (12.52 ± 0.31 %) under intestinal fluid in vitro. [ABSTRACT FROM AUTHOR]

We have successfully synthesized multi-layer graphene oxide and graphene oxide based magnetic nanocomposite (M/GO) by microwave-assisted modified Hummers' method for removal of toxic lead (Pb2+) and cadmium (Cd2+) ions from aqueous solution. The X-ray diffraction spectra of synthesized graphene oxide and M/GO confirm increased interlayer spacing along c-axis. Raman spectra revealed the good quality of synthesized GO and M/GO. The wrinkles were seen in the SEM images of synthesized graphene oxide. The presence of conjugated double bond (C C) and carbonyl (C O) were confirmed by using the UV–Vis spectroscopic spectra. Brunauer–Emmett–Teller (BET) analysis showed high (126 m2/g) surface area M/GO composite which accounts for large number of active binding sites for the adsorption of heavy metal ions. The adsorption studies revealed that Pb2+ ions were efficiently adsorbed on GO sheets. Interestingly, M/GO showed better adsorption for cadmium ions. Addition of stock solution of Pb2+ and Cd2+ ions to M/GO solution, removal of M/GO containing Pb2+, and Cd2+ ions using Neodymium magnet. [Display omitted] [ABSTRACT FROM AUTHOR]

ZnFe 2 O 4 nanoparticles/S, N co-doped carbon nanotube composites were prepared by a microwave-assisted method with low cost, low energy consumption and easy commercialization. Through the strategies of nanosizing, heteroatom doping, and compounding with advanced carbon materials, the inherent disadvantages of poor electronic conductivity and low ion diffusion rate of transition metal oxides are improved, and the volume expansion of ZnFe 2 O 4 during cycling is slowed down by using carbon nanotubes with high specific surface and high mechanical strength as the material support skeleton, which enhances the cycling stability of the material. At a current density of 0.1 A g−1, the specific capacity of 716.23 mAh g−1 was maintained after 100 charge/discharge cycles. The charge/discharge cycle at a high current of 2 A g−1 still has a specific capacity of 309.90 mAh g−1. • Carbon nanotubes provide a nucleation site for Znfe 2 o 4 and reduce its size. • Carbon nanotubes reduce material agglomeration and improve cycle stability. • The introduction of S and N atoms creates more defects and active sites. • ZnFe2O4/SNCNT maintain a reversible capacity of 716.23 mAh g-1 after 140 cycles. [ABSTRACT FROM AUTHOR]

• Ni/CeO 2 catalysts were prepared by co-precipitation with different heating treatments. • Heating treatments included microwave, hydrothermal and evaporation. • Performance of Ni/CeO 2 catalysts was evaluated in a packed-bed reactor at 200–500 °C. • Reduction temperatures of Ni species were affected by heating treatments. • Superior performance of Ni/CeO 2 −MW was due to the uniform dispersion of Ni on CeO 2. In thid study, Ni/CeO 2 catalysts were prepared by a one-step co-precipitation of nickel and cerium salts in a NaOH solution treated by different heating methods including microwave (MW), hydrothermal (HM) and evaporation (EP). With TEM observation, the co-precipitation provided the catalysts containing a highly crystalline CeO 2 of a (111) plane structure with d -spacing of 3.15–3.24 Å. The obtained CeO 2 nanoparticles exhibited a pseudo-spherical shape with a size range of 10.8–12.1 nm. Based on HR-TEM analyses, NiO nanoparticles with a large size range of 48.8–51.2 nm were found to be incorporated within the CeO 2 nanostructure. By N 2 sorption measurement, all Ni/CeO 2 catalysts possessed a mesoporous characteristic with a specific surface area range of 70.5–75.7 m2/g and an average pore diameter of 30 nm. XRD results revealed that NiO species could be completely transformed into Ni0 species by the H 2 reduction process. XPS analyses further confirmed the presence of Ni0 species with a prominent peak at an energy bandgap of 852.6 eV. Hydrogen temperature-programmed reduction (H 2 -TPR) confirmed that α and β peaks of NiO species were completely reduced at a temperature lower than 500 °C. The Ni/CeO 2 catalyst prepared by MW method exhibited a higher strong metal-support interaction (SMSI) between Ni and CeO 2 revealed by H 2 consumption results. The Ni/CeO 2 catalysts prepared by MW, HM, EP methods exhibited the CO 2 methanation activity with TOF of 13.6, 10.8 and 5.8 s−1, which could be correlated with the Ni crystallite sizes of 42.2, 50.5 and 52.8 nm, respectively. All prepared Ni/CeO 2 catalysts exhibited the stable catalytic performances with a negligible drop in CO 2 conversion and CH 4 selectivity over 72 h-time-on-stream test. In comparison, the MW method with a rapid and uniform heating under autogenous pressure could result in the Ni/CeO 2 catalyst with the superior catalytic activities due to the higher dispersion of Ni. [Display omitted] [ABSTRACT FROM AUTHOR]

The combination of metallic and carbon components offers tremendous advantages in the development of advanced composites for electromagnetic wave absorption (EMWA) applications. Herein, hollow (NiCo) x /(MnO) y /C microspheres (MSs) possessing hierarchically porous structures were successfully synthesized via a facile microwave-assisted method followed by a carbonization step. The EMWA performance of the (NiCo) x /(MnO) y /C MSs in the K-band region could be tuned and optimized by adjusting the NiCo/Mn molar ratio, with a NiCo/Mn ratio of 1:1 affording the best EMWA performance. The NiCo/MnO/C MSs exhibited a minimum reflection loss value of -32.3 dB (at 21.4 GHz) and an effective absorption bandwidth (EAB, RL ≤ −10 dB) of 8.33 GHz (from 18.17-26.5 GHz) at a thickness of only 1.0 mm in the K band. The excellent EMWA performance of the (NiCo) x /(MnO) y /C MSs composites can be attributed to a strong EMW attenuation capacity and good impedance matching, which arise through the synergistic action of the components (NiCo alloy, MnO and C) and hierarchical pores. Image 1 [ABSTRACT FROM AUTHOR]

[Display omitted] • NiFe 2 O 4 -CoFe 2 O 4 nanocomposites (NF-CF NCs) were synthesized by microwave-assisted method. • NF-CF NCs were characterized by structural, morphological and optical studies. • NF-CF NCs showed promising photocatalytic activity against Rose Bengal and Methylene blue dyes under visible light irradiation. • Photoelectrochemical hydrogen production was tested in the presence NF-CF NCs. Microwave radiation assisted method is emerged as a promising method due to its environmental friendliness, less time and no need toxic or harsh reagents. Herein, we report the synthesis of a NiFe 2 O 4 -CoFe 2 O 4 nanocomposites by microwave radiation assisted method and its characterisation using various methods. X-ray Diffractogram (XRD) studied revealed the spinel cubic structure of the NiFe 2 O 4 -CoFe 2 O 4 nanocomposites having an average crystallite size of 34 nm. Tetrahedral (594 cm−1) and octahedral (397 cm−1) sites of NiFe 2 O 4 -CoFe 2 O 4 are identified by Fourier Transform Infrared (FTIR) spectroscopy as it is having the typical vibrational frequencies. UV–Visible diffuse reflectance (UV–Vis DRS) spectrum indicated that optical bandgap is less for nanocomposites compared to individual components. Transmission electron microscopy (TEM) images show the spherical nature of the nanocomposites. The photocatalytic degradation study of microwave-assisted NiFe 2 O 4 -CoFe 2 O 4 nanocomposites is investigated under visible light irradiation against the Rose Bengal and Methylene blue dyes. The developed nanocomposites exhibited enhanced photoelectrochemical hydrogen due to higher charge separation and faster charge transfer at the interface. [ABSTRACT FROM AUTHOR]

