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Global warming and climate change condition are prevailing due to over exploitations of natural resources like fossil fuels, heavy metals, and dumping of wastages in open space. To bring solution to these less dense composite materials using waste biomass is now researched widely by scientists under various applications. The mechanical, tribological, wear, water absorption, and thermal conductivity properties of composite materials reinforced with bronze nanoparticles and areca fiber coated with vinyl silane are investigated in this research work. The novelty of this research study is to investigate how the composite’s characteristics were affected by the vinyl silane–treated bronze nanoparticle. Using a hand layup technique, the fabrication was cured for 24 h at ambient temperature and then post-cured at 120 °C. The AB2 (Areca fiber of 40 vol.%, Bronze nanoparticle of 3 vol.%) composite demonstrated stronger mechanical properties, including a tensile strength of 37.2%, a flexural strength of 22.4%, and an izod impact strength of 36.6% when compared to fiber- and matrix-reinforced base composite AB0 (areca fiber 40 vol.%, resin 60 vol.%, bronze nanoparticle 0 vol.%). In contrast, the AB3 composite displayed remarkable hardness at 84 Shore-D, outstanding wear resistance at 0.011 mm3/Nm, superior thermal conductivity at 0.212 W/mK, and excellent hydrophobicity at 0.12%. Further, when compared to the thermal conductivity of AB3 composite shows 34.2% higher than the thermal conductivity of base composite AB0. Similar such increase in values is attained in other composites compared to AB0 composite. Furthermore, vinyl silane–treated bronze nanoparticles are present in greater volume fractions in AB2 and AB3, which increase reinforcement inside the composite matrix and improve mechanical characteristics. The SEM (scanning electron microscopy) results corroborate that the vinyl silane treatment improved the bond strength of the fiber, filler, and resin. The reinforcement of vinyl silane–treated metallic nanoparticle and natural fiber reinforcement shows better mechanical, wear resistance, and thermal stability property which could be utilized in areas such as automotive, aerospace, defense, and structural applications.

This comprehensive study explores the effect of vinyl silane-treated cellulose on composites made from pineapple fiber-reinforced vinyl ester resin. The main goal was to investigate the influence of vinyl silane treatment on cellulose derived from Amaranthus dubiusroot biomass and its load-bearing properties when combined with pineapple fiber in vinyl ester composites. The cellulose was synthesized from waste Amaranthus dubiusroot biomass through a thermo-chemical process and subsequently treated with vinyl silane. Composites were then fabricated using 40 vol.% pineapple fiber along with varying percentages of the treated cellulose. Mechanical testing showed that incorporating 40 vol.% pineapple fiber significantly improved the composite’s strength and toughness. Further enhancements were observed with the addition of 1.0 vol.% of vinyl silane-treated cellulose, which boosted the mechanical strength due to improved adhesion between the cellulose and the resin matrix. Fatigue testing indicated that the vinyl silane treatment increased the number of cycles the composite could withstand, highlighting better fatigue resistance. However, a potential saturation point was noted at 2.0% cellulose content. Creep resistance tests showed consistent improvement with the addition of reinforcing elements, identifying an optimal cellulose concentration for resisting time-dependent deformation. Thermal analysis (TGA) revealed that the inclusion of treated cellulose affected mass loss and decomposition temperatures, with silane-treated cellulose reducing mass loss due to enhanced bonding and modified cellulose structure. Scanning electron microscopy (SEM) provided insights into the microstructure, emphasizing the critical role of optimizing interfacial adhesion to enhance mechanical properties. In conclusion, the use of vinyl silane-treated reinforcements in the composites led to superior and balanced mechanical properties. These improved composites have potential applications in the automotive, defense, and structural sectors.

In the pursuit of sustainable materials and enhanced composite performance, this study explores the novel incorporation of carbon quantum dots (CQDs) derived from lychee fruit husk waste and discarded castor bean stem fiber into epoxy composites. The effects of these environmentally friendly additives on the load-bearing capacity, fatigue resistance, and water uptake properties of epoxy composites were systematically investigated. These functional additives were incorporated into the epoxy matrix in varying concentrations such as CQDs of 0.25, 0.5, 1.0, and 2.0 vol% and castor bean stem fiber of 30 vol%. From the results, it is noted that composite designation C4 exhibits higher tensile strength of 152 MPa, the flexural strength of 202 MPa, and impact energy of 5.66 J whereas composite C5 exhibits higher hardness of 94 Shore D. Moreover, C4 composite records improved fatigue life cycle counts of 27,144 for 30% UTS, 23,942 for 60% UTS, and 20,036 for 90% UTS. The increment in CQDs vol% results in increased water absorption such that composite designation C5 records 0.328 water absorption percentage. This study demonstrates the potential of utilizing CQDs and castor bean stem fiber as reinforcements for epoxy composites, enhancing performance and addressing sustainability concerns by repurposing agricultural waste. It contributes to eco-friendly material research and highlights the benefits of novel carbon-based additives in polymer composites, paving the way for more sustainable material solutions.

