Nano Silica Research Articles

Interplay of physical and textural properties in porous, nanostructured hard‑carbons as electrode materials for non-Faradic energy storage devices

This work presents a systematic investigation on the non-Faradic energy storage ability of non-graphitizable, porosity engineered hard‑carbon nanostructures as electrode materials. The persistent challenge of inducing and tuning porosity in hard‑carbon nanostructures is overcome here, by utilizing dendritic fibrous nano silica (DFNS) as a sacrificial template for uniform and conformal deposition of carbon through thermal chemical vapor deposition, leading to the formation of porosity tuned, nanostructured hard‑carbon florets (NCF). This strategy enables precisely crafted six varieties of NCF with varying yet monodisperse dimensions (NCF 90, NCF 350, NCF 366, NCF 430, NCF 540 and NCF 600), SSA (494–719 m2/g) and textural features such as pore volume (0.67–1.24 cm3/g) and pore diameter (3.83–5.65 nm). In contrast to current understanding, NCF 366 with defect length of 16 nm, defect density of 2.65 × 1011 cm−2, micro- to mesoscale pore ratio of 0.16 and specific surface area of 535 m2/g achieves the highest energy density of 14.6 Wh/kg and power density 10.0 kW/kg, when compared to NCF 90 with higher SSA (719 m2/g) and pore volume (1.24 cm3/g). Thus, this work manifests the critical contributions of tuning the pore structures and optimizing the relative contributions from multi-scale pore structures to achieve high-performing energy storage devices.

The Influence of Nano Silica and Micro Silica on the Compressive Strength of Hybrid Fiber-Reinforced Concrete

The Influence of Nano Silica and Micro Silica on the Compressive Strength of Hybrid Fiber-Reinforced Concrete

Performance of novel engineered materials from nano‐silica incorporated phenol‐formaldehyde‐flax fabric hybrid composite: Thermal, wear, aging and biodegradability analysis

AbstractWith the growing awareness of environmental issues, natural fiber composites have emerged as a viable substitute for conventional polymer composites. The usage of natural fiber reinforced with nano fillers composites has increased significantly in recent years, especially in the building, automotive, and aerospace industries. This research explores the effect of nano‐silica in tribological, thermal behavior, water diffusion properties and biodegradation of flax fabric/phenol‐formaldehyde hybrid composites. We have fabricated the hybrid composites utilizing compression molding technique. The results showed that after reaching the lowest value for 4 nanosilica (NS), the volumetric wear rose when the addition of nano‐silica was increased. However, the volumetric wear decreased as the weight percentage of nano‐silica improved. At lower sliding speeds (1 m/s), the VW value is between 0.06782 and 0.05455 cm3, but at higher sliding speeds (3 m/s), it is roughly 0.09253–0.06187 cm3. The thermal stability was improved for 1 NS, 2 NS, and 3 NS is 1.20%, 1.64%, and 0.71%, respectively. At three different temperatures (30, 60, and 90°C) the impact of nano‐silica on the water diffusion behavior of PF‐flax fabric hybrid composites was examined. 2 NS showed the least amount of water sorption. it was noted that the three coefficients—Diffusion, Sorption, and Permeation‐were all declining when compared to PF‐flax fabric composites devoid of nano‐silica following computing the Arrhenius values, the free energy change was always negative, indicating the spontaneity of sorption in non‐reinforced samples. The tensile strength of every composite in this investigation was marginally changed by the water aging process.

Feasibility of underwater 3D printing: Effects of anti-washout admixtures on printability and strength of mortar

The dispersion and reduction in strength of concrete underwater pose significant challenges to advancing underwater 3D concrete printing technology. While employing anti-washout admixtures holds promise, there is a dearth of relevant research. Herein, a study using various potential anti-washout admixtures, such as micro silica (MS), nano silica (NS), glass fibers (GF), and hydroxypropyl methyl cellulose (HPMC), in mortar mixes was conducted. These mortar mixes were then printed underwater, and their performance in both fresh and hardened states was evaluated to develop underwater 3D printable mortars. The findings revealed that both MS and NS enhance the washout resistance, extrudability, and buildability of fresh mortar, while also improving the flexural, compressive, and bond strengths of hardened mortar. HPMC enhances underwater printability and bond strength, although it may negatively impact flexural and compressive strengths. GF exhibits adverse effects on underwater printability and mechanical properties and is incompatible with HPMC. Noticeably, the combination of MS, NS, and HPMC greatly enhances underwater printability (no dispersion and lowest extrudability/buildability variation coefficients) and mechanical properties (increasing flexural strength and bond strength by 21 % and 151 %, respectively). These findings led to the proposal of several mortar mixes deemed suitable for underwater 3D printing.

