Synthesis of Cu2O-amine-functionalized graphite nanosheet (AFGNS) composite has been accomplished at room temperature. In the first step, AFGNS is synthesized by wet chemical functionalization where the -NH2 groups formed on nanosheet surface help to anchor the Cu(2+) ions homogeneously through coordinate bonds. Reduction of Cu(2+) (3.4 × 10(-2) mmol) in the presence of NaBH4 (1.8 mmol) can be restricted to Cu(1+) on AFGNS surface at room temperature. This leads to the formation of uniform Cu2O nanoparticles (NP) on AFGNS. The role played by the -NH2 groups in anchoring Cu(2+) ions and followed by stabilizing the Cu2O NP on AFGNS was understood by controlled reactions in the absence of -NH2 groups and without any graphitic support, respectively. The prepared Cu2O-AFGNS composite shows excellent catalytic activity toward degradation of an azo dye, methyl orange, which is an environmental pollutant. The dye degradation proceeds with high rate constant value, and the composite shows high stability and excellent reuse capability.

A facile route to synthesize amine (-NH 2 ) functionalized graphite nanosheets (AFGNS) by 2-step controlled chemical modification of microcrystalline graphite is described. The method begins with nitration by mixed acid (HNO 3 : H 2 SO 4 in 1 : 1 v/v ratio), followed by reduction with Na 2 S to form AFGNS. The AFGNS was reacted with carboxylic acid-terminated polyethylene glycol (PEG) chains (MeO-mPEG-COOH, M W = 5000 Da) in the presence of a carbodiimide coupling agent to obtain a water-soluble PEGylated AFGNS (P-AFGNS) composite.Anticancer drug doxorubicin (DOX) was loaded on this composite with a loading capacity of 0.296 mg mg À1for an initial concentration of 0.232 mg mL À1 DOX and 0.136 mg mL À1 of P-AFGNS and the release of DOX from this water-soluble DOX loaded P-AFGNS composite at two different temperatures was found to be strongly pH dependent.

Development of aluminum nitride (AlN)-single walled carbon nanotube (SWCNT) ceramic-matrix composite containing 1-6 vol% SWCNT by hot pressing has been reported in this article. The composites containing 6 vol% SWCNT are dense (~99% relative density) and show high dc electrical conductivity (200 Sm À1 ) and thermal conductivity (62 Wm À1 K À1 ) at room temperature. SWCNTs contain mostly metallic variety tubes obtained by controlled processing of the pristine tubes before incorporation into the ceramic matrix. Raman spectroscopy and field emission scanning electron microscopy (FESEM) of the fracture surface of the samples show the excellent survivability of the SWCNTs even after high-temperature hot pressing. The results indicate the possibility of preparation of AlN nanocomposite for use in plasma devices and electromagnetic shielding. K E Y W O R D S aluminum nitride, electrical conductivity, nanocomposites, single walled carbon nanotubes, thermal conductivity

The synthesis of a mesoporous γ‐Al2O3 nanorod/reduced graphene oxide (γ‐Al2O3NR/RGO) composite with a higher surface area and thermal conductivity than unmodified γ‐Al2O3 has been accomplished, and these materials were characterized in detail. The composite was used successfully as a support for poly(ethylenimine) (PEI) to capture CO2 at high temperature. The PEI‐modified composite (γ‐Al2O3NR/RGO/PEI) showed an excellent CO2 adsorption from simulated flue gas at 75 °C and complete desorption at 100 °C with recyclability. The maximum CO2 adsorption capacity of this material was 200.6 mg gPEI−1 (1.14 mmol CO2 gadsorbent−1) with an amine efficiency of 0.22, which is higher than that of bare γ‐Al2O3/PEI. As a result of its high thermal conductivity, the overheating of the adsorbent during exothermic CO2 adsorption by PEI was restricted and as a result the thermal degradation of PEI was prevented. Accordingly, the adsorption capacity of γ‐Al2O3NR/RGO/PEI does not deteriorate like that of bare γ‐Al2O3/PEI during repeated CO2 adsorption–desorption cycles.

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Room temperature synthesis of micelle-protected highly fluorescent carbon nanodots (CNDs) and fabrication of scratch-resistant CND–ORMOSIL films and paint.

Discovery of plasmon resonance and negative permittivity in carbon allotropes at much lower frequencies than those of metals has evoked interest to develop random metacomposites by suitable means of addition of these dispersoids in an overall dielectric matrix. Random metacomposites have always the advantage for their easy preparation techniques over those of their regular arrayed artificial counterpart. However, thermal management during the heat generation by electromagnetic attenuation in metamaterials is not yet studied well. The present communication discusses the dielectric permittivities and loss parameters of aluminum nitride−single-wall carbon nanotube (AlN−SWCNT) composites considering high thermal conductivities of both materials. The composites are dense and have been prepared by a standard powder technological method using hot pressing at 1850 °C under a nitrogen atmosphere. Increase in the negative permittivity value with SWCNT concentration (1, 3, and 6 vol %) in the composites had been observed at low frequencies. Characterization of the materials with Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and microstructure analysis by scanning and transmission electron microscopy (TEM) revealed the survivability of the SWCNTs and the nature of the matrix−filler interface. Plasmonic resonance following Drude's law could be observed at much lower plasma frequencies than that of pure SWCNT and for very little SWCNT addition. Exhibition of the negative permittivity has been explained with relation to the microstructure of the composites observed from field emission scanning electron micrographs (FESEM), TEM images, and the equivalent circuit model. High energy conversion efficiency is expected in these composites due to the possession of dual functionalities like high thermal conductivity as well as high negative permittivity, which should ensure the application of these materials in wave filter, cloaking device, supercapacitors, and wireless communication.