Sonochemically Assembled Photoluminescent Copper-Modified Graphene Oxide Microspheres

Abstract

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.

Sonochemical Formation of Copper/Iron‐Modified Graphene Oxide Nanocomposites for Ketorolac Delivery

“…On the other hand, there is a FeS phase, which is a very stable crystalline phase, even at 800 °C and under pressures of up to several GPa. We assume that FeS may be formed according to a mechanism similar to that of copper sulfide, in agreement with our recent work . In this way, the difference in composition between copper‐ and iron‐modified@GO nanocomposites may be attributed to the characteristic electrochemical potentials of Cu (0.153 J mol −1 ) and Fe (−0.037 J mol −1 ); thus implying that more energy may be required for the reduction of Fe 3+ .…”

“…We assume that FeSm ay be formed accordingt oa mechanisms imilar to that of copper sulfide, in agreementw ith ourrecentwork. [55] In this way, thedifferenceincomposition betweenc opper-a nd iron-modified@GO nanocomposites mayb e attributed to thec haracteristice lectrochemicalp otentialso fC u (0.153 Jmol À1 )a nd Fe (À0.037Jmol À1 ); thus implying that more energy mayberequiredfor thereduction of Fe 3 + . Figure 3a and bs hows the surface chemical composition and bondingo fa s-synthesized GO (N1) and the sonochemically prepared nanocomposites (N2, N7, andN 9).…”

“…Appropriate GO purification and modification can increase the efficacy of drug loading in GO and optimizea dsorption/desorptionk inetics with minimal toxicity. [41][42][43][44] The rich GO surface chemistry facilitatesf unctionalization with diverse molecular compounds, such as dyes, [45] inorganic [45][46][47][48] and organic (DNA, [49] single-stranded RNA, [50] gene [51] )s ubstances, polymers, [52][53][54][55] and luminescento rf luorescent particles; [56,57] thus enablingas ynergistic effect of drug delivery and bioimaging [58][59][60][61] of ac arrierp latform. Immobilization with drug molecules can regulate GO dispersal in watero ri nt he cell culture media, reduce cell/tissue toxicity,a nd induce accumulationi n targetc ells andt issues.…”

Poly(Vinyl Alcohol) Enhances Acetylation of Ascorbic Acid in Superparamagnetic Graphene Oxide Nanoparticles Ultrasonically Complexed with Acetylsalicylic Acid

“…The size distribution and ξ-potential of colloids were measured by DLS from Malvern Instruments, Ltd., by using a Zetasizer Nano instrument and a prepared buffer solution. 35 DLS and ξ-potential (electrical charge) experiments were carried out on a 50 times diluted colloidal suspension. Each measurement took 10 s; the nanoparticle distribution and electrophoretic curves were obtained by averaging ten measurements.…”

Effect of ultrasound on nonsteroidal anti-inflammatory drugs complexed with copper, iron, zinc and graphene oxides

“…Для достижения поставленной цели работы синтезировали наночастицы: графен, Cu/Fe-графен, ZnO-графен и Fe3O4 с помощью ультразвука (20 кГц) в водной фазе. Для синтеза оксидированного графена использовали графит (9,3-47,2 мкм, элементный состав: C (94,96 ± 2,00 at.%), O (4,03 ± 0,80 at.%), Ti (0,11 ± 0,01 at.%), Ca (1,07 ± 0,10 at.%), Mn (0,02 ± 0,01 at.%)) по методу [11], применяя ультразвуковой диспергатор N.4-20 (Cavitation Inc.), предварительно выполнив калибровку прибора. Нанокомпозиты Cu/Fe-графена и Fe3O4 были сформированы в результате разработки методов сонохимического синтеза [8,9].…”