Carbon Based Nanostructures

Advances in nanotechnology have provided acoustic researchers with a number of new materials with nano-fibres and nano-pores that can potentially be implemented as an acoustic porous absorber. This paper investigates the acoustic absorption behaviour of carbon nanotube (CNT) arrays, in order to quantify the acoustic characteristics and absorption performance of nanoscopic fibres in comparison with conventional porous materials. Tests were conducted using an impedance tube to measure the normal incidence acoustic absorption coefficient of vertically aligned carbon nanotube (CNT) arrays. Results show that a forest of 3 mm CNT arrays can provide as much as 10% acoustic absorption capability within the frequency range 125 Hz -4 kHz. It was found that CNT arrays, in some cases, may provide better acoustic absorption than conventional porous materials of equivalent thickness and mass. The outcomes of this investigation highlight the potential of nanoscopic fibres for use as light-weight acoustic absorbers.

Surface Treatments to Tailor the Wettability of Carbon Nanotube Arrays. Carbon nanotubes (CNTs) have gained great attention due to their excellent mechanical, electrical, and thermal properties. Carbon nanotube (CNT) arrays attached to solid substrates resemble a nano-carpet and have potentials in a variety of devices.

Surface Treatments to Tailor the Wettability of Carbon Nanotube Arrays. Carbon nanotubes (CNTs) have gained great attention due to their excellent mechanical, electrical, and thermal properties. Carbon nanotube (CNT) arrays attached to solid substrates resemble a nano-carpet and have potentials in a variety of devices.

Nanotubes showed merits including high structural strength-to-weight ratio. However, tubes are less favored regarding stiffness and strength. Nano-I-beams are proposed for improved nano-mechanics. Computationally, the study proposes novel molecular designs of I-beam-like shaped structures. A conformation analysis, molecular dynamics and first principles-based optimization are presented. The study proposes options based on the configuration of the molecular nano-I-beam structure providing less number of planes of symmetry and hence more stability than nanotube-like structures. These designs feature a unique geometrical differentiator of having the walls of the out-of-plane hexagonal motif-based molecular nano-I-beam (C 60 H 46) inclined with different inclination angles enabling promising properties. The stability of the proposed nano-I-beam is proved on par with the corresponding nanotube-like structure. First principles-based evidence is provided on the comparable polarizability and the comparable ability to store energy of the supercell of the crystalline slab nano-I-beam in comparison with the corresponding nanotube. A proposed hybrid octa-hexagonal-cubic molecular nano-I-beam (C 24 H 12) remedies the nano-buckling observed in the alike square-octagonal nanostructure. The molecular nano-I-beam exhibits intrinsic switchability that enables the nano-Ibeam to be a topological semiconductor/insulator. The results show promising electronic and elastic properties of the proposed nano-I-beams that suit several applications such as their use in capacitors, transistors, insulators, batteries, quantization-based nano-devices, solid lubricant additive to grease, toughening fibers of nanocomposites, hydrophobic films, emissions adsorbents, catalytic sensors, PAH materials for space, and sustainable energy. The molecular nano-I-beam provides the base of the corresponding 2-D crystalline slab nano-I-beams.

The purpose of this study was to determine the effects of carbon nanotubes (CNT), reduced graphene oxide (rGO), and a mixture of the (CNT-rGO) on the structural, mechanical, electrical, and optical properties of low (CSL), medium (MCS) and high-molecular (HCS) weight chitosan. The formed films' structure and physical properties were analyzed using swelling, X-ray diffraction, mechanical testing, and SEM micrographs. The 4-Probe technique showed that chitosan electrical conductivity was improved by six orders of magnitude strongly influenced by the CNT addition. The photoluminescence (PL) studies showed that rGO addition induces a non-radiative process in composites and decreases the PL intensity by nearly 43%. The CNTs in CSL and the mixture in CSL present the best electrical, optical, and swelling degree properties. The composites properties and ease of preparation of the films reported in this work make them suitable for optoelectronic applications due to their electrical cond...

This study explores the development of sodium carboxymethylcellulose/carbon nanotube composite coatings for sustainable water sensors. Sodium carboxymethylcellulose (NaCMC), a biodegradable biopolymer, was used as a dispersing matrix for carbon nanotubes (CNT), forming a stable conductive composite. Resistance was analysed in a CNT concentration range of 5-95 wt%, with a percolation threshold at ~ 9.14 wt%. The water interaction was examined under high humidity, droplet deposition, and in full immersion. Coatings with a low

This study aimed to synthesize a carbon nanomaterial (CNM) from municipal sewage sludge (MSS) via controlled pyrolysis followed by acid purification, and to evaluate its application for lead separation from water. The resulting CNM exhibited a regular crystalline structure, high porosity, and particle sizes ranging from 10 to 50 nm. Surface characterization revealed the presence of functional groups such as epoxy, hydroxyl, and carbon-carbon double bonds. Notably, the purification step significantly enhanced the Brunauer-Emmett-Teller (BET) surface area and porosity of the material by factors of 20 and 22.4, respectively. The CNM demonstrated excellent performance in lead removal under varying conditions of pH, stirring speed, initial lead concentration, and adsorbent dosage. Maximum removal efficiency (99.4 %) was achieved at pH 7, 200 rpm, 3 g/L adsorbent, and 10 ppm initial lead concentration. Thermodynamic analysis indicated an endothermic and spontaneous process. Kinetic modeling showed pseudo-first-order behavior at low lead concentrations and pseudo-secondorder behavior at higher levels. Adsorption isotherms fit well with the Langmuir model, confirming monolayer, chemisorption-dominated uptake. Overall, the findings demonstrate that MSS-derived CNMs are not only effective in removing lead from water but also offer a scalable, low-cost solution for repurposing municipal waste into functional materials for real-world wastewater treatment applications.

