Graphene oxide-coated sand for improving performance of cement composites

2021 ◽  
pp. 104279
Author(s):  
Hoan D. Nguyen ◽  
Qianhui Zhang ◽  
Kwesi Sagoe-Crentsil ◽  
Wenhui Duan
Keyword(s):  
Graphene Oxide ◽  
Cement Composites ◽  
Coated Sand

Activation of Structure-forming Properties of Graphene Oxide in Cement Composites

2020 ◽  
Vol 778 (1-2) ◽  
pp. 24-35
Author(s):  
G.D. FEDOROVA ◽  
◽  
G.N. ALEXANDROV ◽  
A.P. SCRYABIN ◽  
◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Cement Composites

scholarly journals Preparation and Mechanical Properties of Graphene Oxide: Cement Nanocomposites

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Fakhim Babak ◽  
Hassani Abolfazl ◽  
Rashidi Alimorad ◽  
Ghodousi Parviz
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Graphene Oxide ◽  
Cement Mortar ◽  
Cement Matrix ◽  
Cement Composites ◽  
Xrd Diffraction ◽  
Calcium Silicate Hydrates ◽  
The Matrix ◽  
Scanning Electron

We investigate the performance of graphene oxide (GO) in improving mechanical properties of cement composites. A polycarboxylate superplasticizer was used to improve the dispersion of GO flakes in the cement. The mechanical strength of graphene-cement nanocomposites containing 0.1–2 wt% GO and 0.5 wt% superplasticizer was measured and compared with that of cement prepared without GO. We found that the tensile strength of the cement mortar increased with GO content, reaching 1.5%, a 48% increase in tensile strength. Ultra high-resolution field emission scanning electron microscopy (FE-SEM) used to observe the fracture surface of samples containing 1.5 wt% GO indicated that the nano-GO flakes were well dispersed in the matrix, and no aggregates were observed. FE-SEM observation also revealed good bonding between the GO surfaces and the surrounding cement matrix. In addition, XRD diffraction data showed growth of the calcium silicate hydrates (C-S-H) gels in GO cement mortar compared with the normal cement mortar.

scholarly journals Investigation of the Effects of Polymer Dispersants on Dispersion of GO Nanosheets in Cement Composites and Relative Microstructures/Performances

Nanomaterials ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 964 ◽  
Author(s):  
Shenghua Lv ◽  
Haoyan Hu ◽  
Yonggang Hou ◽  
Ying Lei ◽  
Li Sun ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Uniform Distribution ◽  
Methacrylic Acid ◽  
Cement Composites ◽  
Polar Groups ◽  
And Performance ◽  
Microstructure And Performance ◽  
Poly Acrylonitrile ◽  
Poly Acrylamide

This study focused on the uniform distribution of graphene oxide (GO) nanosheets in cement composites and their effect on microstructure and performance. For this, three polymer dispersants with different level of polar groups (weak, mild, and strong) poly(acrylamide-methacrylic acid) (PAM), poly(acrylonitrile-hydroxyethyl acrylate) (PAH), and poly(allylamine-acrylamide) (PAA) were used to form intercalation composites with GO nanosheets. The results indicated that GO nanosheets can exist as individual 1–2, 2–5, and 3–8 layers in GO/PAA, GO/PAH, and GO/PAM intercalation composites, respectively. The few-layered (1–2 layers) GO can be uniformly distributed in cement composites and promote the formation of regular-shaped crystals and a compact microstructure. The compressive strengths of the blank, control, GO/PAM, GO/PAH, and GO/PAA cement composites were 55.72, 78.31, 89.75, 116.82, and 128.32 MPa, respectively. Their increase ratios relative to the blank sample were 40.54%, 61.07%, 109.66%, and 130.29%, respectively. Their corresponding flexural strengths were 7.53, 10.85, 12.35, 15.97, and 17.68 MPa, respectively, which correspond to improvements of 44.09%, 64.01%, 112.09%, and 134.79%.

scholarly journals Role of solution chemistry in the retention and release of graphene oxide nanomaterials in uncoated and iron oxide-coated sand

2017 ◽  
Vol 579 ◽  
pp. 776-785 ◽  
Author(s):  
Dengjun Wang ◽  
Chongyang Shen ◽  
Yan Jin ◽  
Chunming Su ◽  
Lingyang Chu ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Iron Oxide ◽  
Solution Chemistry ◽  
Coated Sand

