Af easible sonochemicala pproach is described for the preparationo fc opper/iron-modified graphene oxide nanocomposites through ultrasonication (20 kHz, 18 Wcm À2 ) of an aqueous solutionc ontaining coppera nd iron ion precursors. Uniquec opper-, copper/iron-and iron-modified graphene oxide nanocomposites have as ubmicron size that is smaller than that of pristine GO and ah ighers urfacea rea enriched with Cu 2 O, CuO, and Fe 2 O 3 of multiform phases (a-, b-, e-, or g), FeO(OH), and sulfur-o rc arbon-containingc om-pounds. These nanocomposites are sonochemically intercalated with the nonsteroidal anti-inflammatory drug ketorolac, which results in the formationo fn anoscale carriers. Ketorolac monotonically disintegratesf rom these nanoscale carriers in aqueous solution upon adjustment of the pH from 1t o8 .T he disintegration of ketorolacp roceeds at a slowerr ate from the copper/iron-modified grapheneo xide at increased pH, but at af aster rate from the iron-modified graphene oxide undera cidic conditions.

A new accessible sonochemical assembly method is developed for the preparation of photoluminescent oil-filled silica@CuS/CuO/CuO-graphene oxide (GO) microspheres that emit light of green, yellow, and red colors. This method is based on the ultrasonic emulsification of a biphasic mixture consisting of CuS/CuO/CuO-graphene oxide (GO) nanocomposites with poly(vinyl alcohol) (PVA) (aqueous phase) and tetraethyl orthosilicate with sunflower oil (organic phase). CuS/CuO/CuO-GO nanocomposites are composed of sonochemically formed three phases of copper: covellite CuS (p-type semiconductor), cuprite CuO (Bloch p-type semiconductor), and CuO (charge-transfer insulator). The photoluminescence properties of microspheres result from H-bridging between PVA and CuS/CuO/CuO-GO nanostructures, light absorption ability of CuO, and charge-transfer insulation by CuO. Substitution of PVA by S-containing methylene blue quenches fluorescence by enhanced dye adsorption on CuS/CuO/CuO-GO because of CuS and induced charge transfer. Non-S-containing malachite green is in a nonionized form and tends to be in the oil phase, prohibiting the charge transfer on CuS/CuO/CuO-GO.

Simultaneous mass production of high quality vertically oriented graphene nanostructures and doping them by using an inductively coupled plasma chemical vapor deposition (ICP CVD) is a technological problem because little is understood about their growth mechanism over enlarged surfaces. We introduce a new method that combines the ICP CVD with roll-to-roll technology to enable the in-situ preparation of vertically oriented graphene by using propane as a precursor gas and nitrogen or silicon as dopants. This new technology enables preparation of vertically oriented graphene with distinct morphology and composition on a moving copper foil substrate at a lower cost. The technological parameters such as deposition time (1–30 min), gas partial pressure, composition of the gas mixture (propane, argon, nitrogen or silane), heating treatment (1–60 min) and temperature (350–500 °C) were varied to reveal the nanostructure growth, the evolution of its morphology and heteroatom’s intercalation by nitrogen or silicon. Unique nanostructures were examined by FE-SEM microscopy, Raman spectroscopy and energy dispersive X-Ray scattering techniques. The undoped and nitrogen- or silicon-doped nanostructures can be prepared with the full area coverage of the copper substrate on industrially manufactured surface defects. Longer deposition time (30 min, 450 °C) causes carbon amorphization and an increased fraction of sp3-hybridized carbon, leading to enlargement of vertically oriented carbonaceous nanostructures and growth of pillars.

We demonstrate a single-step ultrasonic in situ complexation of salicylic acid during the growth of Fe3O4-reduced graphene oxide nanoparticles (∼10 nm) to improve the antioxidant and antiproliferative effects of pristine drug molecules. These nanoparticles have a precisely defined electronic molecular structure with salicylic acid ligands specifically complexed to Fe­(III)/Fe­(II) sites, four orders of magnitude larger electric surface potential, and enzymatic activity modulated by ascorbic acid molecules. The diminishing efficiency of hydroxyl radicals by Fe3O4-rGO-SA nanoparticles is tenfold higher than that by pristine salicylic acid in the electro-Fenton process. The H+ production of these nanoparticles can be switched by the interaction with ascorbic acid ligands and cause the redox deactivation of iron or enhanced antioxidation, where rGO plays an important role in enhanced charge transfer catalysis. Fe3O4-rGO-SA nanoparticles are nontoxic to erythrocytes, i.e., human peripheral blood mononuclear cells, but surpassingly inhibit the growth of three cancer cell lines, HeLa, HepG2, and HT29, with respect to pristine salicylic acid molecules.

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