The aim of this thesis was to improve the knowledge of the soot formation mechanism. Two methods have been used to produce soot particles in controlled conditions: flat flame burner where particles were formed by combustion of rich ethylene/air mixtures and shock tube in which soot was produced by C2H4 pyrolysis at high pressure (5 bar) and in a large range of temperature (1850-2100 K). Both systems have been equipped with a novel technique of scattering at three angles coupled with laser extinction device in order to follow particles growth, to identify different steps of their formation mechanism and to deduce soot volume fraction evolution, soot yield, structure and morphology. In the flame, an overall reduction of soot concentration, mean volume diameter, particles number density was observed when hydrogen was added to combustible mixture. In shock tube, induction delay time of particle formation does not depend on H2 addition. The typical curves of soot yield versus temperature...

The optimization of the poor heat transfer characteristics of fluids conventionally employed in solar devices are at present one of the main topics for system efficiency and compactness. In the present work we investigated the optical and thermal properties of nanofluids consisting in aqueous suspensions of single wall carbon nanohorns. The characteristics of these nanofluids were evaluated in view of their use as sunlight absorber fluids in a solar device. The observed nanoparticle-induced differences in optical properties appeared promising, leading to a considerably higher sunlight absorption. We found that the thermal conductivity of the nanofluids was higher than pure water. Both these effects, together with the possible chemical functionalization of carbon nanohorns, make this new kind of nanofluids very interesting for increasing the overall efficiency of the sunlight exploiting device.

We are reporting the preparation of ZnOnanotabletsat relatively low temperature (1500C) using zinc acetate [Zn(Ac)2], NaOH, cetyltrimethylammonium bromide (CTAB) by solvothermal method. By adjusting the molar ratio of the reactants we obtained nanorods and we also obtained the variation of the dimension of the nanorodsusing hydrazine hydrate as capping reagent. The prepared samples were morphologically recognized as well crystallized.Theaverage diameter of the ZnOnanotabletswere ranging from 500 to 600 nm and the average thickness of the nanotabletswere ranging from 85 to 90 nm. Thelength of ZnOnanorods were ranging from 300 to several micrometersand breadth of theZnOnanorodswere ranging from 80 to 160 nm. The optical properties of the prepared materials have also been studied with the exhibition of its interesting behavior.

Hydrophobic silica aerogel powder and hollow glass microspheres (HGM) were used as fillers for an epoxy adhesive to improve its thermal insulator properties. At 50 wt% of HGM content, the thermal conductivity of the HGM/epoxy composite decreased from 0.182 W/m•K to 0.104 W/m•K. The aerogel/epoxy composite, on the contrary, showed a slight increase in its thermal conductivity, most probably due to the filling of aerogel pores with the epoxy adhesive. Furthermore, it was shown that adhesion values of epoxy composites increase with the addition of aerogel and decrease when HGM was used as the filler material. Realistic numerical finite element method simulations revealed an increase in thermal isolation properties for both HGM/epoxy and aerogel/epoxy composites.

Water collection from natural and industrial fogs has recently been viewed as a viable freshwater source. An interesting outgrowth of the relevant research as focused on arresting of the drift losses (un-evaporated and re-condensed water droplets present in the exhaust plume from industrial cooling towers. Such exploits in fog collection have implemented metal and polyester meshes as fog water collectors (FWC). Fog droplets impinge and deposit on mesh fibers. They coalesce with previously deposited liquid to evolve as larger drops before detaching from the fibers under their own weight, an event largely dependent on the mesh fiber wettability, diameter and its arrangement relative to the fog flow. To better estimate drainage and hence collection from these fibers, the study, focuses on droplet detachment from differently wetted horizontally positioned cylindrical fibers of various diameters, placed orthogonally in the path of an oncoming fog. Droplet detachment volume is found to increase with fiber diameter and fiber surface wettability. Interestingly, in a typical fogging condition, the detachment volume is also found to exhibit a time-dependent behaviour, altering the droplet detachment criteria otherwise predicted from emulation. Our current study sheds light on this unexplored phenomenon.

