Experimental investigation of usage of POE lubricants with Al₂O₃, graphene or CNT nanoparticles in a refrigeration compressor

• Kayhan Dağıdır and
• Kemal Bilen

Beilstein J. Nanotechnol. 2023, 14, 1041–1058, doi:10.3762/bjnano.14.86

• of the amorphous nature of the material. It is noted that the Al2O3 nanoparticles used in this study have been previously evaluated and similar XRD results were reported in our previous study [21]. Characterization of graphene nanoplatelets The morphological features of the graphene nanoparticles

• sulfuric acid which is utilized for activating the graphene in the graphene synthesis. The crystalline properties of graphene nanoplatelets were determined by XRD analyses. All peaks were measured by XRD and compared with previous studies [26]. The XRD patterns of the graphene nanoplatelet samples are

• recorded in the range of 2θ (15°–75°). The Figure 5 shows that there are two characteristic peaks in the XRD pattern of the graphene nanoplatelets (around 2θ = 27° and 2θ = 54°), which were assigned to the (002) and (004) plane. These peak placements nicely correspond with previous studies [26

On the use of Raman spectroscopy to characterize mass-produced graphene nanoplatelets

• Keith R. Paton,
• Konstantinos Despotelis,
• Naresh Kumar,
• Piers Turner and
• Andrew J. Pollard

Beilstein J. Nanotechnol. 2023, 14, 509–521, doi:10.3762/bjnano.14.42

• sample preparation protocol for GNPref is to obtain a dispersion that contains primarily graphene nanoplatelets [6] without unexfoliated graphite particles. To evaluate this [30][31][32], AFM was carried out to measure the thickness of the flakes from the dispersion. A representative AFM image of the

• contained up to 10 wt % graphite, a measurement protocol that might be considered typical yields a spectrum that is almost indistinguishable from that of graphene nanoplatelets. The averaged spectra were fitted to obtain the peak intensity ratios, as shown in Figure 3. To investigate any differences in the

• of Raman spectroscopy to identify the presence of graphite in a GNP sample, of more relevance is the question of identifying unexfoliated sediment. In typical top-down exfoliation processes, the yield of few-layer graphene or graphene nanoplatelets is very small, often less than 1 wt %. Hence, there

Reliable fabrication of transparent conducting films by cascade centrifugation and Langmuir–Blodgett deposition of electrochemically exfoliated graphene

• Teodora Vićentić,
• Stevan Andrić,
• Vladimir Rajić and
• Marko Spasenović

Beilstein J. Nanotechnol. 2022, 13, 666–674, doi:10.3762/bjnano.13.58

• equivalent to films which have a thickness of 7.6 layers of graphene, which is 2.6 nm. It is likely that reliably conducting films thinner than this cannot be achieved with Langmuir–Blodgett assembly of graphene nanoplatelets. Compared to the work in which the exfoliation time is controlled in the same lab

Enhancement of the piezoelectric coefficient in PVDF-TrFe/CoFe₂O₄ nanocomposites through DC magnetic poling

• Marco Fortunato,
• Alessio Tamburrano,
• Maria Paola Bracciale,
• Maria Laura Santarelli and
• Maria Sabrina Sarto

Beilstein J. Nanotechnol. 2021, 12, 1262–1270, doi:10.3762/bjnano.12.93

• . These included mechanical stretching [19][20], spin coating [21], quenching [22], a combination of the latter two techniques [2], and the addition of external additives to the PVDF matrix, such as metal nanocomposites [14][23], ceramic filler [24], and graphene nanoplatelets (GNPs) and their combination

Effects of temperature and repeat layer spacing on mechanical properties of graphene/polycrystalline copper nanolaminated composites under shear loading

• Chia-Wei Huang,
• Man-Ping Chang and
• Te-Hua Fang

Beilstein J. Nanotechnol. 2021, 12, 863–877, doi:10.3762/bjnano.12.65

• nanoplatelets (GNPs) in a copper matrix the in-plane tensile strength was increased by 26% [17]. Li et al. used graphene nanoplatelets decorated with Ni nanoparticles as addition in a Cu matrix. These Ni-GPL/Cu composites exhibited a 42% increase in ultimate tensile strength (UTS) over that of pure Cu, with

• increase the strength of composites [15][16]. Thus, graphene–metal composites are regarded as important three-dimensional composites. Numerous studies on the enhancement of mechanical properties of graphene–metal composites have been reported. Chu et al. demonstrated that with 10 vol % graphene

Size effects of graphene nanoplatelets on the properties of high-density polyethylene nanocomposites: morphological, thermal, electrical, and mechanical characterization

• Tuba Evgin,
• Alpaslan Turgut,
• Georges Hamaoui,
• Zdenko Spitalsky,
• Nicolas Horny,
• Matej Micusik,
• Mihai Chirtoc,
• Mehmet Sarikanat and
• Maria Omastova

