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This study investigates the influence of thermoplastic polyurethane (TPU) reinforced with jute cellulose nanofibers (CNFs) on the water absorption and mechanical properties of geopolymer concrete. The integration of TPU/jute CNF nanocomposites into geopolymer concrete is explored as a strategy to enhance both its durability and mechanical performance. Geopolymer concrete, a sustainable alternative to traditional Portland cement concrete, is known for its low carbon footprint, but it suffers from high brittleness and water absorption. The water absorption behavior of the modified concrete was assessed, revealing a significant reduction in water uptake due to the hydrophobic nature of TPU and the reinforcing effect of jute CNFs. Additionally, the mechanical properties, including compressive and flexural strengths, were evaluated to understand the impact of the nanocomposites on the structural integrity of the concrete. The addition of TPU/jute CNFs notably enhanced the splitting tensile strength (63.5%), compressive strength (59%), and water absorption (0.59%) of the composite, indicating a promising route for developing high-performance construction materials. The integration of 6 wt% of TPU/jute CNF nanocomposites was found to be optimal, resulting in a uniform matrix, reduced micro-cracks, and improved compressive strength due to enhanced adhesion between the nanocomposites and the geopolymer matrix. Furthermore, a curing temperature of 100 °C was identified as ideal, minimizing unreacted fly ash and enhancing adhesion strength, while higher temperatures (140 °C) led to material deterioration due to rapid water loss. The findings demonstrate that the addition of TPU/jute CNF nanocomposites not only improves resistance to water penetration but also enhances overall mechanical performance. This supports the development of more sustainable and resilient construction materials, contributing to global efforts to reduce the environmental impact of the construction industry. Future research should focus on the long-term durability of these composites under various environmental conditions to validate their effectiveness in real-world applications. [ABSTRACT FROM AUTHOR]

This study focuses on the modification of natural hydroxyapatite (HAp) derived from clamshell by impregnation with palladium (Pd) at different pH in wet precipitation method to produce photoactive green materials for the degradation of synthetic dyes. It was found that, at pH 10, Pd has been successfully impregnated into HAp lattice with Ca/P ratio of 1.77 and particle distribution size range of 40-470 nm. The impregnation has resulted in the band gap of Pd/HAp at 3.19 eV, as calculated using Tauc's plot from the UV-Vis spectroscopy data of the Pd/HAp. Next, the photocatalytic activities of Pd/HAp were carried out with methyl oranges (MO) as models of water pollutants under UV irradiation. The photodegradation efficiency of the catalyst reached the optimum value of 41.63%, 48.17%, and 43.64% after 120 min of continuous UV irradiation for pH values 8, 10, and 11.5 of Pd/HAp samples, respectively. This study opens a new paradigm in using naturally derived materials as photocatalysts in the reduction of persistent water pollutants at a low cost and green sustainable approach. [ABSTRACT FROM AUTHOR]

With the recent advancement in nanoscience and nanotechnology, carbon nanomaterials have achieved great attention owing to their unique physico‐chemical, mechanical, thermal, and electrical properties. Amongst carbon nanomaterials, carbon nanofibers (CNF) depict a high surface‐to‐volume ratio, enhanced porosity, high mechanical strength, and low weight (light). Carbon nanofibers‐based nanocomposites (CNFN) have been developed for diverse applications. This review illustrates the recent progress in (a) the CNF synthesis via chemical vapor deposition (CVD) or electrospinning, (b) their functionalization with metals and metal oxides nanoparticles, polymers, alloys, and (c) their applications in environmental, industrial, and biomedical domains. Moreover, this study will be helpful for readers to understand CNF production, including the latest trends and fabrication techniques to obtain efficient, cost‐effective, eco‐friendly CNFN, having enhanced surface area with maximum selectivity, reproducibility, and multi‐potential applications. [ABSTRACT FROM AUTHOR]

The dissolving of cellulose under harsh and environmentally unfavorable circumstances is the basis of traditional chemical methods for nanocellulose (NC) or derivatization. Due to the limitations of present methods for dissolving and processing NC, more efficient and ecologically acceptable solvents are required. Because of their excellent thermal and chemical stability, non-flammability, and miscibility with many other solvent systems, ionic liquids (ILs) have emerged as useful and environmentally friendly solvents. Meanwhile, another procedure for producing NC with homogeneous and extremely crystalline characteristics is ultra-sonification. Ultrasound energy is delivered to cellulose chains during ultrasonication by a process known as cavitation, which refers to the development, growth, and collapse of cavities in a liquid medium. Cavitation provides 10–100 kJ/mol of energy in this so-called sonochemistry, which is within the hydrogen bond energy scale. As a result, both catalytic IL treatments and ultrasonication influence the progressive disintegration of NC synthesis. [ABSTRACT FROM AUTHOR]

This study highlights the highly efficient adsorption, photocatalytic properties, and stability of synthesized titanium dioxide (TiO2) photocatalyst incorporated into Chitosan (Cs) and supported onto the glass as substrate toward photodegradation of methyl orange (MO) pollutants. TiO2 was produced using a sol–gel technique, then ex situ synthesized with Cs solution and immobilized on a glass substrate at various weight ratios. The percentages and concentrations of the sorption in dark ambient are calculated in addition to photodegradation of MO under UV light irradiation. At acidic conditions, the photocatalyst with a 2:2 weight ratio of Cs-TiO2 had the optimum dye removal activity (91%). As a result, the work adds to the knowledge of adsorption and photodegradation in the green mitigation of persistent pollutants. [ABSTRACT FROM AUTHOR]

