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Gemini surfactants are presently gaining attention due to their unusual self-assembling characteristics and incomparable interfacial activity. Current research work involves the cost-effective microwave (MW) synthesis of waste soybean oil-based gemini imidazolinium surfactants (GIS) having a carbonate linkage in its spacer moiety. Structural characterizations of the materials have been done using FT-IR, ¹H-NMR and ${}^{13}$C-NMR. Using indigenous and natural material as base and MW as energy source for synthesizing the GIS with easily degradable chemical moiety make them to be labeled as green surfactants.

Microwave synthesis of imidazolines has been proven to have various advantages over conventional thermal methods in terms of reaction duration, better yield and sustainability. Multi-exploitability of imidazolines at industrial level is globally known. Moreover, claims of multi-fold improvement of the properties of gemini surfactants over their conventional monomeric counterparts challenge the researchers to synthesize gemini imidazoline surfactants using green synthetic routes. Cost-effective products provide an additional demand to commercialize the product easily. This research involves the microwave synthesis of gemini imidazolines using easily available, low-cost reactants. Synthesized products were characterized using standard characterization procedures and were evaluated for their surface-active properties and applications.

This research focuses on understanding the nature of the Fe ions substituted in hydroxyapatite ((HAP) Ca_10-xFe_x(PO₄)₆(OH)_2-xÿ_x: x = 0, 0.2 and 0.4) powder synthesized at temperatures between 500°C and 1000°C and their crystallization. The DSC scan indicates a solid state phase transition at about 757°C for the as-prepared powder HAP. The transformation of HAP to β-tricalcium phosphate (β-TCP, β-Ca₃(PO₄)₂) is seen when the powder were heated to 750°C. The sizes of the crystallites were determined to be about 46–51 nm, 33–40 nm and 33–59 nm for Fe content of 0, 0.2 and 0.4 mol%, respectively. The ESR parameters for the Fe³⁺ ions, g = 4.23 and 8.93 indicated that the ions were subjected to a rhombic ion crystal field within the HAP structures. The g values of ~2.01 indicated that the particles were super-paramagnetic and ferromagnetic iron nanoparticles, having an average size about 0.2–0.5 μm in length.

Lead(II) phthalocyanine (PbPc); lead(II) tetranitrophthalocyanine (PbTNP) and lead(II) tetraaminophthalocyanine (PbTAP) were synthesized in pure state by microwave irradiation and conventional heating methods. The procedures for their synthesis by the microwave technique are standardized and reported for the first time. PbPc and PbTNP were synthesized in dry conditions and PbTAP complex was synthesized in aqueous medium. All the compounds are obtained in very high yield (~90%). The synthesized complexes are characterized with respect to elemental analysis, UV-visible, IR-spectroscopy and X-ray diffraction study. The microwave methods are advantageous over the conventional method of synthesis with respect to higher yield, rapidity and simplicity.

The synthesis of various axially substituted titanium phthalocyanines in high yield using microwave irradiation without an added solvent is reported. The times of reaction, as expected, are short and generally less than 10 minutes. The products were obtained in high purity after chromatography.

The effective 'one-pot' microwave-assisted synthesis of several substituted 5,10,15,20-tetraarylporphyrins is reported. The microwave-assisted insertion of five different transition metals into the 5,10,15,20-tetraphenylporphyrin, 5,10,15,20-tetrakis(4-chlorophenyl)porphyrin and 5,10,15,20-tetrakis(3-hydroxyphenyl)porphyrin core was also achieved with high yields. In addition to their simplicity, both these straightforward, experimental protocols were also characterized by extremely short reaction times and quite small quantities of solvents employed.