Recent advances in nano-modified concrete: Enhancing durability, strength, and sustainability through nano silica (nS) and nano titanium (nT) incorporation

Concrete, essential to global infrastructure, confronts urgent environmental challenges due to its high carbon footprint and resource-intensive production. In response, researchers are exploring nanoparticles, such as nano-silica (nS) and nano-titanium dioxide (nT), to enhance sustainability and performance. This review examines recent advances in their application. Nano-silica, prized for rapid hydration and enhanced strength, emerges as a promising additive. Studies indicate nS accelerates cement hydration, densifies the matrix, and improves durability and impermeability. Silica-based nano-coatings on glass textile-reinforced composites bolster bond strength and resilience. Similarly, nT offers diverse benefits to concrete. Beyond its traditional applications in photocatalysis, nS has been proven to refine pore structure, increase compressive strength, and enhance resistance to elevated temperatures. Additionally, nT adds to the self-cleaning properties of concrete surfaces, making it a promising additive for sustainable construction practices. Despite these advancements, challenges persist in the effective dispersion of nanoparticles within concrete matrices and ensuring their economic feasibility and regulatory compliance. Addressing these challenges will require interdisciplinary collaboration and innovative approaches to optimize dispersion methods, mitigate health risks, and develop robust regulatory frameworks. Future research directions should focus on developing multifunctional nanomaterials capable of imparting multiple desirable properties to concrete simultaneously, such as self-sensing, self-cleaning, and energy harvesting capabilities. Furthermore, efforts to optimize manufacturing processes and scale up production will be essential to realizing the full potential of nano-modified concrete in addressing the sustainability challenges facing the construction industry.

Study on the influence of nano-silica substitution of reactive Si on the properties and hydration process of alkali-activated cementitious materials paste

Nano-silica (NS) is one of the most commonly used nanomaterials in alkali-activated materials (AAMs). Differing from other inactive nanoparticles, as an active Si source, the pozzolanic activity of NS has a significant effect on the hydration reaction and properties of alkali-activated materials. In this study, activated Si in the activator was replaced by NS to prepare alkali-activated slag/fly ash cementitious materials. The effects of different dispersion methods (dry-mix (MD), water dispersion (WD), and activator dispersion (AD)) of NS on the fluidity, rheological properties, and setting time of fresh pastes were investigated. Effects of NS and reactive Si in the activator on the hydration process of alkali-activated slag/fly ash paste were investigated using isothermal calorimetry and the Krstulović-Dabić hydration model. ICP-OES was utilized to study the changing behavior of the composition of the fresh paste pore solution during the hydration reaction. The results show that ions in the pore solution change continuously with the hydration time and eventually stabilize. The stabilized pore solution is mainly composed of OH- and Na+. Different NS dispersion methods have significant effects on paste workability, rheology, and setting time. Activator dispersion can elevate the content of active Si in the activator, causing changes in the hydration process of the paste, especially for the initial hydration period. NS has the most significant effect on the hydration process due to its pozzolanic activity compared to nucleation and filling effects. The Krstulovic-Dabic model can roughly simulate the hydration kinetics possessed of alkali-activated NS/slag/fly ash after entering the accelerated period.