Abstract In this study, graphene oxide (GO) was eco-friendly and reduced with microwave-assisted method to form reduced graphene oxide (rGO). Two components of nanocomposite of rGO and Ruthenium oxide (RuO 2) (rGO/RuO 2) and a ternary components of nanocomposite of rGO, RuO 2 and polyvinylcarbazole (PVK) (rGO/RuO 2 /PVK) were synthesized via in-situ polymerization technique. These nanocomposite materials were characterized by Fourier-transform infrared spectroscopy-attenuated transmission reflectance (FTIR-ATR), scanning electron microscopy (SEM), and energy-dispersive X-ray analysis (EDX), thermal-gravimetric (TGA-DTA) analysis, transmission electron microscopy (TEM), X-ray diffraction (XRD), and BET surface analysis. Supercapacitor device performances were taken by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS) used as two electrode configuration. The highest specific capacitance (C sp) was obtained as C sp = 2698 F/g at 2 mV/s for rGO/RuO 2 /PVK nanocomposite at initial feed ratio of [rGO] o /[RuO 2 ] o /[9-VK] o = 1:1:5. Besides, the highest energy and power density values were obtained as E = 17.711 Wh/kg and P = 2684.36 W/kg for rGO/RuO 2 nanocomposite. Ragone plots were drawn to observe energy and power density of supercapacitor devices. Stability tests were examined by CV method for 1000 cycle. Graphical abstract Image 1 Highlights • The highest specific capacitance was obtained for rGO/RuO 2 /PVK nanocomposite. • LR 1 (QR 2 (CR 3)) circuit model evaluation was performed for rGO/RuO 2 /PVK nanocomposite. • Supercapacitor device performances were applied for rGO/RuO 2 /PVK nanocomposite. [ABSTRACT FROM AUTHOR]

Highlights • BiF 3 /BiOBr with higher photodegradation ability was synthesized by a fast and stable microwave-assisted method. • The O 2 − and h+ were the main active species in the oxidation of RhB. • Improvement of photocatalytic activity was owed to high photoelectron-hole separation efficiency. Abstract Novel BiF 3 /BiOBr heterojunction photocatalysts were prepared from a fast and stable microwave-assisted method, and characterized by X-ray diffractometry, X-ray photoelectron spectroscopy, scanning electron microscopy, ultraviolet-visible spectroscopy and fluorescence spectroscopy. The photocatalytic activity of BiF 3 /BiOBr heterojunctions under light irradiation was significantly higher than pure BiOBr or BiF 3 , and was maximized at the Br:F molar ratio of 1:1, as the targeted 20 mg/L Rhodamine B (RhB) solution was completely degraded within 40 min. This was mainly because the unique BiF 3 /BiOBr heterojunction formed during photocatalytic degradation accelerated the photoelectron and hole separation, effectively enhanced the quantum efficiency, and thereby strengthened the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Abstract The Ni-rich layered oxide (NLO) cathode materials play a key role in developing high-energy-density lithium ion battery (LIB) for wide scale deployment of clean transportation technologies. However, surface reconstruction from a layered structure to a mixed spinel/rock-salt structure during charge/discharge cycles is related to the severe voltage decay and capacity fading of the stoichiometric NLO cathode materials, thus thwarting the practical implementation. Herein, we report a heterostructured NLO cathode that tackles the structural degradation and related voltage decay problems. The efficient internal "incore" volumetric heating by direct coupling of microwave energy induces formation of Ni, Co-rich core and Al-rich shell. As a result of the encapsulation of the atomically ordered NiAl 2 O 4 after heat treatment, the solid/electrolyte interphase and surface structure of NLO cathode remains stable. By applying this NiAl 2 O 4 /NLO heterostructured material as a cathode, we demonstrate its robustness in suppressing the voltage decay (0.8% after 100 cycles) during high-voltage cell operation. Rather than the typical modifications, our work explores a more efficient structure engineering process for applications in nano-/micro-manufacturing transition-metal based electrode materials and sheds light on developing high-performance LIB in the near future. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Cu/Fe-AO-PAN fiber was prepared by a facile and rapid microwave-assisted method. • The fiber showed nearly 100% of PNP removal rate under visible light irradiation. • The fiber exhibited good pH tolerance, photocatalytic activity and stability. Abstract A visible-light responsive Cu-Fe bimetallic amidoxime-modified polyacrylonitrile (denoted by Cu/Fe-AO-PAN) fiber was prepared using a facile and rapid microwave-assisted synthesis method. Several microscopic and spectroscopic techniques were adopted to characterize the morphology, structure, thermal and optical properties of the Cu/Fe-AO-PAN fiber. The results indicated that Cu2+ and Fe3+ ions were successfully coordinated with AO-PAN without causing distinct damage to the fiber and that chelation with metal ions extended the light absorption into the visible-light region. P-nitrophenol (PNP) was used to investigate the photocatalytic performance of the Cu/Fe-AO-PAN fiber in a photo-Fenton system under visible light irradiation. Various parameters that affected PNP removal were discussed, including the microwave heating temperature, irradiation time, Cu/Fe molar ratio, and photo-Fenton reaction conditions, such as the pH, H 2 O 2 concentration and fiber dosage. Under the optimal conditions, a PNP removal rate of approximately 100% was achieved within 150 min under visible light irradiation. The bimetallic Cu/Fe-AO-PAN exhibited improved pH tolerance, photocatalytic performance and stability compared to the monometallic Fe-AO-PAN fiber. In addition, a mechanism for PNP degradation induced by the Cu/Fe-AO-PAN fiber in the photo-Fenton system under visible light irradiation was proposed. [ABSTRACT FROM AUTHOR]

Abstract In this work, an eco-friendly and convenient microwave-assisted synthesis technique was applied in the entire experiment course. The first obtained graphene-Ni composite possess an unsatisfactory microwave absorption capacity due to unbalanced matching nature. Then a sulfurization process was tried at different temperatures to convert Ni into NiS/Ni 3 S 2 , and an innovative graphene-NiS/Ni 3 S 2 composite with a hierarchical architecture was fabricated under the condition of microwave irradiation. The investigation into microwave absorbing performances manifests that the absorption property of graphene-Ni can be obviously improved by sulfurization method. The results show, compared with graphene-Ni, the hierarchical-architecture graphene-NiS/Ni 3 S 2 composites generated at 150 ℃ (S-150) possess excellent absorbing ability with a maximum RL as strong as − 55.1 dB at 6.0 GHz with a thickness of 2.7 mm, and the effective bandwidth covers 8.6 GHz from 2.8 to 11.4 GHz with thickness varies in 1.5–4.5 mm range. The enhanced performances for S-150 mainly derive from the synergy of superior impedance matching character, high attenuation, dielectric loss and plenteous interface polarizations. [ABSTRACT FROM AUTHOR]

