Tribological performance of IL/(GO-MWCNT) coatings in high-vacuum and irradiation environments

In this paper, we investigated the effect of space irradiation on the lubricating properties of IL/(GO-MWCNT) solid–liquid lubricating coatings. The solid–liquid lubricating coatings consist of ionic liquids (IL), graphene oxide (GO), and multi-walled carbon nanotubes (MWCNT). Irradiation experiments were carried out using ground simulation equipment. Atomic oxygen (AO), ultraviolet (UV), proton (Pr), and electron (El) irradiation alter the composition, structure, morphology, and tribological properties of solid–liquid lubricating coatings. The experimental results show the composition changes induced by irradiation, including the decomposition of ILs lubricants. The damage to the lubricating material was the most serious by Pr irradiation and the least by UV irradiation.

Fabrication and tribological behavior of MnO2/epoxy nanocomposites

Tribology is the study of moving surfaces, and it has a variety of effects on our lives. From an economic point of view, wear is one of the most important aspects of an industry’s viability. Parts of the machine can wear out, and they need to be replaced. This is especially important for polymer-based materials. Therefore, it is important to reduce maintenance costs and improve machine reliability in a variety of engineering applications through proper material selection. The present investigation deals with the fabrication of manganese dioxide (MnO2)/epoxy nanocomposite and investigates its tribological properties. The MnO2/epoxy nanocomposites were fabricated via a solution mixing technique. The phase identification and surface morphology of the sample was examined by X-ray diffractometer and field emission scanning electron microscope, respectively. The mass density, micro-hardness, and specific wear rate data of samples revealed that the mass density, micro-hardness, and wear resistance of the samples increased with the addition of MnO2 in the epoxy matrix. The nanocomposite sample containing 0.5 wt. % MnO2 loading in the epoxy matrix shows higher density, micro-hardness, and wear resistance compared to other samples. The result also shows that with the addition of MnO2 in the epoxy matrix, the coefficient of friction of the samples is increased. The percentage reduction in specific wear rate due to the addition of 0.5 wt. % MnO2 in neat epoxy is 68.10%, whereas the percentage increase in the coefficient of friction is 19.30%. The results of the analysis of variance show the effect of adding wt. % of MnO2 in the epoxy matrix is significant in the tribological responses. The worn surface analysis shows that the fatigue wear mode seems to be the dominating mode of wear for all samples as compared to the other modes of wear. The properties of MnO2/epoxy nanocomposite data revealed that the developed material may be used in the automotive industry as a structural material, fabrication of snow sled, ball bearing housing, or plastic gear materials with adequate lubrication.

Morphological reduction of Fe3O4 by single step hydrothermal synthesis using 1D MnO2 as a template and its supercapacitive behaviour

Nanomaterials have attracted wide attention due to its promising characteristics in contrast to its bulk counterpart. However, its synthesis techniques need to be explored further for its employability in the...

Exploring Surface and Tunneling Properties of Defect-Oriented Quasi-Graphene/Poly(vinylidene fluoride) Nanocomposite Films as Flexible 2D Materials for Electronic Applications

Here, we demonstrate the promising tunneling property of electrons across quasi-graphene/poly(vinylidene fluoride) (PVDF) through the Coulomb blockade region. The melt-mixing technique is used to prepare such a nanocomposite by mixing a nanofiller into the polymer matrix. The structure and surface morphology are studied using X-ray diffraction and field-emission scanning electron microscopy measurements, which show defects oriented in the sample while the binding of matrix with the nanofiller remains highly conductive even upon its binding with the insulating matrix. Tunneling properties of quasi-graphene/PVDF are studied using scanning tunneling microscopy measurements, which indicate high resistance in the Coulomb blockade region. Potential aspects of quasi-graphene/PVDF as a flexible material for device applications are also discussed.

Precise control of morphology of ultrafine LiMn2O4 nanorods as a supercapacitor electrode via a two-step hydrothermal method

Ultrafine 1D LiMn₂O₄ and its promising galvanostatic charge/discharge profiles in KOH/K₃Fe(CN)₆ electrolyte.