Thermomechanical properties of multifunctional polymer hybrid nanocomposites based on carbon nanotubes and nanosilica

AbstractNanocomposites containing low wt% of oxidized multi‐walled carbon nanotubes (MWCNT‐OXI), nanosilica (NS), and its hybrid (MWCNT‐OXI/NS) in epoxy resin were produced and evaluated. The used nanoparticles were studied by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), and Raman spectroscopy while the nanocomposites were investigated in relation to its morphology, thermal, and mechanical properties. The results demonstrated significant improvements in the storage modulus (E′), glass transition temperature (Tg), and cross link density (CD), for the produced nanocomposites. Increases in thermal conductivity (TC) of up to 85% at 90°C were observed for the nanocomposites containing 1.0 wt% of the hybrid MWCNT‐OXI + NS nanofiller, when compared with neat polymer. It was also verified increases in the resistance to plastic deformation for the nanocomposites, maintained the polymer thermal stability with the addition of these nanoparticles. Finally, the use of MWCNT‐OXI and NS, combined or not, significantly improved the thermal and mechanical properties of polymer, showing multifunctional characteristics for the produced nanocomposites.

Preparation of coal gangue foam concrete modified by nanomaterials: Physical properties, pore structure, and electromagnetic properties

In this study, coal gangue foam concrete (CGFC) was modified with nanomaterials to optimize its electromagnetic wave (EWV) absorption performance. Single-factor test was carried out to explore the effects of nano-silica (NS) and nano-calcium carbonate (NC) on the physical characteristics, hydration products and microstructure of CGFC. The results showed that the compressive strength of CGFC was the optimal when NS and NC were mixed with 1.5 wt% each, in which case the volume water absorption also decreased to the lowest value of 20.61 %. Additionally, compared with the control group, the incorporation of NS significantly accelerated the cement hydration rate. Moreover, the synergistic effect after the addition of NC promoted the cement hydration to generate more ettringite and C-S-H gel, and partly reduced the average pore size of CGFC, thereby improving the pore structure. Finally, the attenuation constant of the composite material can reach 187.92, and the reflection loss can reach −35.6 dB, demonstrating its excellent electromagnetic wave absorption ability.

Review on Performance of Nano Silica and GGBS Blended Self Compacting Concrete

Abstract Concrete has a very significant impact on the atmosphere since Ordinary Portland cement one of the raw material during its production process produces carbon dioxide in large amounts. The impact of concrete structures on the environment may lessen by augmenting the robustness and resilience. The Nano-level arrangement of concrete may be altered by adding a tiny amount of Nano-silica (NS). Since NS forms a paste of calcium silicate-hydrate (C-S-H) through a pozzolanic reaction with calcium hydroxide, it has amassed significant attention when compared to other Nano materials by successfully densifying and strengthening the concrete’s matrix. The present review paper focuses on examining the effects of NS and ground granulated blast furnace slag (GGBS) in various concentrations on the fresh and mechanical properties of Self Compacting Concrete(SCC). It is predicted that this review article will yield fresh concepts for the beneficial use of NS and GGBS in the construction sector and for future research in the field.

Review on Impact of Nano Silica Inclusion on Fresh and Hardened Properties of Self Compacting Concrete.

Abstract In the building sector of days, one of the buzzwords is self-compacting concrete. One of the more sophisticated results of concrete research is SCC, which has the ability to compact on its own weight without exhibiting segregation or bleeding and can flow readily through extremely crowded areas of reinforcement. the assessment of silica’s impact on the properties of both fresh and hardened concrete in self-compacting concrete (SCC). Workability, durability, and mechanical characteristics of self-compacting parks (SCC). In the experiment, various weight percentages of nano-silica—between 1% and 6%—were added to concrete as a cement-priming step. This experiment aims to investigate the effects of varying nano-carbon dioxide contents. Regarding the characteristics of concrete.

Improving storage stability and rheological performance of asphalt rubber modified with nanosilica and Sasobit

In this study, nanosilica (NS) and Sasobit were incorporated into asphalt rubber (AR) binder to produce Si/Sa-AR binder. Various conventional rheological tests were performed to determine the rheological properties of Si/Sa-AR binder. Microscopic tests and four components test were performed to investigate the interaction mechanism of Sasobit and NS with the AR binder. The results show that the combination of AR binder with Sasobit and NS improves the resistance of asphalt to fatigue cracking and permanent deformation. Microscopic images of the AR binder show a ‘dendritic’ structure consisting of multiple swollen crumb rubber (CR) particles and a three-dimensional (3D) network structure, which is reflected in the excellent rheological properties of AR. The addition of Sasobit and NS breaks up the ‘dendritic’ structure while improving the 3D network structure. NS promotes the formation of a homogeneous multiphase system of the modified asphalt binder, which in turn improves the storage stability.