Microbial fuel cells (MFCs) are being recognized as a promising solution for sustainable energy generation and wastewater treatment. Despite their potential, MFCs face certain challenges that must be overcome, such as the problem of low power output caused by inefficient extracellular electron transfer (EET). In this study, we develop a nanoporous CoC x /Co@CC composite anode using microwave-assisted and high-temperature calcination methods to enhance EET efficiency and bacterial adhesion in MFCs. Compared with pure carbon cloth (CC) anodes, MFCs with CoC x /Co@CC anodes exhibit a 1.24-fold increase in power density, with a maximum output of 2693 mW m−2. The improved performance can be attributed to the lower charge transfer resistance (R ct) and higher redox activity of the CoC x /Co@CC anode. Cobalt's multiple valence states enhance its ability to transfer electrons between microorganisms and electrodes, ultimately increasing the overall redox activity. The CoC x /Co@CC anode also promotes the growth and enrichment of exoelectrogens, with Geobacter being enriched up to 75 % at the anode, compared with 46 % at the CC electrode. These findings demonstrate the potential of CoC x /Co@CC anodes for improving the EET efficiency of MFCs, which can have significant implications for sustainable energy and wastewater treatment. [ABSTRACT FROM AUTHOR]

A series of lanthanide tetrakis complexes C n mim[Ln(tta) 4 ] where Ln3+: Eu3+ and Gd3+, C n mim: imidazolium-based counterions (n from 3 to 8) and tta: thenoyltrifluoroacetonate were synthesized by a one-pot method. The C n mim[Ln(tta) 4 ] complexes are thermostable up to 210 °C and present an isomorphic-like character for the complexes with n = 5, 6, and 7. The phosphorescence spectral profile of the C n mim[Gd(tta) 4 ] complexes showed intense emission broadbands, in which the barycenters are slightly shifted to energies from the 18,950 to 18,450 cm−1 range. The C n mim[Eu(tta) 4 ] complexes in solutions of the corresponding [C n mim]Br ionic liquids show similar emission spectral profiles as their corresponding in the solid state, indicating that the coordination polyhedron does not undergo a significant variation when the chemical environment is changed. Relatively high values of the intensity parameter Ω 2 in both media are presented. The Ω 4 values of the complexes in solutions of ionic liquids are also similar, reinforcing that there are small changes in the polyhedral coordination from the solid state to the ionic liquid solution. The series presents high intrinsic emission quantum efficiencies, 90 % ≥ Q E u E u ≥ 53 %. In addition, theoretical calculations on the intramolecular energy transfer (IET) reveal the participation of the 7F 0 →5D 1 and 7F 1 →5G 2 transitions for the IET via S 1 while the IET via T 1 state is dominated by the 7F 0 →5D 1 and 7F 1 →5D 0 transitions. Therefore, due to their high luminescent features, these Eu3+ tetrakis complexes are potential candidates to be applied as optical markers in the solid-state or even in ionic liquid solutions. • Lanthanide tetrakis complexes with imidazolium as counterions are stable and have high thermal stability. • A shift in the T 1 state was found in the [C n mim][Gd(tta) 4 ] series (n = 3 to 8). • Intramolecular energy transfer rates from T 1 to Eu3+ were calculated and show different behaviors according to the shift in the T 1 state. • The Eu3+ tetrakis complexes have high intrinsic emission quantum efficiencies in both solid-state and ionic liquid solutions. [ABSTRACT FROM AUTHOR]

A sustainable method is employed to remove polycyclic aromatic sulphur heterocycles (PASHs) from fuels by using a series of high surface area nanoporous adsorbents synthesized from polycyclic aromatic hydrocarbons (PAHs). The hypercrosslinking of PAHs has been used to synthesize high surface area (SA BET of 620–1565 m2 g−1) nanoporous polymeric materials via a microwave assisted method. The adsorbent poly-naph (highest SA BET , i.e., 1565 m2 g−1) display best performance for desulphurization of fuels from batch to fixed bed column mode. In batch mode, the adsorption capacity of 12.1 (up to 9 ppm sulphur) and 8.9 mgS g−1 (up to 43 ppm sulphur), has been estimated for model (100 ppm sulphur) and real fuels (110 ppm sulphur), respectively. Furthermore, from ultra-low sulphur model (10 ppm sulphur) and real fuel (9 ppm sulphur), the adsorption capacity of 16.1 (up to 0.3 ppm sulphur) and 10 mgS g−1 (up to 3 ppm sulphur) has been estimated. In fixed-bed column mode, the high concentrated model and real fuel have been desulphurized to final concentration of 1 and 12 ppm, respectively. While, at low concentrations, the final concentration of 100 ppb and 1 ppm is achieved for model and real fuels, respectively. The adsorption mechanism revealed that π-electron density in the polymeric framework plays prominent role in the adsorption process apart from high surface area. This approach to control carcinogenic aromatic pollutants like PAHs and PASHs can be sustained over time through technological advancement, financial assistance and governmental regulation. [Display omitted] • Polycyclic aromatic hydrocarbon pollutants are used to develop adsorbents. • A rapid microwave assisted 60 min synthesis is used. • Desulphurization of fuel at high (∼100 ppm) and low (∼10 ppm) sulphur concentration. • Batch to fixed-bed column mode desulphurization of model and real fuels. • Polycyclic aromatic sulphur heterocycles are removed by developed adsorbents. [ABSTRACT FROM AUTHOR]

ZnO, CdO nanomaterial were utilized for the degradation of Alizarin Red dye photocatalytically under visible light illumination. Zno photocatalyst was prepared by the hydrothermal method at a temperature of 160 °C and CdO synthesized by the microwave-assisted hydrothermal method at a temperature of 140 °C.Synthesized nanomaterial was characterized by XRD, SEM, TEM, UV–vis spectroscopy and PL. The photocatalytic degradation of Alizarin Red (AR) dye was carried out utilizing prepared photocatalyst irradiated with 60 W Tungsten light source with the fixed dose of catalyst on standard AR dye and studied its Kinetic analysis of photodegradation on Alizarin Red dye and conclude the efficiency of ZnO and CdO nano photocatalyst at the same condition. [ABSTRACT FROM AUTHOR]

In this study, CdO, NiO, and CdO-NiO nanocomposites (NCs) were synthesized and investigated by X-ray diffraction (XRD), scanning electron microscopy, and Fourier transform-infrared spectroscopy. XRD detected cubic structures with average crystallite sizes of 45 nm for CdO, 25 nm for NiO, and 30 nm for CdO-NiO. The band gap was estimated based on the ultraviolet–visible spectra. The near band edge emission was determined according to the luminescence spectrum. The antibacterial activities were tested against seven foodborne pathogens and the zones of inhibition with the Gram-negative bacterium Bacillus subtilis measured as 30 mm with CdO, 20 mm NiO, and 27 mm with CdO-NiO. The death of the bacterial cells was confirmed by confocal laser scanning microscope analysis. Cytotoxicity assays indicated the non-toxic effects of the NCs on normal healthy red blood cells. Furthermore, the in vitro cytotoxic effects of the CdO, NiO, and CdO-NiO NCs were examined using the human MCF-7 breast cancer cell line based on 3-[4,5-dimethylthiazol-2-yl]2,5-diphenyltetrazolium bromide assays with normal mouse embryonic fibroblasts (NH3T3) under identical conditions. [ABSTRACT FROM AUTHOR]

