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A fast, simple, and energy-saving microwave-assisted approach was successfully developed to prepare carbon microspheres. The carbon microspheres with a uniform particle size and good dispersity were prepared using glucose as the raw material and HCl as the dehydrating agent at low temperature (90°C) in an open system with the assistance of microwave heating. The carbon microspheres were characterized by elemental analysis, XRD, SEM, FTIR, TG, and Raman. The results showed that the carbon microspheres prepared under the condition of 18.5% (v/v) HCl and heating for 30 min by microwave had a narrow size distribution. The core–shell structure of the carbon core and TiO2 shell was prepared with (NH4)2TiF6, H3BO3 using the microwave-assisted method. The hollow TiO2 microspheres with good crystallinity and high photocatalytic properties were successfully prepared by sacrificing the carbon microspheres.

Microwave synthesized activated carbon utilizing Tridax procumbens flowers is reported as supercapacitor electrode. Incomplete graphitization with disordered carbon structure and honeycomb-like surface morphology is achieved. In aqueous H2SO4 electrolyte, the material exhibits charge storage through non-faradaic, electrostatic accumulation/adsorption of charges at electrode-electrolyte interface. The charge/discharge curves confirm the capacitive behavior of the material with a specific capacitance of 168 F g−1 at a current density of 0.5 A g−1. A notable energy density of 2.46 W h kg−1 at a 163 W kg−1 power density is achieved in the assembled symmetric device making it a pertinent electrode material for supercapacitors.

Nanocomposites comprising nitrogen-doped TiO2 and reduced graphene oxide (N/TiO2/rGO), with different rGO loading qualities, were prepared by a cost-effective microwave-assisted synthesis method. The synthesized materials were broadly characterized by Raman spectroscopy, X-ray diffraction (XRD), infrared spectroscopy (FTIR), photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), electron microscopy (SEM-EDS), and nitrogen adsorption/desorption isotherms. Anatase was the only crystalline phase observed for all synthesized materials. The rGO loading did not affect the morphological properties, but it positively influenced the photocatalytic activity of the nanocomposite materials, especially at low rGO loading. Photocatalysts were evaluated via the degradation of specific organic micropollutant (OMP) pharmaceuticals: ciprofloxacin (CIP), diclofenac (DCF), and salicylic acid (SA), under different radiation sources: ultraviolet A (UVA), solar light simulator (SLS), blue visible light (BVL) and cold visible light (CVL). CIP and SA were removed effectively via the synergy of adsorption and photocatalysis, while DCF degradation was achieved solely by photocatalysis. After implementing scavenger agents, photocatalytic degradation processes mainly depended on the specific pollutant type, while irradiation sources barely defined the photocatalytic mechanism. On the other hand, changes in irradiation intensity significantly influenced the photolysis process, while photocatalysis was slightly affected, indicating that irradiation spectra are more relevant than intensity.

A simple, low-cost and an eco-friendly synthesis of Ir-doped titanium dioxide nanoparticles (TiO2 NPs) with an anatase phase by the microwave-assisted method using an aqueous solution of titanium tetra-isopropoxide (TTIP) and iridium (III) chloride monohydrate. The synthesized Ir-doped TiO2 NPs were characterized by using various spectro-analytical techniques for the confirmation of NPs. The photocatalytic activity of the synthesized Ir-doped TiO2 NPs has been evaluated by taking 2-chlorophenol (2-CP), 4-chlorophenol (4-CP), 2,4-dichlorophenol (2,4-DCP) and 2,4,6-trichlorophenols (2,4,6-TCP) as model water contaminant pollutants under sunlight irradiation. The photocatalytic conversion is approximately 84.24%, 81.22%, 76.01% and 72.11% of 2-CP, 4-CP, 2,4-DCP and 2,4,6-TCP respectively, by using the synthesized Ir-doped TiO2 NPs. The efficient photocatalytic degradation was observed in the degradation of 2-CP in 60 min of sunlight irradiation. The rate equation of photocatalytic degradation mechanism was followed pseudo-first order kinetics. Finally, the screening of antimicrobial activity by paper disc method against few bacteria, such as Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), Bacillus subtilis (B. subtilis) and Staphylococcus aureus (S. aureus) and fungi such as Aspergillus niger (A. niger) and Candida albicans (C. albicans), showed that the prepared Ir-doped TiO2 NPs have the prominent results.

Hydroxyapatite is mainly used in biomedical applications because of its very important property—bioactivity. [...]

In this work, a facile one-step microwave-assisted method for deposition of monodisperse Ni nanospheres on reduced graphene oxide (rGO) sheets to form Ni-rGO nanohybrids is discussed. In the presence of hydrazine monohydrate, Ni nanospheres are grown onto rGO sheets using nickel precursor and GO as starting materials in ethylene glycol (EG) solution under a low level of microwave irradiation (300 W) for 20 min, during which GO is also reduced to rGO. The as-prepared nanohybrids exhibit well-dispersed Ni nanosphere (about 80 nm in diameter) loadings and effective reduction of graphene oxide. The resulting Ni-rGO nanohybrids-modified glassy carbon electrode (GCE) shows significantly improved electrochemical performance in nonenzymatic amperometric glucose detection. In addition, interference from the oxidation of common interfering species under physiological conditions, such as ascorbic acid (AA) and uric acid (UA), is effectively avoided.

Environmental pollution caused by the improper disposal of pharmaceuticals is a matter of global concern, and warrants immediate attention. Of particular concern is the aquatic contamination caused by the increasing use of antibiotics, which could give rise to superbugs. While researchers have mainly focused on improving the adsorption capacity of mostly activated carbon-based adsorbents, we have developed a non-conventional adsorbent (SiC nanoparticles) in the present work for the adsorptive removal of four different nitroimidazole antibiotics, namely metronidazole (MNZ), dimetridazole (DMZ), ronidazole (RNZ), and tinidazole (TNZ). In addition to the unique properties which are inherent to SiC, the present adsorbent not only possesses a high adsorption capacity, but also shows one of the highest adsorption rates; both of which are prerequisites for an efficient and cost-effective adsorption-based separation technology. Silicon carbide (SiC) nanoparticles, synthesized by a microwave-assisted method, were thoroughly characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and the Brunauer–Emmett–Teller method. The adsorption isotherm data were accurately described by the Langmuir isotherm model. On the other hand, the adsorption kinetics, closely represented by the pseudo-second order kinetic model, were faster than most previously reported adsorbents. The reaction rate constants were 0.0089, 0.0079, 0.0072, and 0.0055 g/(mg min), for MNZ, DMZ, RNZ, and TNZ, respectively.