Tribological Performance Investigation of a Commercial Engine Oil Incorporating Reduced Graphene Oxide as Additive

We investigated the tribological behavior of commercialized, fully synthetic engine oil upon the incorporation of reduced graphene oxide in seven different concentrations between 0.01 and 0.2 wt %. Stability of the prepared samples was assessed by turbidimetry and dynamic light scattering measurements, and their tribological properties through a reciprocating tribometer, using a steel ball on special cut steel blocks. The addition of 0.02 wt % of reduced graphene oxide led to an improvement of the tribological behavior compared to the pristine engine oil, by significantly lowering the friction coefficient by 5% in the boundary lubrication regime. Both the surfaces and the reduced graphene oxide additive were thoroughly characterized by microscopic and optical spectroscopy techniques. We also verified that a protective layer was formed between the worn surfaces, due to the presence of reduced graphene oxide. Carbon accumulation and various additive elements such as Ca, Zn, S and P were detected on the rubbing surfaces of both the ball and the block through energy-dispersive X-ray spectroscopy. Finally, it was shown that the wear scar diameter on the surface of the steel ball was lower by 3%, upon testing the engine oil sample containing reduced graphene oxide at concentration 0.02 wt %, compared to the control sample.

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Effects of Reduced Graphene Oxide (rGO) at Different Concentrations on Tribological Properties of Liquid Base Lubricants

Lubricants ◽

10.3390/lubricants7020011 ◽

2019 ◽

Vol 7 (2) ◽

pp. 11 ◽

Cited By ~ 6

Author(s):

Jankhan Patel ◽

Amirkianoosh Kiani

Keyword(s):

Graphene Oxide ◽

Physical Properties ◽

Reduced Graphene Oxide ◽

Tribological Properties ◽

High Speed ◽

Friction And Wear ◽

Control Sample ◽

Wear Properties ◽

Reduced Graphene ◽

Friction And Wear Properties

In this study, reduced graphene oxide (rGO) nano platelets were used as an additive to enhance friction and wear properties of oil-based lubricants by preparing three samples at 0.01% w/w, 0.05% w/w, and 0.1% w/w concentrations. To analyze the direct effect of rGO nano platelets on tribological properties, 99.9% pure oil was used as a liquid lubricant. A comparative tribological study was done by performing a ball-on-disk wear test in situ under harsh conditions, which was further analyzed using a non-contact 3D optical profilometer. Morphological evaluation of the scar was done using transmission and scanning electron microscopy (TEM, SEM) at micro and nano levels. The lubricants’ physical properties, such as viscosity and oxidation number, were evaluated and compared for all samples including pure oil (control sample) as per ASTM standards. Findings of all these tests show that adding rGO nano platelets at 0.05% w/w showed significant reduction in friction at high speed and in wear up to 51.85%, which is very promising for increasing the life span of moving surfaces in machinery. Oxidation and viscosity tests also proved that adding rGO nano platelets to all samples does not sacrifice the physical properties of the lubricant, while it improves friction and wear properties.

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Reduced graphene oxide as a protective layer of the current collector of a lithium-ion battery

Russian Journal of Electrochemistry ◽

10.1134/s102319351706012x ◽

2017 ◽

Vol 53 (6) ◽

pp. 622-626

Author(s):

D. Yu. Kornilov ◽

S. P. Gubin ◽

P. N. Chuprov ◽

A. Yu. Rychagov ◽

A. V. Cheglakov ◽

...

Keyword(s):

Graphene Oxide ◽

Lithium Ion Battery ◽

Reduced Graphene Oxide ◽

Protective Layer ◽

Lithium Ion ◽

Current Collector ◽

Reduced Graphene

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Preparation, characterization, and tribological properties of silica-nanoparticle-reinforced B-N-co-doped reduced graphene oxide as a multifunctional additive for enhanced lubrication

Friction ◽

10.1007/s40544-019-0331-1 ◽

2020 ◽

Vol 9 (2) ◽

pp. 239-249 ◽

Cited By ~ 1

Author(s):