In the report, microwave-assisted and hydrothermal methods were adopted respectively to produce nitrogen doped carbon dots (N-CDs) using ginkgo fruits as the sole carbon source without additional surface passivation agents. The differences between these two N-CDs were compared in luminescence properties, particle sizes and morphologies. The TEM images showed that both microwave-assisted N-CDs (M-N-CDs) and hydrothermal N-CDs (H-N-CDs) were well dispersed, and the morphology of H-N-CDs was more uniform. The fluorescence results indicated the H-N-CDs possessed better fluorescence emission characteristic. Thus, the H-N-CDs with better luminescence properties were characterized by FT-IR, XPS, fluorescence and UV–Vis spectroscopy. Also, the stability and cytotoxicity of H-N-CDs synthesized by ginkgo fruits as the fluorescent probes were studied. Eventually, the H-N-CDs were applied in cell imaging using HeLa cells and KYSE410 cells as the cell models. [ABSTRACT FROM AUTHOR]

A new coordination polymer {[Zn(μ 3 -ppda)(H 2 O)(μ-bpa)Zn(μ-ppda)(μ-bpa)]·4H 2 O} n ( 1 ) (ppda = 1,4-phenylenediacetate, bpa = 1,2-bis(4-pyridyl)ethane) has been synthesized by microwave-assisted reaction and characterized by elemental analysis, IR spectroscopy, single-crystal and powder X-ray diffractions. The asymmetric unit of 1 consists of two Zn(II) ions, two bpa ligands, two ppda ligands, one coordinated and four non-coordinated water molecules. In 1 , ppda 2− anions are linked the adjacent Zn(II) centers to generate 1D double-stranded chains. These chains are connected into 2D sheets by the bridging bpa ligands. Atomically detailed modeling was performed to compute single and binary component adsorption isotherms of H 2 , CO 2 , CH 4 and N 2 in complex 1 . Results showed that 1 exhibits a high adsorption selectivity towards CO 2 due to its high affinity for CO 2 . Results of this study will be helpful to guide the microwave-assisted reaction of coordination polymers to design promising adsorbents for gas storage and gas separation applications. The luminescent property of 1 and the selective removal of dyes in 1 have been also discussed. Results showed that 1 can be a potential candidate for luminescence applications and can selectively adsorb methylene blue (MB) dye molecules. [ABSTRACT FROM AUTHOR]

Hierarchically nanostructured Shuttle-like aragonite mesocrystals have been successfully achieved in a water/ethylene glycol (EG) binary solvent system by a facile microwave-assisted method without using any other organic additives. The synthesized products were characterized by a wide range of techniques including X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and nitrogen physisorption analysis. The effects of the ratio of EG to water, and calcium sources on the formation of the special structured aragonite were studied systematically. The results indicate that the cooperation of EG and acetate ions are indispensable to the formation of shuttle-like aragonite mesocrystals, and a plausible oriented attachment formation mechanism is proposed. Moreover, the removal ability of the hierarchical aragonite mesocrystals for La(III) was also tested. Batch experiments reveal that the aragonite possesses excellent removal efficiency to La(III), suggesting that the shuttle-like aragonite mesocrystals can be potentially applied in the removal of rare earth elements (REEs) entering the water environment. [ABSTRACT FROM AUTHOR]

• Microwave-assisted green synthesis has been used to prepare TiO 2 /rGO-NS composite. • The as-prepared nanomaterials offered a high electrochemical surface area. • TiO 2 /rGO-NS composite shows less charging time and high current density. • The as-prepare material delivers better capacitance retention after 1000 cycles at 10 Ag−1. • The synthesized material can be used in supercapacitor electrodes. The present study deals with synthesizing rGO nanosheets and TiO 2 nanoparticles by a green method using aloe vera and gram seeds, respectively, while a simple microwave-assisted approach has been used to prepare the TiO 2 /rGO nanosheets composite. The as-prepared materials were investigated via different analytical techniques such as SEM, TEM, X-ray diffraction, Fourier transform infrared, X-ray photoelectron spectroscopy and Raman spectroscopy. The TiO 2 /rGO-NS composite showed a sheet-like nature and was deposited on a carbon cloth substrate using Nafion binder and used as the working electrode (cathode). The electrochemical properties of the as-prepared materials were studied using cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. The TiO 2 /rGO-NS composite fabricated on the carbon cloth substrate shows a relatively higher specific capacitance with lower charge transfer resistance. The TiO 2 /rGO-NS composite coated carbon cloth cathode shows a maximum specific capacitance (599.9 Fg−1) and energy density (83.31 Whkg−1) at a current density of 1 Ag−1. [ABSTRACT FROM AUTHOR]

Sb 2 O 3 /reduced graphene oxide (RGO) composites were prepared through a facile microwave-assisted reduction of graphite oxide in SbCl 3 precursor solution, and investigated as anode material for sodium-ion batteries (SIBs). The experimental results show that a maximum specific capacity of 503 mA h g −1 is achieved after 50 galvanostatic charge/discharge cycles at a current density of 100 mA g −1 by optimizing the RGO content in the composites and an excellent rate performance is also obtained due to the synergistic effect between Sb 2 O 3 and RGO. The high capacity, superior rate capability and excellent cycling performance of Sb 2 O 3 /RGO composites demonstrate their excellent sodium-ion storage ability and show their great potential as electrode materials for SIBs. [ABSTRACT FROM AUTHOR]

In the present work, a microwave-assisted one-pot method was applied for preparation of the ZnO/AgI nanocomposites. One-pot, large-scale, and short preparation time are main advantages of this method. Photocatalytic activity of the nanocomposites in degradation of rhodamine B under visible-light irradiation is remarkably depended on mole fraction of AgI and the superior activity was seen for the nanocomposite with 0.342 mol fraction of silver iodide. The degradation rate constant over this nanocomposite is about 10-fold higher than that of the ZnO nanostructures. Photoluminescence spectra confirmed that separation of the charge carriers in the nanocomposites is more intensive than the ZnO nanostructures. Furthermore, it was observed that the microwave irradiation time, calcination temperature, and scavengers of the reactive species have considerable influence on the degradation reaction. More importantly, the photocatalyst retains about 80% of its activity after using for five cycles. [ABSTRACT FROM AUTHOR]

Copper sulfide nanoflower/reduced graphene oxide (CuS/rGO) composite is synthesized using Cu(NO 3 ) 2 , thiourea (Tu) and graphene oxide (GO) powers as the precursor by an ultrafast microwave-assisted hydrothermal method. The electrochemical performances of CuS/rGO composite as anode material of Lithium ion batteries (LIBs) are studied both in ether-based (LiTFSI in DOL/DME) and carbonate-based electrolytes (LiPF 6 in EC/DMC). The results reveal that CuS/rGO composite exhibits excellent electrochemical Li-storage properties. The reversible capacity of 422 mA h g −1 and 390 mA h g −1 at a current density of 100 mA g −1 after 70 cycles is obtained in both electrolytes, respectively. Even after 200 charge-discharge cycles at 500 mA g −1 in ether-based electrolyte, the composite delivers a good discharge capacity of 390 mA h g −1 with high capacity retention ratio of 96.7%. The good electrochemical performances of CuS/rGO can be attributed to the synergistic effect of the CuS nanoflower and rGO. Briefly, the introduction of rGO can improve the electronic conductivity of the composite, effectively immobilize the CuS and inhibit the dissolution of the polysulfide intermediates generated during the charge-discharge process. [ABSTRACT FROM AUTHOR]

