scholarly journals Magnetic Properties of Poly(trimethylene terephthalate‐ block ‐Poly(tetramethylene oxide) Copolymer Nanocomposites Reinforced by Graphene Oxide–Fe 3 O 4 Hybrid Nanoparticles

2019 ◽  
Vol 216 (23) ◽  
pp. 1900402
Author(s):  
Anna Szymczyk ◽  
Sandra Paszkiewicz ◽  
Janusz Typek ◽  
Zdenko Špitalský ◽  
Izabela Janowska ◽  
...  
2012 ◽  
Vol 97 (3) ◽  
pp. 38001 ◽  
Author(s):  
Ross McIntosh ◽  
Messai A. Mamo ◽  
Brice Jamieson ◽  
Saibal Roy ◽  
Somnath Bhattacharyya

2015 ◽  
Author(s):  
Murugan Veerapandian ◽  
Suresh Neethirajan

Hybridization of distinct materials into a single nanoplatform is relevant to advance material’s properties for functional application such as biosensor platform. We report the synthesis and characterization of nanosheets of graphene oxide decorated with hybrid nanoparticles of silver-ruthenium bipyridine complex (Ag@[Ru(bpy)3]2+) core and chitosan shell. Hybrid nanoparticles were first obtained through a sequential wet-chemical approach using in situ reduction, electrostatic and coordination reaction. Oxygenated functional groups of graphene oxide and abundant amine groups of chitosan layer on the surface of hybrid nanoparticles allowed the functionalization reaction. Changes in intrinsic optical, chemical and structural properties of graphene oxide due to hybrid nanoparticles were studied in depth using spectroscopic techniques and an electron microscope. Electrodes modified with nanosheets of graphene oxide-hybrid nanoparticles retain the biocompatibility and displayed an amplified redox property suitable for a broad range of sensing studies.


2019 ◽  
Vol 814 ◽  
pp. 96-101
Author(s):  
Kun Yan Wang

Poly (trimethylene terephthalate) (PTT)/functionalized graphene oxide (fGO) nanocomposites were prepared by melt compounding. The crystalline morphology and crystallization behavior of PTT/fGO with different amounts of fGO were investigated by differential scanning calorimetry (DSC) and polarizing optical microscope (POM). The results show that the crystallization peak shifts to higher temperature after adding fGO, indicating that fGO have a nucleating effect on PTT. The crystallization temperature of nanocomposites increases with increasing content of fGO. The XRD pattern of PTT/fGO nanocomposites almost no change that indicated the degree of crystallinity of the PTT matrix remained unaffected by the addition of fGO. The nanocomposite revealed integrated Maltese crossed spherulitic morphologies. When adding 1% fGO to the PTT, big-sized PTT spherulites occurred and small-sized PTT spherulites were formed around the big-sized PTT spherulites which indicated that the mechanism of nucleation is changed.


Molecules ◽  
2019 ◽  
Vol 24 (4) ◽  
pp. 688 ◽  
Author(s):  
Kornelia Lewandowska ◽  
Natalia Rosiak ◽  
Andrzej Bogucki ◽  
Judyta Cielecka-Piontek ◽  
Mikołaj Mizera ◽  
...  

Graphene oxide (GO) was modified by two modified porphyrins (THPP and TCPP) to form GO–porphyrin hybrids. Spectroscopic measurements demonstrated the formation of stable supramolecular aggregates when mixing two components in solution. The Fourier transform infrared (FTIR) and Raman scattering measurements confirm π-stacking between hydrophobic regions of GO nanoflakes and porphyrin molecules. On the number and the kind of paramagnetic centers generated in pristine GO samples, which originate from spin anomalies at the edges of aromatic domains within GO nanoflakes. More significant changes in electronic properties have been observed in hybrid materials. This is particularly evident in the drastic increase in the number of unpaired electrons for the THPP-GO sample and the decrease in the number of unpaired electrons for the TCPP-GO. The difference of paramagnetic properties of hybrid materials is a consequence of π-stacking between GO and porphyrin rings. An interesting interplay between modifiers and the surface of GO leads to a significant change in electronic structure and magnetic properties of the designed hybrid materials. Based on the selection of molecular counterpart we can affect the behavior of hybrids upon light irradiation in a different manner, which may be useful for the applications in photovoltaics, optoelectronics, and spintronics.


2014 ◽  
Vol 131 (11) ◽  
pp. n/a-n/a ◽  
Author(s):  
Chengxin Guo ◽  
Liangliang Ji ◽  
Yaowen Li ◽  
Xiaoming Yang ◽  
Yingfeng Tu

2017 ◽  
Vol 2017 ◽  
pp. 1-15 ◽  
Author(s):  
Arturo Adrián Rodríguez-Rodríguez ◽  
Sagrario Martínez-Montemayor ◽  
César Cutberto Leyva-Porras ◽  
Francisco Enrique Longoria-Rodríguez ◽  
Eduardo Martínez-Guerra ◽  
...  

CoFe2O4nanoparticles decorated and wrapped with TiO2nanoparticles have been prepared by mixing well-dispersed CoFe2O4with amorphous TiO2(impregnation approach) and growing amorphous TiO2over the magnetic core (seed approach), respectively, followed by thermal treatment to achieve TiO2crystallinity. Synthesis strategies were based on the oil-in-water microemulsion reaction method. Thermally treated nanomaterials were characterized in terms of structure, morphology, and composition, to confirm hybrid nanoparticles formation and relate with the synthesis approaches; textural, optical, and magnetic properties were evaluated. X-ray diffraction revealed coexistence of cubic spinel-type CoFe2O4and tetragonal anatase TiO2. Electron microscopy images depicted crystalline nanoparticles (sizes below 25 nm), with homogeneous Ti distribution for the hybrid nanoparticles synthesized by seed approach. EDX microanalysis and ICP-AES corroborated established chemical composition. XPS evidenced chemical states, as well as TiO2predominance over CoFe2O4surface. According to BET measurements, the hybrid nanoparticles were mesoporous. UV-Vis spectroscopy showed optical response along the UV-visible light region. Magnetic properties suggested the breaking order of magnetic domains due to modification with TiO2, especially for mediated seed approach sample. The properties of the obtained hybrid nanoparticles were different in comparison with its individual components. The results highlight the usefulness of designed microemulsion approaches for the straightforward synthesis of CoFe2O4-TiO2nanostructured hybrids.


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