Microstructure and durability properties of high strength self-compacting concrete using micro silica and nano silica

Microstructure and durability properties of high strength self-compacting concrete using micro silica and nano silica

REVIEW: AN EXPERIMENTAL STUDY ON EFFECT OF NANO MATERIALS ON STRENGTH OF CONCRETE AND PLANE STRESS ANALYSIS USING ANSYS SOFTWARE

These days, making efficient and cost-effective use of resources has taken precedence. The main ingredient in concrete, cement has been under criticism in recent years for the quantity of CO2 released during production. Although cement has better mechanical properties, it hasn't been able to live up to the expectations in terms of durability. Owing to cement's shortcomings, scientists started looking into additives that would enhance concrete's qualities while also making it stronger and lighter. Fly ash, silica fume, and other micro particles were added to cementitious materials to improve their compactness, strength, and durability. These additives were also selected because they are eco-friendly by products of industrial waste that may be handled ethically. Fly ash has significant disadvantages because it is not good for initial strength increase and setting time. Because silica fume affects cementitious material performance, researchers have recently become interested in combining it with ceramic waste and rice husk ash. A more effective way to utilize rice husk ash, a by-product of rice cultivation, would be to replace 10% to 15% of cement. Studies have shown improvements in the durability performance of recycled ceramic waste concrete and rice husk ash concrete. There are issues since the RHA production process is quite time-consuming. With the discovery of nano-particles (NP) smaller than 100 nm, researchers have advanced the field of nanotechnology to new levels. The mechanical properties of many materials, including polymers and cementitious materials, can be enhanced by NP. NP is also helpful in the fields of food, engineering, and medicine. This led researchers to investigate the effects of nano-silica (NS) on concrete in further detail. Nano materials can improve the compressive strength and ductility of concrete. In this project an effort will be made to increase the compressive strength of concrete using Nano materials and waste product like GGBS. Also plane stress analysis of concrete cubes and cylinders is to be done using Ansys Software to find deformation, principal stresses and shear stresses. Keywords: Nano –Silica, Nano Titanium dioxide, Ansys, GGBS, Compressive strength

Effect of nano-silica on the flexural behavior and mechanical properties of self-compacted high-performance concrete (SCHPC) produced by cement CEM II/A-P (experimental and numerical study)

The extensive use of cement exacerbates the greenhouse effect by increasing carbon dioxide (CO2) emissions. So, many standards recommend using Portland-composite cement in construction as one of the methods for reducing CO2 emissions, especially cement CEM II/A-P. This paper presents an extensive experimental and numerical study to investigate the effect of micro and nano-silica on the flexural behavior and mechanical properties of Self-Compacted High-Performance Concrete (SCHPC) produced by cement CEM II/A-P. The extensive experimental work consisted of eight mixtures: three with micro-silica (MS), four with nano-silica (NS), and a reference mixture without silica. For both MS and NS, different percentages of adding or replacement content were tested to study their effect on the following: (a) the workability of fresh concrete, (b) concrete compressive strength, (c) splitting tensile strength, (d) flexural behavior including flexural tensile strength, and (e) the optimum percentage of each of the MS and NS to get the maximum structural and economic benefits of using for SCHPC with CEM II/A-P. Also, through a statistical program, these experimental results were used to obtain accurate formulae that could predict both the splitting tensile strength (fsp) and modulus of rupture (fctr) for SCHPC with adding nano-silica. In addition, the numerical study verified the experimental results based on the finite element program ANSYS. The flexure behavior of SCHPC beams is verified using the Microplane model (recently added to ANSYS). The experimental results showed that adding NS is more effective than replacing or adding MS for SCHPC mixture with CEM II/A-P to increase the concrete compressive strength, splitting tensile strength, and flexural tensile strength, especially for the mixture with adding NS content of 4 %. The numerical results showed the ability of the coupled damage-plasticity microplane model to simulate the flexural behavior of the tested SCHPC beams with MS or NS well. This research confirms nano-silica's structural and economical efficiency in the behavior of SCHPC beams. It was found that the optimum percentage of adding NS is 4 % for SCHPC mixtures with CEM II/A-P.