Real jet fuels are complex mixtures of many organic components, some of which are aromatic compounds. Towards the high-temperature end of the distillation curve, some of the fuel components are multi-ring compounds. A small amount of these high molecular weight species in the fuel could impact soot nucleation in practical engines especially when the fuel is injected as a spray. This work aims to highlight the variation of the sooting propensity of jet fuels as a function of distillate fractions and to examine the validity of a surrogate fuel in emulating soot production from real fuels. Particle size distribution functions and soot volume fractions are studied in a series of laminar premixed stretch-stabilized ethylene flames doped with Jet A, its various distillate fractions, and the 2nd generation MURI surrogate. Soot formation as a result of doping real jet fuel and its distillate fractions is also investigated in counterflow and coflow diffusion flames. The results show that the higher-boiling distillates mostly influence soot nucleation and produce substantially more soot in nucleation controlled flames than the light molecular fraction and jet fuel as received, while such an effect is seen to be small in flames where soot production is controlled by surface growth. The potential impact of distillate fractions on soot nucleation propensities is discussed.

In this study, amine-functionalized MWCNTs (f-MWCNTs) have been investigated as potential material for the removal of Mordant black dye 11 (MBD 11). To evaluate the optimal condition and adsorption capability of the adsorbents (f-MWCNTs), the effect of temperature, pH, adsorbent dosage, and contact time on adsorption rate are examined. The study shows a stronger interaction between the dye and f-MWCNTs. The highest removal efficiency is observed in acidic medium (pH 2) with an initial dye concentration of 50 mg L−1, where 99% of the dye is adsorbed from the medium in 40 min using 0.05 g of f-MWCNTs. Adsorption isotherm and kinetic studies reveal that adsorption occurs by the Langmuir adsorption model and pseudo-second-order adsorption kinetics. According to the thermodynamic parameters, the adsorption exhibits endothermic and spontaneous behavior. Graphical Abstract

A chemically exfoliated graphene, functionalized with hydroxide, was prepared and used as an adsorbent for the removal of amoxicillin from aqueous solutions. This nanocomposite was recovered from chemically exfoliated graphite rods present in spent zinc-carbon batteries. The graphene-OH was determined to have a sheet-like morphology with high surface area (As,BET = 181 m2 g-1) . Its adsorption characteristics were observed at different adsorption time, initial amoxicillin concentrations, and adsorbent dosage to establish the kinetics, isotherm, and optimal adsorption conditions. Pseudo-first-order and pseudo-second-order models were used to study the kinetics, while Freundlich and Langmuir models were used to study the adsorption isotherms. Results showed that amoxicillin adsorption fitted with Langmuir isotherm with higher correlation than the Freundlich isotherm and followed the pseudo-second-order rate model. The removal efficiency increased as the adsorbent dosage was also incre...

This study investigates the impact of combined texturing by micromachining and chemical functionalization on the wetting behavior and water condensation of a metallic surface. The transition from the Wenzel to Cassie-Baxter or impregnated Cassie-Baxter regimes was unveiled. Initially, grooved stainless steel 304 specimens displayed

The presented work focuses on the effect of the deposition of zinc oxide layers by means of spray pyrolysis on the electrochemical and adhesive properties of ZnMgAl-alloy coated steel (ZM). Films were spray coated from aqueous solutions onto substrates at a bulk temperature of 553 K. Film coated substrates were characterized by field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy as well as cyclic voltammetry. Even at small thickness values, the deposited ZnO films show a homogeneous coverage. XPS data revealed the existence of surface carbonate and hydroxyls groups. Peel-tests at high water partial pressure showed that the peel force of epoxy adhesives could be increased from 50 N/m to about 200 N/m based on the ZnO thin film deposition. Finally, cyclic voltammetry revealed an effective inhibition of electrochemical reactions at the electrolyte/oxide interface attributed to the as-deposited ZnO-films.

There are many examples of organic coatings used for corrosion protection. In particular, hydrophobic and super-hydrophobic coatings are shown to give good protection because of their enhanced ability to slow down transport of water and ions through the coating. The purpose of this research is to develop water repellent coating to avoid direct contact between metal and environment corrosive and mitigate corrosion attack at pipeline system. This water repellent characteristic on super-hydrophobic coating was coated by electrodeposition method. Wettability of carbon steel with super-hydrophobic coating (cerium chloride and myristic acid) and oxidized surface was investigated through contact angle and inhibitor performance test. The inhibitor performance was studied in 25% tannin acid corrosion test at 30°C and 3.5% sodium chloride (NaCl). The water contact angle test was determined by placing a 4-μL water droplet of distilled water. It shows that the wettability of contact angle super-hydrophobic with an angle of 151.60° at zero minute can be classified as superhydrophobic characteristic. By added tannin acid as inhibitor the corrosion protection on carbon steel becomes more consistent. This reveals that the ability of the coating to withstand with the corrosion attack in the seawater at different period of immersions. The results elucidate that the weight loss increased as the time of exposure increased. However, the corrosion rates for uncoated carbon steel is high compared to coated carbon steel. As a conclusion, from both samples it can be seen that the coated carbon steel has less corrosion rated compared to uncoated carbon steel and addition of inhibitor to the seawater provides more protection to resist corrosion attack on carbon steel.