From graphene oxide to reduced graphene oxide: Enhanced hydration and compressive strength of cement composites

2020 ◽  
Vol 248 ◽  
pp. 118699 ◽  
Author(s):  
Guojian Jing ◽  
Jiaming Wu ◽  
Tianyu Lei ◽  
Shuxian Wang ◽  
Valeria Strokova ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Cement Composites ◽  
Reduced Graphene

Dispersion of graphene oxide–silica nanohybrids in alkaline environment for improving ordinary Portland cement composites

2020 ◽  
Vol 106 ◽  
pp. 103488 ◽  
Author(s):  
Junlin Lin ◽  
Ezzatollah Shamsaei ◽  
Felipe Basquiroto de Souza ◽  
Kwesi Sagoe-Crentsil ◽  
Wen Hui Duan
Keyword(s):  
Graphene Oxide ◽  
Portland Cement ◽  
Ordinary Portland Cement ◽  
Cement Composites ◽  
Alkaline Environment

scholarly journals Experimental Study on Mechanical and Functional Properties of Reduced Graphene Oxide/Cement Composites

Materials ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 3015 ◽  
Author(s):  
Ning Zhang ◽  
Wei She ◽  
Fengyin Du ◽  
Kaili Xu
Keyword(s):  
Graphene Oxide ◽  
Electric Conductivity ◽  
Reduced Graphene Oxide ◽  
Cement Composite ◽  
Cementitious Material ◽  
Cement Composites ◽  
Morphological Effect ◽  
Cement Material ◽  
Reduced Graphene ◽  
Electric Shielding

This study develops a novel self-sensing cement composite by simply mixing reduced graphene oxide (rGO) in cementitious material. The experimental results indicate that, owing to the excellent dispersion method, the nucleation and two-dimensional morphological effect of rGO optimizes the microstructure inside cement-based material. This would increase the electric conductivity, thermal property and self-induction system of cement material, making it much easier for cementitious material to better warn about impending damage. The use of rGO can improve the electric conductivity and electric shielding property of rGO-paste by 23% and 45%. The remarkable enhancement was that the voltage change rate of 1.00 wt.%-rGO paste under six-cycle loads increased from 4% to 12.6%, with strain sensitivity up to 363.10, without compromising the mechanical properties. The maximum compressive strength of the rGO-mortar can be increased from 55 MPa to 71 MPa. In conclusion, the research findings provide an effective strategy to functionalize cement materials by mixing rGO and to achieve the stronger electric shielding property and higher-pressure sensitivity of rGO–cement composites, leading to the development of a novel high strength self-sensing cement material with a flexural strength up to 49%.

scholarly journals Effect of Graphene Oxide on Mechanical Properties of Cement Mortar and its Strengthening Mechanism

Materials ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 3753 ◽  
Author(s):  
Yahui Wang ◽  
Jiawen Yang ◽  
Dong Ouyang
Keyword(s):  
Mechanical Properties ◽  
Graphene Oxide ◽  
Cement Hydration ◽  
Strengthening Mechanism ◽  
Cement Composites ◽  
Working Mechanism ◽  
Cement Pastes ◽  
Cement Mortars ◽  
Binder Ratio ◽  
Growth Space

The effects of the water–binder ratio and different graphene oxide (GO) sizes on the mechanical properties of GO-cement composites were systematically studied by preparing GO-cement mortars. The scanning electron microscopy observation (SEM) of the surface and fracture surface of cement pastes was carried out to study the morphology of cement hydration crystals in GO-cement systems under different space conditions. It was found that GO nanosheets significantly improved the compressive, flexural, and tensile strengths of cement mortars. When the dosage of GO nanosheets was 0.03% by weight of cement, the compressive, flexural, and tensile strengths at 28 days increased by 21.37%, 39.62%, and 53.77%, respectively, but GO was not found to be able to regulate the formation of flower-like cement hydration crystals. It was only shown that the growth space had an important influence on the morphology of hydrates. A possible working mechanism was proposed by which GO nanosheets prevented the expansion of microcracks in the cement pastes via a shield effect, thus enhancing the strength and toughness of the cement composites.

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