Effects of nano-silica on fracture properties and mechanism analysis of basalt fiber reinforced concrete

The reinforcing effect of basalt fibers (BFs) on the performance of concrete mainly relies on the bridging effect of fibers, while recently, it has been shown that nano-silica (NS) may further enhance this effect. In this paper, three-point bending fracture tests were carried out on BF reinforced concrete (BFRC) to determine the optimal BF condition (i.e. volume content and length). Based on this optimal condition, the effect of NS content on the fracture performance of BFRC was examined from macroscopic and microscopic perspectives. The results indicate that the optimal BF condition for yielding the best concrete performance was 0.2 % volume content and 6 mm fiber length. Based on this condition, NS at 1 % mass content could improve its fracture performance to the best extent. Specifically, the crack initiation toughness, unstable fracture toughness and fracture energy were 1.83 MPa·m0.5, 3.35 MPa·m0.5 and 364.42 N/m, respectively, which were improved by 5.58 %, 15.93 % and 4.97 % compared to BFRC. NS mainly affects the crack propagation mode of BFRC by enhancing the fiber bridging effect or altering the way BFs play a bridging role. NS at an appropriate mass content can delay the occurrence of cracks and improve the deformation ability of BFRC.

Geopolymer concrete containing nanomaterials-a step toward sustainable construction.

Geopolymer concrete (GPC) utilizes industrial wastes such as fly ash, bottom, ash, and slag instead of conventional Portland cement as the primary binder, and thus promote a sustainable solution for bulk concrete works. Nanomaterials (NMs) have often been linked with developing these sustainable high-strength mixes. Furthermore, NMs have been proven to imbibe enhanced physio-mechanical properties, often eliminating the need for thermal curing. This not only reduces total energy demand for concrete production but also offers enhanced durability due to denser inter-particle packing of the mix. This review meticulously summarizes the performance of GPCs dosed with different types of NMs including nano-silica (NS), nano-alumina (NA), nano-titanium di oxide (NT), nano-clay (NC), nano-graphene oxide (NG), and carbon nanotubes (CNT). The reported findings of previous studies were carefully studied and compiled in a systematic manner in terms of physio-mechanical, durability, and microstructural properties. It was observed that addition of NM, in general, leads to a slight reduction in the mix's workability; however, the same can be counteracted by use of suitable superplasticizers. Furthermore, inclusion of NMs in GPC offers the distinct advantage of high density and impermeability, resulting in enhanced mechanical and durability characteristics. Two distinct multi-criteria decision making (MCDM) techniques were employed in this study to statistically analyze the most preferred NM for GPC. It was found that addition of NS (2%) yields the most desirable outcomes. Finally, limitations and challenges associated with production of NM dosed GPC along with scopes for future works are presented toward the end of this review.

Durability performance of superabsorbent polymer incorporated concrete modified by nano-silica addition in seasonal frozen regions

In seasonal frozen regions, ion erosion and freeze-thaw (F-T) cycles threaten pavement concrete durability. This study evaluates the suitability of superabsorbent polymer (SAP) concrete modified by nano silica (NS) for enhancing durability. Tests were conducted to analyze chloride impermeability and frost resistance effects on modified SAP concrete. The coupling impact of ion erosion and freeze-thawing was also evaluated. Mercury intrusion porosimetry (MIP), scanning electron microscopy, and energy dispersive spectrometry were employed to investigate microstructure characteristics. Results demonstrated that NS-modified SAP concrete exhibited high resistance to ion erosion and F-T cycles. Adding 3 % NS reduced the relative dynamic elastic modulus (RDEM) loss by 23.21 % after 300 F-T cycles. The enhancement was more pronounced under the coupled action of ion erosion and freeze-thawing, and the RDEM loss and scaling quantity per unit area of NS-3 % decreased by 13.21 % and 41.48 % respectively, and compressive strength was 28.33 % higher than that of SAP concrete after 135 salt-frost cycles. MIP testing indicated that 3 % NS significantly improved pore structure, reducing deterioration in much harmful pores by 12.82 %. SAP promoted the efficient pozzolanic reaction of NS, generating high-density C-S-H. Additionally, second-hydration products were adsorbed by the ionization of SAP microgel, densifying its shrinkage voids and delaying ITZ width and micro-crack propagation, thereby enhancing concrete durability.