Multifunctional materials are accelerating the development of soft electronics with integrated capabilities including wearable physical sensing, efficient thermal management, and high-performance electromagnetic interference shielding. With outstanding mechanical, thermal, and electrical properties, nanocarbon materials offer ample opportunities for designing multifunctional devices with broad applications. Surface and interfacial engineering have emerged as an effective approach to modulate interconnected structures, which may have tunable and synergistic effects for the precise control over mechanical, transport, and electromagnetic properties. This review presents a comprehensive summary of recent advances empowering the development of multifunctional nanocarbon materials via surface and interfacial engineering in the context of surface and interfacial engineering techniques, structural evolution, multifunctional properties, and their wide applications. Special emphasis is placed on identifying the critical correlations between interfacial structures across nanoscales, microscales, and macroscales and multifunctional properties. The challenges currently faced by the multifunctional nanocarbon materials are examined, and potential opportunities for applications are also revealed. We anticipate that this comprehensive review will promote the further development of soft electronics and trigger ideas for the interfacial design of nanocarbon materials in multidisciplinary applications.

Nanocomposites of linear chain of ferroelectric-ferromagnetic crystal structure is considered. It is analyzed theoretically in the motion equation method on the pursuit of magnonic excitations,lattice vibration excitations and their interactions leading to a new collective mode of excitations,the electormagnons. In this particular work, it is observed that the magnetizations and polarizations are tunable in a given temperature ranges for some specific values of the coupling order parameter.

Multi-walled carbon nanotube (MWNT) and combination of single-walled (SWNT) and MWNT were synthesized using pyrolysis assisted chemical vapor deposition method. A single hot zone furnace was used for the synthesis of carbon nanotubes at various temperatures in the range of 750-900C. The as-prepared CNT consisted of carbonaceous impurities and traces of transition metal contents. The as-prepared CNT was oxidized at 500C and then treated with hydrochloric acid which resulted in pure CNT with a purity of 95%. The carbon nanotubes were characterized using field emission scanning electron microscopy (FESEM) and micro-Raman spectroscopy techniques. FESEM images clearly showed the presence of carbon nanotubes and the diameters of the MWNT prepared at various temperatures were in the range of 35-100 nm. The Raman spectroscopy data also showed the presence of D, G and 2D peaks which confirm the presence of CNT.

Single walled carbon nanotubes (SWNTs), with high carboxylic acid content, were chemically modified in order to develop hydrophilic and organophilic analogues. The hydrophilic SWNTs were prepared by wrapping a water-soluble polymer, namely poly (sodium 4-styrene sulfonate) (PSSNa) around the pristine SWNTs, while the organophilic SWNTs were developed by forming amide bonds with oleylamine (C 18 H 37 N). The modification of carbon nanotubes was studied through IR spectroscopy. Moreover, the sorption properties of pristine and modified carbon nanotubes were studied by using adsorbates, which differ in polarity (i.e. water, ethanol and n-hexane). Based on these measurements it is concluded that the sorption behaviour of the SWNTs has been completely modified after the treatment, since the hydrophilic and organophilic carbon nanotubes reveal enhanced selectivity of water and n-hexane respectively.

The long term dispersion stability for an improved thermal conductivity is a challenging issue that needs to be solved for heat transfer applications. Hence, this research investigated that a thin layer of SiO 2 coating (2-5 nm) over WO 3 nanostructures (SiO 2 @WO 3 of different shapes exhibit superior dispersion (0.01%) stability for longer duration (∼3 days) as evident by steady zeta potential (-30 ↔ -60 70 mV), no significant change in particle-size (139 ↔ 147 nm) distribution, density (1 001 ↔ 0 988 g/cm 3 and refractive index (1 335 ↔ 1 332) etc., are indicator for colloidal stability relative to bare WO 3 nanoparticles and bulk SiO 2 aqueous suspension which quickly settles down within 1-2 hours after 30 min sonication at 23 C. Thin Si-OH layer over WO 3 surface imparts superior hydrophilicity, larger surface area for effective solute-solvent (SiO 2 @WO 3 -H 2 O) interaction for improved colloidal stability showing no sedimentation and color change of SiO 2 @WO 3 dispersion (0.01%) even after 3 days due to repulsive interaction between negatively charged Si-O - particles. Thereby, thermal conductivity is found to be quite stable (0 631 ↔ 0 618 W/m • K) up to 3 days, whereas aqueous suspension of bare WO 3 and SiO 2 particles quickly settle down and thermal conductivity rapidly decreased to a value of 0.584 W/m • K for de-ionized water further indicates the significance of SiO 2 coating. Depending on the thickness of SiO 2 layer and volume fraction of SiO 2 @WO 3 , a maximum of 8-10% increment of thermal conductivity was achieved where anisotropic WO 3 displayed always more (∼5%) thermal conductivity than typical spherical nanoparticles.