This work investigates ethanol electrooxidation on Pt/C, Pt x Rh y /C, Pt-SnO 2 /C, and Pt x Rh y -SnO 2 /C catalysts synthesized by the Pechini and microwave-assisted polyol methods. The catalysts are characterized by energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), and X-ray diffraction (XRD) techniques. The electrochemical properties of these electrode materials are examined by cyclic voltammetry and chronoamperometry experiments in acid medium. The products obtained during ethanol electrolysis are identified by high performance liquid chromatography (HPLC). The adsorbed intermediates are evaluated by an in situ reflectance Infrared Spectroscopy technique combined with cyclic voltammetry. Catalysts performance in a direct ethanol fuel cell (DEFC) is also assessed. The electrical performance of the electrocatalysts in a single DEFC at 80 °C decreases in the following order Pt 70 Rh 30 SnO 2 > Pt 80 Rh 20 SnO 2 > Pt 60 Rh 40 SnO 2 ∼ PtSnO 2 > Pt x Rh y ∼ Pt, showing that the presence of SnO 2 enhances the ability of Pt to catalyze ethanol electrooxidation. [ABSTRACT FROM AUTHOR]

ZnS nanoparticles embedded in reduced graphene oxide (RGO) were prepared via a facile microwave-assisted method and applied as anode materials of sodium-ion batteries (SIBs). The as-prepared composites exhibit excellent sodium storage properties. A maximum specific capacity of 481 mAh g −1 at the specific current of 100 mA g −1 can be achieved after 50 cycles by optimizing the RGO content in the composites. The improved sodium-ion storage ability can be ascribed to the enhanced specific surface area and increased electric conductivity due to the introduction of RGO and the decreased size of ZnS particles which can shorten the pathway of sodium-ion diffusion and facilitate the reversible Na + diffusion kinetics. [ABSTRACT FROM AUTHOR]

Layered nickel sulfide (NS)-reduced graphene oxide (RGO) composites are prepared via a simple microwave-assisted method and subsequent annealing in N 2 /H 2 atmosphere. A detailed array of characterization tools are used to study their morphology, structure and electrochemical performance. It was found that these composites exhibit significantly improved sodium-ion storage ability as compared with pure NS under galvanostatic cycling at a specific current of 100 mA g −1 in a potential limitation of 0.005–3.0 V. Furthermore, the composite with the RGO content of 35 wt.% achieves a high maximum reversible specific capacity of about 391.6 mAh g −1 at a specific current of 100 mA g −1 after 50 cycles. These results prove that NS-RGO composites are highly promising when applied directly as anode materials in sodium-ion batteries. [ABSTRACT FROM AUTHOR]

Microwave assisted Bi 2 Se 3 nanoparticles were synthesized from five different solvents DMF, EG, EG + H 2 O, EDA + dil.HNO 3 and N 2 H 4 + H 2 O + Ethanol. The influence of solvents on purity of the compound was analysed by using X-ray diffraction patterns. The result indicates pure rhombohedral Bi 2 Se 3 nanoparticles formed for N 2 H 4 + H 2 O + Ethanol. The presence of vibrational bands in the range of 400–800 cm − 1 is confirmed the formation of Bi 2 Se 3 . The maximum optical absorption observed around 450 nm and the band gap values are found in the range of 1.5 eV–2.17 eV for all the solvents. The nanostructure of the Bi 2 Se 3 particles change with solvents. From the experimental results, the solvent N 2 H 4 + H 2 O + Ethanol produces pure nanosize Bi 2 Se 3 particles under the microwave assisted method. [ABSTRACT FROM AUTHOR]

Tetraethylenepentamine-functionalized Rosa canina -L fruits activated carbon (TEPFRCA) was synthesized by microwave-assisted method for the fast adsorption and rapid removal of Malachite green (MG) from the solvent phase. The morphological and anatomical characterization of developed adsorbent was carried out using various analytical techniques such as FT-IR and FE-SEM. The impact of various influential parameters such as contact time (1–60 min), initial metal ion concentration (25–65 mg/L), temperature (298–333 K), adsorbent dose (0.001–0.025 g) and initial pH (1–8) of the solution was carried out using a batch adsorption method. The adsorption kinetic and equilibrium data process follows pseudo-second-order reaction kinetics (R 2 > 0.99) and the maximum adsorption capacity for TEPFRCA was 333.3 mg/g at 298 K. The whole process of adsorption of MG dye on to the developed adsorbent i.e. TEPFRCA was found to be spontaneous and endothermic under standard conditions. [ABSTRACT FROM AUTHOR]

As an energy storage system, pseudocapacitors aim to combine the high power density with the high energy density, because their performance is mainly determined by surface reactions and structures. In this work, NiS nanoparticles are synthesized by microwave-assisted method and used as pseudocapacitor electrode. The NiS electro-active material demonstrates excellent electrochemical performance with high specific capacitance (845 F g −1 at current densities of 1 A g −1 ), low resistance and excellent cycling stability. To reveal the original reasons of the excellent performance, first-principles density functional theory (DFT) calculations are performed to provide atomic insight on how the electrolyte interacts with NiS nanoparticles electrode. According to the results, two sites are found energy suitable for absorbing hydroxyls on the Ni-terminal surface and have the electron transfer between hydroxyls and Ni atom, which reveals the position of the redox reaction. The density of the states of NiS (0 0 1) surface exhibits metallic, giving an explanation for low resistance and high rate capacitance. The NiS nanoparticles show their potential for pseudocapacitor materials and the atomic insight provides guidance for understanding and improving the performance of the NiS electrode materials. [ABSTRACT FROM AUTHOR]

Spent coffee grounds, an abundant daily waste, were utilized to produce P, N co-doped C (PNDC) by a novel microwave-assisted method employing ammonium polyphosphate as the only other reactant. Different PNDCs (namely PNDC-1, PNDC-2 and PNDC-3) were synthesized by varying the ratio of spent coffee grounds to ammonium polyphosphate. The synthesized materials were found to contain spherically shaped particles as evidenced from scanning electron microscopy. X-ray photoelectron spectroscopy revealed PNDCs to contain P and N in addition to C and O. PNDC-3 was discovered to possess a surface area of 999.64 m 2 g −1 with the presence of micropores, mesopores and macropores. PNDCs exhibited high specific capacitance values in acid and alkaline conditions with PNDC-3 exhibiting the highest specific capacitance value of 286 F g −1 in 1 M H 2 SO 4 . Also, PNDC-2 was observed to be highly stable under acidic and alkaline conditions with continuous cycling. [ABSTRACT FROM AUTHOR]