The present work was addressed to study the visible light induced performance as photocatalysts of mesoporous N_yTi_1–xCe_xO_2–y structures obtained under microwave irradiation. The titanium dioxide (TiO₂) was doped with cerium and nitrogen in order to improve the quantum efficiency of the TiO₂ and to shift its adsorption spectra to the visible region. The prepared meso-powders were analyzed by means of X-ray diffraction (XRD), scanning Electron microscopy (SEM), infrared (IR) spectroscopy, transmission electronic microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The surface area was evaluated by means of the Brunauer-Emmett-Teller (BET) method and ultraviolet (UV)-visible diffuse reflectance measurements were performed in order to determine the band gap energy. In addition, the photocatalytic activity of the samples was evaluated by monitoring the photodegradation of methylene blue (MB) under UV and visible light energy irradiation. The results show that our methodology is an effective way for incorporating cerium and nitrogen into TiO₂ compound, which in turn, increases its photocatalytic activity. The diffuse reflectance analysis confirms that the absorption edge was shifted towards the visible region of the optical spectrum. The XRD diffraction patterns indicate homogeneous solid solutions in which prevails the anatase phase. It was observed a reduction in crystal size from 13.1 nm to 7.7 nm for N_yTi_0.98Ce_0.02O_2–y in comparison to TiO₂. The textural properties of the synthesized compounds were determined, by means of adsorption isotherms indicating the formation of mesoporous structures. IR spectra show characteristic vibration signals attributed to Ti–O–Ti bonds, as well as vibrations assigned to cerium and nitrogen bonds. The XPS analyses evidence the presence of Ce³⁺/Ce⁴⁺ redox couple and Ti–N bonds. The photocatalityc efficiency was evaluated in the degradation of MB monitoring the absorbance change at 664 nm. The degradation of this compound was 91.4% using N_yTi_0.98Ce_0.02O_2–y as photocatalyst under UV energy in 90 min. Also 38.7% of MB degradation was achieved in 150 min under visible light radiation.

Nano-hydroxyapatite (nHAp)-based dual-/multi-modal bioimaging systems have received significant attention due to their excellent bioactivity and biocompatibility. However, it is difficult to obtain highly sensitive imaging results. On the one side, the high surface energy of nHAp tends to enable the agglomerations of nHAp, which could further limit the clinical applications. On the other side, the main strategy for the construction of co-doped nHAp nanocrystals depends on high temperature and techniques of post-modification, resulting in inevitable nHAp crystal polymerization and increased particle size. In order to overcome the current shortcomings of nonmonodispersed nHAp, such as uneven distribution and easy aggregation, the construction of monodispersed nHAp is expected to ensure the imaging performance of traceable nHAp by reducing the aggregation of nHAp in vivo and improving the imaging sensitivity. Thus, in this review, the approaches of monodispersed nHAp based on hydrothermal, biomimetic and microwave synthesis methods are summarized. Furthermore, the development of single/multi-mode traceable monodispersed nHAp for biological imaging applications is also discussed.

ZnO nanorods assembled in flower shaped morphology have been successfully synthesized using low power microwave irradiation in a very short duration. The diameter and length of the rods were within 150–190 nm (tip diameter ~15 nm) and 2 μm, respectively, with an aspect ratio of 20–22. The synthesized nanorods were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), high resolution transmission electron microscopy (HRTEM), Fourier transform infrared microscopy (FT-IR), photoluminescence (PL) and magnetization measurements. The XRD and FT-IR results indicate that ZnO nanorods have the pure wurtzite structure with lattice parameters a and c of 3.254 and 5.197 Å, respectively. The selected area electron diffraction (SAED) pattern reveals that the ZnO nanorods are single crystal in nature and grow along [001] plane. Room-temperature PL spectrum of the as-grown ZnO nanorods shows a near-band-edge (NBE) emission peak and defect induced emissions. Magnetization measurements indicate that ZnO nanorods exhibit room temperature ferromagnetism with remanent magnetization (Mr) and coercivity (H_c) about 2.92 × 10^-4 (emu/g) and 29.75 Oe, respectively, which may be due to the presence of defects in the ZnO nanorods.

Chalcopyrite CuGaSe₂ nanocrystals with average size about 90 nm were synthesized by quick and cheap microwave assisted polyol method without special dissolving of Se in organic solvents. Composition, structure and optical properties of the obtained particles correspond to pure bulk CuGaSe₂. CuGaSe₂/PCBM composite films produced from the synthesized nanoparticles possess reproducible photovoltaic response.

This manuscript describes a general and simple method to carbon-coat quantum dots (QDs) using microwave-assisted technology. By coating QDs with carbohydrates, you extend their application for bioimaging (in vitro and in vivo) as the metal core is now shielded by a protective coating layer. XRD and TEM verified that nanoparticles were coated with a layer of carbon-based material (reduced sucrose). In addition, we demonstrated the versatility of this approach by coating other types of nanoparticles (i.e. gold). UV–Visible spectroscopic analysis presented a red shift in absorbance after carbon coating which further confirmed that the surface of these nanoparticles was modified. QDs emission wavelength was not altered but experienced an increase in intensity. The carbon-coated QDs and gold nanoparticles generated in this study measured 14 nm and 60 nm, respectively.