Multiwalled Carbon Nanotube (MWCNT) reinforced silica aerogel was synthesized in a very simple and cost effective sol -gel method. The process was followed by ambient pressure drying, and then the aerogel material was characterized by XRD, BET, SEM, EDX and FT-IR. 2.3 x 10 -3 wt% MWCNTs were successfully incorporated in sodium silicate based silica aerogel. This metal-free nanocomposite catalyzed a four component organic reaction among 4-hydroxy coumarin, benzaldehyde, phenyl hydrazine, and ethyl acetoacetate for synthesizing medicinally important benzylpyrazolyl coumarin at room temperature. The MWCNT/silica aerogel composite material having easy accessible active sites and high catalytic activity was easily recovered and reused. The aerogel composite when impregnated with ceria offered very efficient and selective reaction methodology.

Mild steels were the most frequently used materials in industries and factories since it possesses unique properties but due to weak environmental changes, these cause deterioration and corrosion to the materials’ surface. To prevent such, protective coatings were applied to protect against corrosion in which by incorporating titanium nanoparticles in polyurethane coatings. Titanium nanoparticles were synthesized using titanium butoxide as a precursor. The obtained nanoparticles were used as an inhibitor mixed with coconut oil-based polyurethane polyol blend against the corrosion on mild steel of 3.5% of sodium chloride solution which has been investigated using the Tafel polarization technique. The polarization curves of the corrosion potential for bare mild steel, along with different amounts of titanium nanoparticles coating, exhibit a positive shift. This shift indicates that the coating film effectively reduces the transport path for the corrosive solution, providing a protective barrier against corrosion. This observation is further supported by the results of the adhesive strength test, which demonstrates that the attachment of the coating films to the metal increases with higher amounts of titanium nanoparticles. This indicates improved adhesion and a stronger bond between the coating and the substrate, enhancing the overall corrosion resistance. The increase of contact angle test confirms the improvement of the coating’s hydrophobicity with the addition of titanium nanoparticles. This suggests the coating repels water more effectively, further contributing to its protective properties against corrosion. Results also show that the addition of 4wt% of titanium nanoparticles has better anti-corrosion properties than the PU CCP alone, and 0.5, 1.0, and 2.0wt% of titanium added.

Over the past 20 years, nanocarbons have become more significant as nanostructured fillers in composites and, more recently, as functional elements in a brand-new class of hybrid materials. Microwave-assisted synthesis and processing is a burgeoning subject matter in materials research with significant strides in the realm of nanocarbon during the last decade. The review examines recent approaches to producing various nanocarbons using microwaves as energy sources, the characterization of such materials for various applications, and their results. The underlying factors supporting the increased performance of such materials or their composites are analyzed and reaction mechanisms are presented wherever necessary. In particular, the recently developed and implanted
approaches to produce porous carbon materials, CNTs and fibers, carbon nanospheres, carbon dots, reduced graphene oxide, corresponding nanocarbon hybrid materials, and the purification and modification of CNTs are discussed. Finally, the reduction of graphene oxide and the preparation of graphene derivative hybrids using solid-state and liquid-state routes such as polyopl, mixed solvents, ionic liquids, and microwave-assisted hydrothermal/solvothermal methods are analyzed in detail. In
addition, the principles of microwave heating in liquid and solid states, the use of metals or their particles as arcing agents or catalysts, and carbonaceous materials as internal or external susceptors during synthesis and modifications are presented in detail.

The rapid evolution of the mechanical industry necessitates reliable and innovative materials. Metal matrix composites (MMCs) have emerged as a leading contender for performing vital roles in this field. Carbon nanostructures, such as graphene and carbon nanotubes (CNTs), are particularly well-suited as reinforcement materials in MMCs. It has been found by recent experimental studies that incorporating CNTs and graphene as reinforcements into metal matrix composites, such as aluminum, magnesium, titanium, nickel, and copper matrices, can significantly enhance the mechanical, thermal, and tribological properties of these materials. This is achieved through various mechanisms, including the restriction of grain growth, hindrance of dislocations, load transfer at interfaces, and mitigation of thermal expansion mismatch. The precise reinforcement and optimization of fabrication techniques have opened up new avenues for achieving uniform nanostructure dispersion and strong interfacial bonding, leading to substantial improvements in quantitative properties. Such advancements in material science hold great promise for the development of high-performance materials with enhanced properties that are vital for various applications, including aerospace, automotive, biomedical, and beyond. The addition of low-carbon nanostructures to polymer matrix, ceramic, and biocomposite systems has also been observed to elicit noteworthy multifunctional improvements. Reinforcing collagen with CNT fibers leads to better mechanical and electrical performance compared to using collagen alone. This critical review provides an insightful and data-driven analysis of the current state of carbon nanostructure (CNTs/graphene)-reinforced metal matrix and biocomposites based on an extensive literature evaluation. The review includes an in-depth examination of the optimized synthesis and processing techniques for CNTs and graphene MMCs, highlighting the impact of reinforcement on their mechanical, thermal conductivity, electrical conductivity, and functional properties. Continued work refining fabrication methods fully leverages their potent multi-functional enhancement capabilities.