LaPO 4 nanopowders doped with 1, 2… 10, 11, 15 and 20 mol% Tb 3+ have been prepared by the microwave-assisted method. Transmission electron microscope (TEM) images indicated that the nanopowders are composed of nanorods. X-ray diffraction (XRD) analysis showed that the prepared nanorods exhibit hexagonal crystal structure and the diffraction peaks were shifted towards the higher 2 θ angle side with increasing Tb 3+ dopant concentration. Raman scattering measurement found out that some of scattering lines were shifted and broadened to higher wavenumber side with increasing Tb 3+ concentration. It is discovered that the photoluminescence (PL) of Tb 3+ ions results from the radiative intra-configurational f–f transitions that occur from the 5 D 4 exited state to the 7 F J ( J =0,1–6) ground states; the photoluminescence excitation (PLE) of Tb 3+ ions takes place from the 7 F 6 ground state to the 5 D J ( J =0,1–4), 5 L 10 , 5 G J ( J =2–4), 5 H J and 5 I J exited states. It was observed that the photoluminescence intensity reached a maximum in the samples doped with 15 mol% Tb 3+ . Double-exponential decay of the 5 D 4 → 7 F 5 emission was observed with lifetimes of ~5 ns and 6.35 ms. [ABSTRACT FROM AUTHOR]

Microwave-assisted methods have been frequently used in many processes owing to their numerous advantages such as performing fast, efficient and homogenous processes and reducing side reactions. In view of these benefits, in this study it was purposed to produce bone-like hydroxyapatite (HA) by inducing biomimetic process with microwave-irradiation. This is why, concentrated body fluid (SBF) i.e. 10×SBF-like solution was used and it was precipitated in different microwave powers i.e. 90 W, 360 W, 600 W, and 1200 W and in different exposure times. For comparison, precipitation process was also carried out at room temperature for 6 h and at 80 °C for 1 h. The obtained HA structures were characterized by appropriate instrumental techniques. As a result, microwave-induced precipitation at 600 W for 9 times 30 s was determined as the optimum condition for the production of HA which has similar properties to the cortical bone. At this condition, B-type HA with 9.22% (wt.) carbonate content, 1.61 Ca/P molar ratio and amorphous structure was obtained easily, rapidly and efficiently. So, this is the first time microwave technology has been used to precipitate HA from SBF solution. [ABSTRACT FROM AUTHOR]

CdO–ZnO nanocomposite was prepared by microwave-assisted method and characterized by X-ray crystallography (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FT-IR). It exhibits hexagonal cubic structure with an average crystallite size of 27 nm. From the UV–Vis spectra, the bandgap is estimated as 2.92 eV. The fluorescence spectrum shows a near band edge emission at 422 nm. In addition the antibacterial activity of CdO–ZnO nanocomposite was carried out in-vitro against two kinds of bacteria: gram negative bacteria (G −ve) i.e. Escherichia coli , Pseudomonas aeruginosa , Klebsiella pneumoniae and gram positive bacteria (G +ve): Staphylococcus aureus , Proteus vulgaris and Bacillus spp. This study indicates the zone of inhibition of 40 mm has high antibacterial activity towards the gram positive bacterium S. aureus . [ABSTRACT FROM AUTHOR]

We report a microwave-assisted method to synthesize truncated hexagonal pyramid (THP) tungsten carbide with 5nm in size on graphene sheets (WCTHP/G) for the first time. The high-resolution transmission electron microscope (HRTEM) and high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) analysis confirm that the WCTHP nanoparticles are dominated by (01 1 ¯ 0), (10 1 ¯ 0) and (1 1 ¯ 00) facets with a preferred orientation of [0001]. The Pt loaded WCTHP/G materials show high activity and extremely high stability in electrocatalysis. This method can be developed as a general strategy for synthesizing high surface area, nanostructured transition metal carbides (TMCs) and utilizing them as active and low-cost catalysts or catalyst supports in a broad range of sustainable energy technologies. [ABSTRACT FROM AUTHOR]

Real-time monitoring of dopamine (DA) levels, a critical neurotransmitter involved in motor function and blood pressure regulation, requires more sensitive and selective sensors over a dynamic concentration range. The immense need to build highly efficient catalysts has always been at the forefront of electrochemical detection research toward DA. Herein, we design and synthesis an iron carbides-based heterostructure composite (Fe/Fe 3 C@CNT) by the introduction of microwave-assisted method and multiwalled carbon nanotubes (CNTs). Remarkably, it took only about 1.5 min to completely the preparation process including the pyrolysis of ferrocene (iron sources) and the formation of Fe/Fe 3 C nanoparticles uniformly distributed on the CNTs. Due to the unique heterostructure, enhanced electrical conductivity and adequate dispersion of active sites, the fabricated sensors exhibit favorable selectivity and great sensing property, yielding a distinguishable and selective response to DA down to 15 nM with a good linearity scope of 0.050–40 μM. The developed Fe/Fe 3 C@CNT electrode was then successfully applied to monitor the DA level from the real samples, which holds considerable promise for electrochemical detection and biosensing applications. • The Fe/Fe 3 C nanoparticles uniformly attached on the CNTs by a fast microwave-assisted method. • The particular heterostructure can provide rich active sites and achieve efficient catalytic performance. • The Fe/Fe 3 C@CNT/GCE exhibits great electrochemical sensing toward dopamine because of effective exposure of active sites. • The novel electrochemical sensor has the potential to detect dopamine in real biological serum samples. [ABSTRACT FROM AUTHOR]

NiMoO4·H2O nanoclusters with one-dimensional nanorods have been synthesized via a facile and rapid microwave assisted method. The formation mechanism of the NiMoO4·H2O is confirmed as speedy self-assembly process via controlling the reaction time using FTIR technology. The as-prepared NiMoO4·H2O nanoclusters have a uniform size of 3μm and are composed of NiMoO4·H2O nanorods of about length of 1μm and diameter of 100nm, which shows a specific capacitance of 680Fg−1 at a current density of 1Ag−1, and good reversibility with a cycling efficiency of 98% after 1000 cycles. The excellent electrochemical performance makes the microwave assisted synthesis of NiMoO4·H2O nanoclusters a promising electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

Abstract: To improve the photodegradation efficiency for ciprofloxacin (CIP), a new-type microwave-assisted in situ growth method is developed for the preparation of reduced graphene oxide (RGO) -BiVO4 composite photocatalysts. The as-produced RGO-BiVO4 composite photocatalysts show extremely high enhancement of CIP degradation ratio over the pure BiVO4 photocatalyst under visible light. Specially, the 2wt% RGO-BiVO4 composite photocatalyst exhibits the highest CIP degradation ratio (68.2%) in 60min, which is over 3 times than that (22.7%) of the pure BiVO4 particles. The enhancement of photocatalytic activities of RGO-BiVO4 photocatalysts can be attributed to the effective separation of electron–hole pairs rather than the improvement of light absorption. [Copyright &y& Elsevier]

Abstract: Single phase perovskite LaFeO3 nanoparticles are directly synthesized by a one-step microwave-assisted route without additional high temperature calcination process. The prepared sample is characterized by X-ray diffraction (XRD), field emission scanning microscope (FE-SEM), Brunauer–Emmett–Teller (BET) specific surface area measurement, diffuse reflectance spectroscopy (DRS) and Fourier transform infrared spectroscopy (FTIR). XRD and SEM show that the prepared LaFeO3 is single phase perovskite and sphere-like shape. The DRS result shows that the prepared LaFeO3 has strong visible-light absorption and an optical absorption onset of 525 nm, corresponding to an optical band gap of 2.36 eV. The photocatalytic experiment demonstrates that LaFeO3 is highly visible-light photocatalytic active for the degradation of methylene blue. It is suggested that the narrow band gap and the strong visible-light absorption are responsible for the high visible-light photocatalytic activity of the prepared LaFeO3. [Copyright &y& Elsevier]