Effect of nano silica on the performance of modified crumb rubber bitumen and asphalt mixtures

Effect of nano silica on the performance of modified crumb rubber bitumen and asphalt mixtures

Controlled Release of Amphoteric Surfactant from Mesoporous Nanosilica To Enhance Natural Gas Production at High Temperatures.

Surfactants are widely used as foaming agents to remove liquid accumulation in gas wells, enhancing natural gas production. The surfactant used in traditional foam sticks was dissolved and released as foam in a short period, especially at elevated downhole temperatures. This often requires the addition of foam sticks to maintain foam. To solve this problem, this study studies the utilization of nano silica to incorporate the amphoteric surfactant, cocamidopropyl betaine (CAB), into the mesoporous structure of silica nanocomposite as foam sticks for controlled release of CAB. Mesoporous nano silica was prepared by a sol-gel acid-catalyzed process with a silica precursor. The formation of nanocomposite solid sticks containing the amphoteric surfactant was achieved by aging and drying. The composite was characterized by various techniques: infrared spectroscopy, thermogravimetric analysis, energy-dispersive spectrometry, scanning electron microscopy, transmission electron microscopy, and small-angle X-ray diffraction. Results showed that 49.3% of CAB was encapsulated within the mesoporous structure of 30-50 nm nano silica. CAB release over time in aqueous solution at 130 °C exhibited 10.1% surfactant left in the nanocomposite after 72 h, as determined by thermal analysis. Surfactant release was systematically evaluated through foam performance tests. The study revealed that CAB could be control-released over 168 h via CAB diffusion from mesoporous silica. This study provides a longer-lasting foam method to enhance gas production by utilizing mesoporous silica as a control release medium for gas well deliquification.

Modification of PVDF membranes using polyvinyl alcohol-crosslinked functionalized nano-silica sheets: High flux and antifouling properties for efficient oil-water separation

BackgroundsOily wastewater is the leading cause of water and environmental pollution, but conventional treatments suffer from complexity and low efficiency, and explicitly deal with oil-in-water emulsions. Polyvinylidene fluoride (PVDF) membranes have shown immense potential for separation applications; however, these membranes rapidly foul during the separation of oily wastewater. MethodsA simple method is introduced to improve the hydrophilicity of PVDF membranes by decorating their surfaces with acrylic acid-modified nano-silica (NS) nanoparticles, whose surface stability is achieved by crosslinking them with polyvinyl alcohol (PVA). Three distinct oils were employed in this study for oil–water emulsion analysis: vegetable oil, diesel oil, and petroleum ether oil. The antifouling abilities and characterization were elucidated using advanced analytical techniques. Significant findingsThe membrane surface became hydrophilic, and the water contact angle reduced from 64 ± 1.45o to 24.3 ± 1.75o. The NS-PVA-PVDF membrane exhibited the oleophobic behavior underwater, with an underwater oil contact angle of 147.6 ± 2.65o. Under optimized conditions, the NS-PVA-PVDF membranes have shown excellent rejection efficiency for different oil-in-water emulsions, including vegetable oil (99.01± 0.64 %), diesel oil (94.61± 0.26 %), and petroleum ether oil-in-water (84.53 ± 0.85 %) emulsions. For a membrane with a 1:3 ratio of PVA to NS particles, organic foulants like humic acid and dye elucidated better performance with 94.79 ± 1.11 and 92.79 ± 1.41 % removal, respectively, along with the flux recovery ratio of 0.96 and 0.92 for humic acid and dye filtration with irreversible fouling of 0.03 and 0.08, respectively. However, the long-term analysis of the optimum membranes showed an overall stable rejection efficiency of >95 % compared with the pristine membrane. The specific rejection efficiency varied for oil emulsion (44.67–50.14 %), humic acid (59.55–67.75 %), and for dye filtration (61.52–73.5 %). These results verify the potential of the modified NS-PVA-PVDF membrane for oil–water separation for practical applications.