Due to its renewable and non-polluting nature, solar energy is often used in applications such as electricity generation, thermal heating, and chemical processing. Solar power plants with surface receivers have low overall energy conversion efficiencies due to large emissive losses at high temperatures. Nano fluids have recently found relevance in applications requiring quick and effective heat transfer such as industrial applications, cooling of microchips, microscopic fluidic applications, etc. Recent papers have indicated that the addition of nanoparticles to conventional working fluids (i.e., Nano fluids) can improve heat transfer and solar collection. The normal efficiency of the solar panels being used is recently found out to be 44.7% and by the use of Nano fluids it can be increased by 10-15% and by Plasmonic Nano fluids by 20% also. Dispersing trace amounts of nanoparticles into common base-fluids has a significant impact on the optical as well as thermo physical properties...

Smart coatings are advanced materials engineered to autonomously respond to external environmental stimuli and offer strong protection against different types of degradation through their self-healing properties. The paper canvases the present state and future prospects of smart coatings within a wide span of applications across industries: automotive, aerospace, construction, electronics, and healthcare. This review clearly points out the potential opportunities of transformative coatings, like nanomaterials, advanced polymers, and hybrid systems, by using new manufacturing techniques such as additive manufacturing and layer-by-layer assembly. This can be done in spite of the obvious challenges related to scalability, durability, and environmental impact through interdisciplinary research and collaboration that will drive this emerging market’s growth. Smart coatings promise a longer service life, lower maintenance costs, and sustainability, essentially by developing eco-friendly alternatives that revolutionize protection and maintenance.

Herein, the review aims to compile some reportable work of researchers carried concerning the use of nanomaterials in the polymeric composites for significant improvements in the properties and to report the application areas of such nanocomposites. Carbon nanotubes, cellulose nanoparticles, titanium dioxide, and other nanoparticles are used in the polymeric composites to enhance their mechanical, electrical, inter-laminar, optical, chemical, electrochemical, electromagnetic shielding, and ballistic properties. Such nanocomposites have a wide range of applications in structural, biomedical, electronics, automobiles, aircraft, oil pipelines, gas pipeline construction, electromagnetic shielding, and protected areas. According to the reported results of researchers, the incorporation of nanomaterials into polymers significantly enhance their properties, which make them able to widen their application areas.

In this study, acrylic-epoxy-based nanocomposite coatings loaded with different concentrations
(0.5–3 wt.%) of graphene oxide (GO) nanoparticles were successfully prepared via the solution
intercalation approach. The thermogravimetric analysis (TGA) revealed that the inclusion of GO
nanoparticles into the polymer matrix increased the thermal stability of the coatings. The degree
of transparency evaluated by the ultraviolet–visible (UV–Vis) spectroscopy showed that the lowest
loading rate of GO (0.5 wt.%) had completely blocked the incoming irradiation, thus resulting in zero
percent transmittance. Furthermore, the water contact angle (WCA) measurements revealed that
the incorporation of GO nanoparticles and PDMS into the polymer matrix had remarkably enhanced
the surface hydrophobicity, exhibiting the highest WCA of 87.55º. In addition, the cross-hatch test
(CHT) showed that all the hybrid coatings exhibited excellent surface adhesion behaviour, receiving
4B and 5B ratings respectively. Moreover, the field emission scanning electron microscopy (FESEM)
micrographs confirmed that the presence of the functional groups on the GO surface facilitated the
chemical functionalization process, which led to excellent dispersibility. The GO composition up to
2 wt.% showed excellent dispersion and uniform distribution of the GO nanoparticles within the
polymer matrix. Therefore, the unique features of graphene and its derivatives have emerged as a new
class of nanofillers/inhibitors for corrosion protection applications.

Successful designing and computation of optimized, large (up to 10 000 atoms), complex structures of isomeric zigzag, armchair, and chiral open-end single-wall carbon nanotubes (SWCNTs) with normalchain C8, C16, C40, C80, and C96 hydrocarbons was performed by means of HyperChem 7.0 (Molecular Dynamics and Molecular Mechanics MM+) and Gaussian 03 (Molecular Mechanics UFF) programs. The diameter of the nanotubes was around 0.4, 0.7, 0.9, 1.1, 1.3, and 1.7 nm. Octane and hexadecane positioned themselves on the nanotube surfaces in the manner influenced by the pattern of the carbon atoms in the tubes, i.e., in the manner dependent on the isomerism of the nanotubes. Longer-chain hydrocarbons usually coiled around the nanotubes, unless they were 0.4 nm in diameter. In such cases a kind of clipshape arrangement of the hydrocarbons on the nanotube surface was noted instead of coiling. The numbers of carbon atoms in one full turn of the hydrocarbon chain coiling around the SWCNT increased wi...

Achieving saturation resistance is a critical obstacle preventing the application of superhydrophobic surface coatings to potential industrial applications including drag reduction, anti-icing, and anti-fouling. In the current study, saturation characterization and saturation resistance are investigated for superhydrophobic nanocomposite coatings. Until recently, there has been little investigation of continuous submersion in water and the effects on superhydrophobic performance. Thus, quantitative characterizations of superhydrophobic performance loss periods under continous surface contact with water were developed with a novel diagnostic method. Additionally, results have shown for the first time that electrolytic reactions on synthetic conductive nanocomposites can extend superhydrophobic performance and resist saturation by as much as 400% in duration.