Abstract: The aim of this work was to perform a systematic study of the parameters that can influence the composition, morphology, and catalytic activity of PtSn/C nanoparticles and compare two different methods of nanocatalyst preparation, namely microwave-assisted heating (MW) and thermal decomposition of polymeric precursors (DPP). An investigation of the effects of the reducing and stabilizing agents on the catalytic activity and morphology of Pt75Sn25/C catalysts prepared by microwave-assisted heating was undertaken for optimization purposes. The effect of short-chain alcohols such as ethanol, ethylene glycol, and propylene glycol as reducing agents was evaluated, and the use of sodium acetate and citric acid as stabilizing agents for the MW procedure was examined. Catalysts obtained from propylene glycol displayed higher catalytic activity compared with catalysts prepared in ethylene glycol. Introduction of sodium acetate enhanced the catalytic activity, but this beneficial effect was observed until a critical acetate concentration was reached. Optimization of the MW synthesis allowed for the preparation of highly dispersed catalysts with average sizes lying between 2.0 and 5.0 nm. Comparison of the best catalyst prepared by MW with a catalyst of similar composition prepared by the polymeric precursors method showed that the catalytic activity of the material can be improved when a proper condition for catalyst preparation is achieved. [Copyright &y& Elsevier]

Abstract: A new strategy is discussed for deposition of monodisperse ZnO nanocrystals on the surface of reduced graphene oxide (rGO) sheets to form rGO/ZnO nanohybrids via a microwave-assisted route in a non-aqueous media. This is a facile and rapid process, which only requires a proration of zinc salt and rGO sheets react in diethylene glycol (DEG) under a low level of microwave irradiation (300W) for 10min. The as-prepared nanohybrids demonstrate well-dispersed ZnO nanocrystals loading and powerful photocatalytic activity for the decolorization of self-photosensitized dyes (rhodamine-B and methylene blue) under visible-light illumination. Here, DEG does not only help to enhance dispersion of rGO sheets, but also play an important role of controlling the growth of ZnO. Furthermore, the average size and loading amount of ZnO nanocrystals can be conveniently varied or controlled by the concentration of zinc precursor. The result uncovers that the loading of ZnO nanocrystals in the as-prepared nanohybrids is crucial to obtain an optimal synergistic effect between ZnO and rGO sheets in the mediated photocatalysis process for the photosensitized dyes decolorization. Accordingly, the optimum matching for the best photocatalytic activity is investigated thoroughly and a reasonable mechanism is also proposed. [Copyright &y& Elsevier]

Abstract: Single crystal tungsten oxide (WO3) nanoparticles were prepared via a microwave-assisted method. Electrochemical activity for hydrogen evolution reaction (HER) on WO3 supported on carbon black (WO3/C) electrocatalyst was first studied in acid solution (0.5 M H2SO4) and alkaline solution (1.0 M KOH) at room temperature. The overall experimental results revealed that the electrocatalytic activity for HER on WO3/C is one order magnitude higher than those obtained with carbon black in 0.5 M H2SO4 and is six times than in the case of carbon black in 1.0 M KOH. These results demonstrated that WO3 could enhance the electrocatalytic activity for hydrogen evolution reaction in acid solution (0.5 M H2SO4) and alkaline solution (1.0 M KOH). On the other hand, the kinetic reaction mechanisms were discussed on WO3/C electrocatalysts and carbon black in acid solution and alkaline solution for HER. Consequently, the rate-determining step changed from Tafel to Volmer due to the incorporation of WO3 in acid solution. However, the rate-determining step carries through Tafel reaction on both electrocatalysts in alkaline solution though WO3 was introduced. [Copyright &y& Elsevier]

Abstract: Water-soluble CdTe nanoparticles were synthesized in aqueous solution with the assistance of mercaptoacetic acid (MAA) molecules by wet chemical route and microwave-assisted method. A series of cadmium telluride (CdTe) nanoparticles capped with a bifunctional molecule, which contains both thiols and carboxylic acid groups were prepared using different pH values and using potassium tellurite as tellurium source. Thiol-capped nanocrystals of CdTe can be isolated as powders using 2-propanol. The synthesized thiol-capped CdTe were characterized with EDAX, TEM, Raman, FT–IR, UV–Visible absorption, fluorescence spectroscopy and X-ray diffraction (XRD) for the particle size determination and to understand their optical properties. The particles crystallize predominantly in cubic phase with narrow photoluminescence emission. Potassium tellurite as source of tellurium improves the photoluminescence efficiency and also avoids the cumbersome processes associated with H2Te or NaHTe sources. [Copyright &y& Elsevier]

Abstract: Some 2-amino-4,6-diarylpyrimidines 2 have been prepared from substituted benzylideneacetophenones and guanidine hydrochloride in the presence of alkali by conventional heating in alcoholic medium and microwave heating in solvent-free conditions. N-(2,3,4,6-Tetra-O-acetyl-β-d-glucopyranosyl)-N′-(4′,6′-diarylpyrimidin-2′-yl)thioureas 4 have been synthesized by reaction of per-O-acetylated glucopyranosyl isothiocyanate 1 and substituted 2-amino-4,6-diarylpyrimidines 2. Two different methods have been used, namely, refluxing in anhydrous dioxane and solvent-free microwave-assisted coupling. The second procedure afforded higher yields in much shorter reaction times. The compounds 2 and 4 were tested for their antibacterial and antifungal activities in vitro against Staphylococcus epidermidis, Enterobacter aerogenes and Candida albicans by disc diffusion method. [Copyright &y& Elsevier]

• Cs 3 Bi 2 Br 9 perovskite nanocrystals in nonpolar solvents were synthesized by microwave-assisted approach. • Cs 3 Bi 2 Br 9 nanocrystals exhibit a high PLQY of 35.8%. • A blue LED was fabricated by using the Cs 3 Bi 2 Br 9 nanocrystals as color conversion materials. Lead halide perovskite nanocrystals (NCs) have attracted much attention due to their remarkable performances in optoelectronic applications, but their development is greatly limited by the lead toxicity and instability in environmental conditions. In this paper, we reported a simple microwave-assisted (MW-AT) method for the synthesis of non-toxic and stable all-inorganic Cs 3 Bi 2 Br 9 perovskite NCs in nonpolar solvent. The as-prepared NCs show a highly efficient blue emission at 434 nm and 460 nm. The photoluminescence quantum yield (PLQY) of Cs 3 Bi 2 Br 9 NCs is raised from 8.47% to 35.8% because of effective passivation of surface trap-states by BiOBr. In addition, a blue light-emitting diode (LED) are fabricated by coating Cs 3 Bi 2 Br 9 NCs/silica composite onto a 365 nm GaN LED chip. This work provides a new synthetic path for preparing lead-free perovskite NCs, and demonstrates their promising application in solid-state lighting. [ABSTRACT FROM AUTHOR]

Abstract: The preparation of triazo dye direct blue 71 (DB71)-encapsulated mesostructured MCM-41 materials has successfully been performed by a microwave-assisted method or under conventional room temperature condition. The structures and properties were characterized by XRD, N2 adsorption analysis, electron microscopy, FT-IR, 13C NMR, UV–vis, and TGA–DSC. A blue-shift of UV–vis spectra was observed in the conventional room temperature-synthesized DB71/MCM-41 sample, and a red-shift in the microwave-synthesized DB71/MCM-41 samples, which may give a wide optical application. [Copyright &y& Elsevier]