Sang Xiong ◽

Baosen Zhang ◽

Shuai Luo ◽

Hao Wu ◽

Zhen Zhang

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Tribological Properties ◽

Silica Nanoparticle ◽

Wear Scar Diameter ◽

Multifunctional Additive ◽

Base Oil ◽

X Ray ◽

Reduced Graphene ◽

Co Doped

AbstractMicrowave-synthesized SiO2-reinforced B-N-co-doped reduced graphene oxide (SiO2-B-N-GO) nanocomposites were characterized by X-ray photon spectroscopy (XPS), X-ray diffraction (XRD), infrared (IR) spectroscopy, and transmission electron microscopy/energy dispersive X-ray (TEM/EDX) analysis. The tribological properties of the SiO2-B-N-GO prepared as anti-wear additives for enhanced lubrication were studied using a four-ball tester. The experiment results indicated that SiO2-B-N-GO exhibits excellent load-carrying, anti-wear, and anti-friction properties in a base oil, especially at the optimal concentration of additives at 0.15 wt%. The wear scar diameter decreased from 0.70 to 0.37 mm and the coefficient of friction was reduced from 0.092 to 0.070, which reductions are attributed to the formation of B-N and graphene layer tribofilms of several tens of nanometers in thickness that prevented direct contact between metals.

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Microstructural characterization and tribological behavior analysis on triethanolamine functionalized reduced graphene oxide

Surface Topography Metrology and Properties ◽

10.1088/2051-672x/abfc60 ◽

2021 ◽

Author(s):

Chenglong Wang ◽

JianLin Sun ◽

Ping Wu ◽

Chenglin Ge ◽

Weixin Meng

Keyword(s):

Graphene Oxide ◽

Behavior Analysis ◽

Reduced Graphene Oxide ◽

Tribological Behavior ◽

Microstructural Characterization ◽

Reduced Graphene

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Enhanced tribological properties of diesel engine oil with Nano-Lanthanum hydroxide/reduced graphene oxide composites

Tribology International ◽

10.1016/j.triboint.2019.105951 ◽

2020 ◽

Vol 141 ◽

pp. 105951 ◽

Cited By ~ 6

Author(s):

Bo Wu ◽

Hui Song ◽

Chuan Li ◽

Ruhong Song ◽

Tianming Zhang ◽

...

Keyword(s):

Graphene Oxide ◽

Diesel Engine ◽

Reduced Graphene Oxide ◽

Tribological Properties ◽

Engine Oil ◽

Lanthanum Hydroxide ◽

Reduced Graphene ◽

Oxide Composites

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Electrical Properties of Textiles Treated with Graphene Oxide Suspension

Materials ◽

10.3390/ma14081999 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1999

Author(s):

Danil Valeriyevich Nikolaev ◽

Zakhar Ivanovich Evseev ◽

Svetlana Afanasyevna Smagulova ◽

Irina Veniaminovna Antonova

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

Vital Signs ◽

Protective Layer ◽

Adhesive Layer ◽

Oxide Coating ◽

Electronic Textiles ◽

Reduced Graphene ◽

Measure Heart Rate ◽

Mechanical Bending

Two-dimensional nanomaterials such as graphene can provide various functional properties to textiles, which have great potential in sportswear, healthcare etc. In this study, the properties of nylon and cotton-based electronic textiles coated with reduced graphene oxide are investigated. After reduction of graphene oxide coating in hydrazine vapor, e-textiles with a resistance of ~350 Ω/sq for nylon, and ~1 kΩ/sq for cotton were obtained. Cyclic mechanical bending tests of samples showed that the resistance increases during bending up to 10–20%. The use of bovine serum albumin as an adhesive layer improved the wash stability for samples with nylon up to 40 washing cycles. The use of BF-6 glue as a protective layer reduced changes in resistance during bending, and improved wash stability of cotton samples. It was shown that the resistance of the obtained samples is sensitive to changes in temperature and humidity. In addition, obtained e-textiles attached to a person’s wrist were able to measure heart rate. Thus, the obtained electronic textiles based on cotton and nylon coated with reduced graphene oxide demonstrates good characteristics for use as sensors for monitoring vital signs.

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