The effects of adding Mn and Na promoter metals to graphene oxide (GO)-supported iron-based catalysts for Ficher-Tropsch Synthesis (FTS) reactions to olefins at 20 bars were investigated in a 3D-printed stainless steel (SS) Microreactor. While promoter metals encourage reduction of iron oxide to iron to form iron carbide, the active metal catalysts in GO allow hydrogenation of CO. These catalysts were synthesized by layer deposition method and characterized by different techniques. The TEM images show the integration of graphene oxide into the catalysts. The XRD and XPS studies confirmed the crystal structure and oxidation states of the metals. The catalytic activity and product selectivity were studied in the temperature range of 200-350 • Cwith a 2:1 M ratio of H 2 : CO. Higher CO conversion with greater selectivity for olefins was observed in the presence of the promoters. FeMnNa@GO showed better stability than both Fe@GO and FeMn@GO catalysts in time-on-stream studies.

The emissions of volatile organic compounds (VOCs) have hazardous effects on humans and the environment, and hence they should be detected and reduced. In this study, polybenzoxazine (PBZ) and amine-functionalized multiwall carbon nanotube (MWCNT) composites were synthesized as a sensor for VOCs. MWCNT were functionalized with two types of diamines, namely, 1,6-hexanediamine (HDA) and phenylenediamine (PDA). HDA or PDA treated MWCNTs were loaded into the benzoxazine matrix with different weight percentages (0.1, 0.3, 0.5, and 1%). FTIR analysis confirmed the chemical attachment of the two types of diamines on MWCNT. XRD diffraction and scanning electron microscopy (SEM) were used to investigate the nanofillers morphology and clarify the differences between pristine and amine-functionalized MWCNT. Thermal gravimetric analysis (TGA) was used to study the composites' thermal stability and degradation behavior. It was found that, in contrast to neat PBZ, the major degradation temperature of PBZ/0.5%MWCNT-PDA nanocomposites were enhanced by 10%. The electrical conductivity of PBZ was 6.32 × 10-9 , which was enhanced to 6.11 × 10-7 in the composites with 1% MWCNT-PDA. This material was tested as a VOCs sensor for methanol, acetone, and toluene and showed that PBZ/1% MWCNT-PDA composite responded to all the vapors.

Successful designing and computation of optimized, large (up to 10 000 atoms), complex structures of isomeric zigzag, armchair, and chiral open-end single-wall carbon nanotubes (SWCNTs) with normalchain C 8 , C 16 , C 40 , C 80 , and C 96 hydrocarbons was performed by means of HyperChem 7.0 (Molecular Dynamics and Molecular Mechanics MM+) and Gaussian 03 (Molecular Mechanics UFF) programs. The diameter of the nanotubes was around 0.4, 0.7, 0.9, 1.1, 1.3, and 1.7 nm. Octane and hexadecane positioned themselves on the nanotube surfaces in the manner influenced by the pattern of the carbon atoms in the tubes, i.e., in the manner dependent on the isomerism of the nanotubes. Longer-chain hydrocarbons usually coiled around the nanotubes, unless they were 0.4 nm in diameter. In such cases a kind of clipshape arrangement of the hydrocarbons on the nanotube surface was noted instead of coiling. The numbers of carbon atoms in one full turn of the hydrocarbon chain coiling around the SWCNT increased with the diameter of the nanotubes, corresponding to 35, 46, 52, and 64 carbon atoms for 0.7, 1.1, 1.3 and 1.7 nm diameter nanotubes, respectively. However, the comparison of the energy of complexation calculated per one carbon atom of the alkane chain adsorbed on the nanotube surface suggests that in some cases, complexation of long-chain normal hydrocarbons to the carbon nanotube could result in the separation of those nanotubes according to their diameter.

Porous nanocarbons with average particle size 20-40 nm were developed using biowaste oil palm leaves as a precursor. Simple pyrolysis was carried out at 700 °C under nitrogen atmosphere. Obtained porous nanocarbons showed excellent porous nature along with spherical shape. Symmetric supercapacitor fabricated from porous nanocarbons showed superior supercapacitance performance where high specific capacitance of 368 F/g at 0.06 A/g in 5 M KOH were reported. It also exhibited high stability (96% over 1700 cycles) and energy density of 13 Wh/kg. Low resistance values were obtained by fitting the impedance spectra, thus indicating the availability of these materials as supercapacitors electrode. The presented method is cost effective and also in line with waste to wealth approach.