Microalbuminuria (MAU) is an important biomarker for the diagnosis of kidney disease. Conventional methods for diagnosing MAU are often inaccurate and costly. In the present work, MAU has been identified as a biomarker for the diagnosis of kidney disease using a magnetic nanobiosensor. The normal range and standard curve of the magnetic nanobiosensor are obtained through interaction of Fe 3 O 4 nanorods synthesized by microwave-assisted method and albumin. The aim of this study is to fabricate a magnetic nanobiosensor with high accuracy and accuracy and precision in detecting MAU. So, the novelty of the magnetic nanobiosensors over other commonly used laboratory methods is known to be their ability to faster help patients. The results show that the magnetic nanobiosensor can be a good option for detecting MAU due to its high accuracy (R2 = 0.9251) in the normal range of 0.4 mg/mL to 6.4 mg/mL. [ABSTRACT FROM AUTHOR]

[Display omitted] • Magnesium incorporated hydroxyapatite was synthesized by using microwave-assisted wet chemical method. • The spectrophotometer method was used to perform the hemolytic activity of the samples. • The chemical bonding of the samples was confirmed by the FTIR spectrum. • The HR-TEM confirms the spherical morphology of the synthesized samples. • The in vitro antibacterial activity of the samples was studied. • The in vitro anti-inflammatory activity against standard drug diclofenac sodium for the samples were studied. • The samples were non-hemolytic according to the ASTM F756-00 (American Society for Testing and Materials Designation). In this work, we have investigated the antibacterial and hemolytic efficacy of hydroxyapatite (HA) and Magnesium (Mg) incorporated hydroxyapatite (MHA), where the composite was synthesized by a rapid and cost-effective microwave-assisted wet chemical method. The synthesized MHA composite was characterized by using X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), High-resolution transmission electron microscopy (HRTEM), in vitro antibacterial and anti-inflammatory activities. Also, the hemolytic activity of the sample was studied using the spectrophotometer technique. From the analysis, the XRD diffractogram confirms the presence of HA and MHA by the JCPDS card no: 09-0432. The chemical bonding confirmed the presence of Mg and HA in the nanocomposite and the HRTEM confirmed the spherical shape morphology of synthesized samples. The in vitro antibacterial activity of the nanocomposite was studied against the gram-positive bacteria Staphylococcus aureus and gram-negative bacteria Escherichia coli. Also, the in vitro anti-inflammatory activity of the sample was studied against the standard drug Diclofenac sodium and found to be compatible with the standard values. Further, the samples are investigated to be non-hemolytic according to the ASTM F756-00 (American Society for Testing and Materials Designation). Based on the studies, the prepared Mg-HA nanocomposite can be potential for the biomedical applications of dental, orthopaedic, and stem cell research. [ABSTRACT FROM AUTHOR]

The TiO 2 /NRGO composite contributes to excellent cycling performance. [Display omitted] • Anatase/rutile TiO 2 /NRGO composite was prepared by microwave-assisted method. • The NRGO support causes a superior electrochemical performance for sodium storage. • The crystal interface effect of mixed-phase TiO 2 could improve the dispersion rate of ions/Na+. • The sample retains a capacity of 223.3 mA h g−1 after 50 cycles at 0.1 A g−1. To solve the problems of TiO 2 electrode materials, such as short cycle life and intrinsic poor conductivity, N-doped modified graphene/mixed crystal phases TiO 2 composites (TiO 2 /NRGO) have been prepared by microwave-assisted method. The numerous spherical hybrid anatase/rutile TiO 2 nanoparticles evenly anchored on NRGO nanosheets and the TiO 2 nanoparticles are approximately 20−50 nm. The ions/Na+ diffusion rate can be increased by the crystal interface effect of mixed crystal phases TiO 2. In addition, the doping of nitrogen further improves the sodium storage properties of the composites. With this strategy, the as-prepared TiO 2 /NRGO composites deliver remarkable reversible capacities (223.3 mA h g−1 at 0.1 A g-1 over 50 cycles) and outstanding rate capability (101.1 mA h g−1 at 2 A g−1) for Na-ion batteries (NIBs). [ABSTRACT FROM AUTHOR]

• Synthesis of different TiO 2 -based nanostructures and improving their photocatalytic performances. • A comparison reported on the photocatalytic activity of differently prepared perovskite nanostructures. • A full structural, optical, and morphological analysis were reported. • Utilizing bandgap engineering strategy for obtaining the best performance for removing MB from water. This study was conducted to improve the photocatalytic performance of TiO 2 in the visible light range using TiO 2 based nanostructures. For this purpose, TiO 2 nanostructures were prepared by using the microwave-assisted technique and then used to prepare barium titanate (BaTiO 3), bismuth titanate (Bi 4 Ti 3 O 12), and zinc titanate (ZnTiO 3) nanostructures. The thermal, structural, purity, surface morphology, and optical studies were conducted through the TGA/DTA, XRD, EDX, FE-SEM, and UV–vis analyses. The crystallite sizes of TiO 2 , bismuth titanate, barium titanate, and zinc titanate nanostructures were obtained 45, 32, 32, and 29 nm respectively. The optical band gap of prepared samples was evaluated at 3.65, 2.65, 2.80, and 3.80 eV, respectively. The photocatalytic activity of the perovskite nanostructures on methylene blue degradation was evaluated and the results showed that bismuth titanate nanostructures with smaller bandgap have higher photocatalytic activity among prepared samples in the visible light range. [ABSTRACT FROM AUTHOR]

• C-doped CuO/g-C 3 N 4 was prepared via facile, one-pot method using low-cost precursors. • Photocathodes were directly deposited on FTO substrate under microwave irradiation. • The amount of urea determined the microstructure of CuO and its optical properties. • Superiority of our synthesis method over many other solution-based ones is explored. • Mechanisms for heterojunction formation and PEC performance improvement are proposed. Cupric oxide (CuO) is a semiconductor of choice for photocathode in photoelectrochemical (PEC) applications due to its great sunlight absorption capability. However, photocorrosion is the main drawback of CuO. Herein, CuO/graphitic carbon nitride (g-C 3 N 4) with a unique microstructure, enhanced PEC performance, and considerable photostability is synthesized under microwave irradiation. A facile, one-pot method is utilized to directly deposit the nanocomposite onto fluorine-doped tin oxide from a solution containing copper precursor and urea. Possible mechanism of CuO/g-C 3 N 4 formation through this novel method is investigated. It is elucidated that controlled amounts of urea critically determine the morphological evolution of CuO, while its excess quantities convert to g-C 3 N 4 in the presence of CuO as the catalyst. Through an appropriate heat treatment, carbon is doped into CuO lattice. The obtained C-doped CuO/g-C 3 N 4 demonstrates 227% enhancement over CuO in photocurrent density and ~80% photocurrent retention. The enhanced photoelectrocatalytic activity is mainly attributed to unique morphology of CuO, effective separation of charge carriers, and formation of heterojunction. These characteristics manifest the superiority of this approach over many other chemical-based methods. The nanocomposite synergistically integrates the advantages of both the constituents, offering a low-cost, efficient photocathode for PEC water splitting, photocatalytic hydrogen evolution, and degradation of pollutants. [ABSTRACT FROM AUTHOR]