This study presents the synthesis and characterization of flexible polyvinyl alcohol (PVA) composites enriched with jackfruit biocarbon (JFBC) and cobalt nanoparticles (CoNPs) for potential electromagnetic interference (EMI) shielding applications. The cobalt nanoparticles were extracted from Plectranthus amboinicus using the thermo-chemical method. The composites were fabricated using a solution casting method, and their mechanical, dielectric, magnetic, and EMI shielding properties were comprehensively investigated. Mechanical analysis revealed that the incorporation of JFBC and CoNPs significantly enhanced the tensile strength of the PVA matrix. It is noted that PVB4 demonstrates the highest tensile strength among the composite designations, measuring at 63 MPa, along with an elongation percentage of 110. Similarly, composite designation PVB6 delivers higher dielectric properties, thus varying the JFBC and CoNP content, making them suitable for EMI shielding applications. Moreover, the magnetic characterization demonstrated that the inclusion of CoNPs imparted magnetic properties to the composites of about 445.56×10–6emu of saturation magnetization. Similarly, EMI shielding tests resulted remarkable EMI shielding effectiveness for PVB6 and exhibit 46.8 dB for the E band and 53.1 dB for the F band, respectively. Thus, the synergistic effect of JFBC and CoNPs within the flexible PVA matrix presents a promising avenue for the development of lightweight, flexible, and environmentally friendly EMI shielding materials.

In this study, a lightweight hierarchical composite was used in various structural applications by combining fox millet husk ash biosilica particles and low-density Amaranthus dubiusstem fiber–reinforced in epoxy matrix. Studying the shear strength, wear, and thermal conductivity along with hydrophobic behavior of these hierarchical composites is the primary objective of this work. The composites were fabricated using the hand lay-up method, with biosilica particle loading ranging from 0.5 to 2 vol.% and fiber volume of 30%. The results showed that composite containing 1 vol.% biosilica showed a better shear properties tested by different methods viz in-plane shear strength of 154 MPa, lap shear strength of 24.3 MPa, V-notch rail shear strength of 19.4 MPa, and interlaminar shear strength of 27.08 MPa. However, the composite with 2 vol.% of biosilica particles with 30 vol.% fiber loading had better wear properties with coefficient of friction (COF) of 0.26 and a sp. wear rate of 0.007 mm3/Nm. This composite also has lower thermal conductivity value with 0.182 W/mK and lowest contact angle of 84°. However, the composites are in hydrophobic range even after the addition of biosilica. The results obtained clearly demonstrated that these highly toughened and low weight composites could be utilized as a working material for a variety of applications, particularly in the production of automotive components and structural materials for home infrastructure.

The objective of this study was to develop an eco-friendly biocomposite for the replacement of synthetic man-made reinforcement composites using functionalized barely husk biosilica (FBB) and areca chopped fibre (ACF). The biosilica was synthesized via modified thermo-chemical process and functionalized using 3-aminopropyltrimethosyline. After producing composite laminates, using hand layup procedure, the composites were prepared and tested further according to ASTM standards. The results of this study reveals that the mechanical and wear properties of pure epoxy are very less. However, composite, which contains 3.0 vol. % of FBB, gives improved mechanical and wear properties. The coefficient of friction is decreased up to 0.22 along with lowest specific wear rate of 0.014 mm3/Nm by adding 5.0 vol. % of FBB. Moreover, the 5 vol. % of FBB improved the flammability resistance by providing a lowest propagation speed of 8.15 mm/min with no falling drops and cotton lighten, claiming V-0 rating.

Swift heavy ion (SHI) beam irradiation can generate desirable defects in materials by transferring sufficient energy to the lattice that favours huge possibilities in tailoring of materials. The effect of Ag15+ion irradiation with energy 200 MeV on spray deposited V2O5thin films of thickness 253 nm is studied at various ion doses from 5 × 1011to 1 × 1013ions/cm2. The XRD results of pristine film confirmed orthorhombic structure of V2O5and its average crystallite size was found to be 20 nm. The peak at 394 cm−1in Raman spectra confirmed O–V–O bonding of V2O5, whereas 917 cm−1arise because of distortion in stoichiometry by a loss of oxygen atoms. Raman peaks vanished completely above the ion fluence of 5 × 1012ions/cm2. Optical studies by UV–Vis spectroscopy shows decrement in transmittance with an increase in ion fluence up to 5 × 1012ions/cm2. The red shift is observed both in the direct and indirect band gaps until 5 × 1012ions/cm2. The surface topography of the pristine film revealed sheath like structure with randomly distributed spherical nano-particles. The roughness of film decreased and the density of spherical nanoparticles increased upon irradiation. Irradiation improved the conductivity significantly for fluence 5 × 1011ions/cm2due to band gap reduction and grain growth.

Spray deposited Molybdenum trioxide (MoO3) thin film of thickness nearly 379 nm were irradiated with 200 MeV Ag15+ion beam at different fluences (Ø) of 5 × 1011, 1 × 1012, 5 × 1012and 1 × 1013ions/cm2. The X-ray diffraction (XRD) pattern of the pristine film confirms orthorhombic structure and the crystallinity decreased after irradiation with the fluence of 5 × 1011ions/cm2due to irradiation induced defects and became amorphous at higher fluence. In pristine film, Raman modes at 665, 820, 996 cm−1belong to Mo–O stretching, 286 cm−1belong to Mo–O bending mode and those below 200 cm−1are associated with lattice modes. Raman peak intensities decreased upon irradiation and vanished completely for the ion fluence of 5 × 1012ions/cm2. The percentage of optical transmittance of pristine film was nearly 40%, while for irradiated films it decreased significantly. Red shift was observed for both the direct and indirect band gaps. The pristine film surface had densely packed rod like structures with relatively less porosity. Surface roughness decreased significantly after irradiation. The electrical transport properties were also studied for both the pristine and irradiated films by Hall effect. The results are discussed.