This is to certify that the thesis entitled "Studies on the Mechanical and Dielectric Properties of Unsaturated Polyester Resin Modified by MWCNT, Graphene Oxide and Rubber Seed Oil" is an authentic record of research work carried out by Mrs. Remya Suresh under my supervision and guidance in the

Karbon keras sebagai anoda baterai ion sodium memiliki kapasitas penyimpanan ion sodium yang paling tinggi diantara karbon lunak dan grafit karena struktur ikatan karbonnya paling acak sehingga akan menyediakan ruang lebih luas untuk insersi ion sodium. Material karbon keras dapat diperoleh dari biomassa yang murah dan melimpah ketersediaannya. Penelitian ini bertujuan sebagai studi pendahuluan untuk mengetahui potensi nipah sebagai bahan bahan intermediate karbon keras melalui analisis proksimat dan penentuan bilangan yodium. Tempurung nipah diarangkan pada suhu 300 o C selama 1 jam tanpa aktivasi kimia. Arang yang diperoleh dikarakterisasi kadar air, volatile matter, abu, dan fixed carbon sesuai metode ASTM D1762-84 dengan sedikit modifikasi serta penentuan bilangan yodium sesuai metode dalam SNI 06-3730-1995. Kandungan air dan zat anorganik yang cukup rendah ditunjukkan dengan kadar air dan kadar abu masing-masing 5,00% dan 9,97 %, kadar volatile matter dan fixed carbon sebesar 42,93% dan 42,11%, sedangkan bilangan yodium yang dimiliki sebesar 346,86 mg/g.

Herein, the review aims to compile some reportable work of researchers carried concerning the use of nanomaterials in the polymeric composites for significant improvements in the properties and to report the application areas of such nanocomposites. Carbon nanotubes, cellulose nanoparticles, titanium dioxide, and other nanoparticles are used in the polymeric composites to enhance their mechanical, electrical, inter-laminar, optical, chemical, electrochemical, electromagnetic shielding, and ballistic properties. Such nanocomposites have a wide range of applications in structural, biomedical, electronics, automobiles, aircraft, oil pipelines, gas pipeline construction, electromagnetic shielding, and protected areas. According to the reported results of researchers, the incorporation of nanomaterials into polymers significantly enhance their properties, which make them able to widen their application areas.

Even though significant advantages in the energy-free regulation of temperature are presented, the practical applications of radiative cooling materials in buildings and human surfaces still involve many safety issues, especially for fire hazards of polymer-based materials. Meanwhile, renewable and environmentally friendly materials are urgently needed to develop suitable radiative cooling materials with no adverse environmental impact. Herein, a chitosan-derived composite aerogel film with high solar reflection provided by the addition of melamine-phytic acid (MA/PA) hybrids is designed and prepared, presenting radiative cooling and fireproof performances. The instinct deep-yellow color of chitosan (CS) is successfully shielded by high-reflective MA/PA hybrids, while IR emissivity of up to 90.4 % and solar reflectivity of ~ 89.3 % are achieved. In outdoor environments, this composite aerogel shows sub-ambient temperature drops of ~ 4.3 • C and ~ 3.1 • C in cloudless and cloudy weather, presenting a robust cooling effect. In addition, CS-MA/PA composite aerogel film with 3 mm thickness can isolate the fire of ~ 500 • C, showing superior fire safety attributed to the synergistic flame retardant effects among chitosan, phytic acid, and melamine, which suppress the initial growth of fire and promote the rapid formation of protective char layer. This work provides a bio-based, fire-safe, and radiative cooling material to decrease the energy consumption of temperature regulation with a more environmentally friendly and safer approach, further promoting the practical application of radiative cooling materials.

According to the developed bioinspired method in the one-step procedure, the material with the petal effect was switched to lotus one. Therefore, highly hydrophobic and super-hydrophobic materials with tunable adhesive properties and fractal-like structures were successfully produced with high efficiency (67-84%). The work's essence was to modify chemically selected powders of lanthanide oxides (CeO 2 , Pr 6 O 11 , Nd 2 O 3, and Gd 2 O 3). High effectiveness of the functionalization process with 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FC6) and noctyltriethoxysilane (C6) was proven by various techniques, e.g. XPS, HR-TEM, ATR, XRD, zeta potential. Materials with water contact angle between 143.6 • (CeO 2-C6) and 175.5 • (Nd 2 O 3-FC6) with thermally stable nanolayer (up to 380 • C) were generated. Surfaces functionalized with FC6 possessed a polar component of surface free energy (SFE) close to zero. Water behavior in contact with the modified materials was studied, taking into consideration the unique electron structure of lanthanides assessed by goniometric measurement, also adhesion and spreading pressure were determined. Very low adhesion and polar SFE partly resulted in immediate bouncing of water droplet upon contact with the modified surface. The presented method allows preparing stable materials with a high potential in materials chemistry and modulation of surface features and engineering (e.g. heat transfer fluids, specific coating).

Wettability property of carbon nano-tubes (CNT)-graphene like films have been investigated. In this work, we have studied the wettability of CNT-graphene like film deposited on Ni substrate by Microwave Plasma Enhanced vapor deposition Technique (MWPECVD). Compared to the water contact angles of 77.8°. for bare Ni substrate, the water contact angle of the CNT-graphene like hybrid films is found to be 128.4°. The nanostructures have been deposited at fixed pressure of 20 Torr with different temperature of 500, 600 and 700 °C. The results indicate that wettability properties of nano-structure can be tailored, significantly. The solid surface energy (SE) of composite films was estimated using contact angle measurements. The wettability of CNT-graphene has been studied first time in film form.