Beilstein J. Nanotechnol. 2020, 11, 167–179, doi:10.3762/bjnano.11.14

• of Mechanical Engineering, Ege University, 35100, Bornova, Izmir, Turkey 10.3762/bjnano.11.14 Abstract High-density polyethylene (HDPE)-based nanocomposites incorporating three different types of graphene nanoplatelets (GnPs) were fabricated to investigate the size effects of GnPs in terms of both

• ’ mechanical properties due to poorer dispersion compared to the others. In addition, the size of the GnPs had no considerable effect on the melting and crystallization properties of the HDPE/GnP nanocomposites. Keywords: electrical properties; graphene nanoplatelets; mechanical properties; polymer matrix

Multicomponent bionanocomposites based on clay nanoarchitectures for electrochemical devices

• Giulia Lo Dico,
• Bernd Wicklein,
• Lorenzo Lisuzzo,
• Giuseppe Lazzara,
• Pilar Aranda and
• Eduardo Ruiz-Hitzky

Beilstein J. Nanotechnol. 2019, 10, 1303–1315, doi:10.3762/bjnano.10.129

• , multicomponent conductive nanoarchitectured materials integrating halloysite nanotubes (HNTs), graphene nanoplatelets (GNPs) and chitosan (CHI) have been developed. The resulting nanohybrid suspensions could be easily formed into films or foams, where each individual component plays a critical role in the

• ) develops highly stable and viscous suspensions after sonomechanical treatment in water. Dispersions of disaggregated sepiolite can efficiently suspend nanoparticles of different topologies and hydrophobic nature such as graphene nanoplatelets (GNPs) and multiwalled carbon nanotubes (MWCNTs) in water [25

• , MWCNTs and poly(vinyl alcohol) [25], sepiolite, graphene nanoplatelets, and biopolymers (e.g., alginate, gelatine) [26] and cellulose or foams of microfibrillated cellulose and starch [47], which exhibit Young’s moduli in the range from 0.1 to 9 GPa. The high stiffness of these materials has been

Graphene–graphite hybrid epoxy composites with controllable workability for thermal management

• Idan Levy,
• Eyal Merary Wormser,
• Maxim Varenik,
• Matat Buzaglo,
• Roey Nadiv and
• Oren Regev

Beilstein J. Nanotechnol. 2019, 10, 95–104, doi:10.3762/bjnano.10.9

• comprising a combination of two different carbon-based fillers, graphene nanoplatelets (GNPs) and graphite. By adjusting the GNP:graphite concentration ratio and the total concentration of the fillers, we were able to fine tune the thermal conductivity and the workability of the hybrid polymer composite. To

• graphene, a two-dimensional sheet of sp2-hybridized carbons, with a much lower filler-to-filler resistance than that of the CNTs [11][24][25]. In recent years, extensive studies have been conducted on graphite and graphene nanoplatelets (GNPs, composed of several graphene layers, with thickness of up to

Two-dimensional carbon-based nanocomposites for photocatalytic energy generation and environmental remediation applications

• Suneel Kumar,
• Ashish Kumar,
• Ashish Bahuguna,
• Vipul Sharma and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2017, 8, 1571–1600, doi:10.3762/bjnano.8.159

• between alternating layers of graphene to form fine layered nanostructures. Self-assembly is also a widely used method for constructing a new class of layered nanostructures with stable, ordered and crystalline structure [58]. In layer-by-layer self-assembly of functionalized graphene nanoplatelets, the

• electrostatic interactions between graphene nanoplatelets are responsible for self-assembly of graphene sheets. In addition to the above-mentioned methods, there are also other efficient methods for synthesis of graphene–metal oxide hybrid nanocomposites, such as solution mixing [59], UV-assisted reduction [13

Graphene–polymer coating for the realization of strain sensors

• Carmela Bonavolontà,
• Carla Aramo,
• Massimo Valentino,
• Giampiero Pepe,
• Sergio De Nicola,
• Gianfranco Carotenuto,
• Angela Longo,
• Mariano Palomba,
• Simone Boccardi and
• Carosena Meola

Beilstein J. Nanotechnol. 2017, 8, 21–27, doi:10.3762/bjnano.8.3

• instead of single graphene layers, self-assembled arrays of nanostructures based on graphene, such as carbon nanotubes [4][5] or graphene nanoplatelets [6][7][8]. The values of GF on the order of 100 or larger can be obtained in these systems, approaching and in some cases exceeding the value 200, which

Reasons and remedies for the agglomeration of multilayered graphene and carbon nanotubes in polymers

• Rasheed Atif and
• Fawad Inam

Beilstein J. Nanotechnol. 2016, 7, 1174–1196, doi:10.3762/bjnano.7.109

• was achieved for amino-functionalized graphene oxide (APTS-GO) [90], while the largest improvement was recorded for surfactant-modified graphene nanoplatelets [60]. SWNTs in superacids: Strong acids such as fuming sulfuric acid and clorosulfonic acid can dissolve and disperse MLG and CNTs in large