Surface enhanced Raman scattering (SERS) DNA biosensing is an ultrasensitive, selective, and rapid detection technique with the ability to produce molecule-specific distinct fingerprint spectra. It supersedes the long amplicon based PCR assays, the fluorescence and spectroscopic techniques with their quenching and narrow spectral bandwidth, and the electrochemical detection techniques using multiplexing. However, the performance of the SERS DNA biosensor relies on the DNA probe length, platform composition, both the presence and position of Raman tags and the chosen sensing strategy. In this context, we herein report a SERS biosensor based on dual nanoplatforms with a uniquely designed Raman tag (ATTO Rho6G) intercalated short-length DNA probe for the sensitive detection of the pig species Sus scrofa. In the design of the signal probe (SP), a Raman tag was incorporated adjacent to the spacer arm, followed by a terminal thiol modifier, which consequently had a strong influence on the SERS signal enhancement. The detection strategy involves the probe–target DNA hybridization mediated coupling of the two platforms, i.e., the graphene oxide-gold nanorod (GO-AuNR) functionalized capture probe (CP) and SP-conjugated gold nanoparticles (AuNPs), consequently enhancing the SERS intensity by both the electromagnetic hot spots generated at the junctions or interstices of the two platforms and the chemical enhancement between the AuNPs and the adsorbed intercalated Raman tag. This dual platform based SERS DNA biosensor exhibited outstanding sensitivity in detecting pork DNA with a limit of detection (LOD) of 100 aM validated with DNA extracted from a pork sample (LOD 1 fM). Moreover, the fabricated SERS biosensor showed outstanding selectivity and specificity for differentiating the DNA sequences of six closely related non-target species from the target DNA sequences with single and three nucleotide base-mismatches. Therefore, the developed short-length DNA linked dual platform based SERS biosensor could replace the less sensitive traditional methods of pork DNA detection and be adopted as a universal detection approach for the qualitative and quantitative detection of DNA from any source. [ABSTRACT FROM AUTHOR]

ABSTRACT: Poor physical and chemical attraction between nitrile butadiene rubber (NBR) matrix and filler resulted in low thermal properties. Therefore, nanocrystalline cellulose (NCC) as a reinforcement agent was used to increase the heat resistance and thermal stability of NBR composites. The addition of 2 phr NCC increased thermal stability and activation energy of NBR up to 75%. Meanwhile, the storage modulus of composites increased by 12 GPa at the similar loading of NCC. Good interfacial bonds of electrostatic interactions, formation of hydrogen bonds, crystallinity and nanosized of NCC are the main factors contribute to the final properties of NBR/NCC composites. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46594. [ABSTRACT FROM AUTHOR]

Owing to their abundance, high strength and stiffness, and low weight and biodegradability, nanocellulose (NC) is regarded as a promising candidate for the preparation of green composites. The high reinforcing effect assigned to the mechanical percolation phenomenon of NC is due to the stiff continuous networks of cellulosic nanoparticles linked via hydrogen bonding. Compared to nanocrystalline cellulose, NC fibers result in more significant improvement to the modulus, stiffness, and strength as aspect ratio NC fiber is higher compared to NC crystal. Indeed, in the case of biopolymer composites, the reinforcement effect of NC is attributed to the NC‐polymer interactions and the reinforcing effect occurring through effective stress transfer at the NC‐polymer interface. The NC‐reinforced composites tend to become more brittle as the concentration of the reinforcing particles increase up to the saturated level, due to the reduction in surface adhesion between filler and matrix. Due to its promising mechanical and structural stability, NC composites have been used widely in many industrial applications such as food packaging, electronic applications, and tissue engineering. [ABSTRACT FROM AUTHOR]

In this study, Chitosan (Cs) biopolymer was incorporated into TiO2nanoparticles as a support and adsorption site, forming an effective photocatalyst system. The stability and separation ability of the Cs–TiO2photocatalyst system improved as it is further immobilised onto the surface of the glass plate. The surface interactions and the band gap of Cs–TiO2(DP25)/glass photocatalyst have been determined using techniques including FESEM + EDS, FTIR and UV-DR analysis. The photocatalytic activity has been demonstrated on the simulated methyl orange (MO) solution (10 ppm) irradiated under ultraviolet light (6 W,λ = 312 and 365 nm) with different photodegradation parameters such as number of layers, concentration and pH of MO solution. It indicated that Cs–TiO2(DP25)/glass photocatalyst exhibited excellent formation of coordinate covalent bonding between Ti-O to Si-O, Ti-O-to-NH2or Ti-O-to-OH groups. The optimum photodegradation recorded for the Cs–TiO2(DP25)/glass photocatalyst has reached to 78%, with 10 ppm of MO concentration, at a normal pH and 1 h retention time. Meanwhile, optimum adsorption process has been recorded to be more than 70%. It was concluded that the combination of the adsorption and photodegradation process from Cs–TiO2(DP25)/glass photocatalyst has great potential for treating wastewater for other types of organic/inorganic pollutants. [ABSTRACT FROM PUBLISHER]

This review highlighted the developments of safe, effective, economic, and environmental friendly catalytic technologies to transform lignocellulosic biomass into the activated carbon (AC). In the photocatalysis applications, this AC can further be used as a support material. The limits of AC productions raised by energy assumption and product selectivity have been uplifted to develop sustainable carbon of the synthesis process, where catalytic conversion is accounted. The catalytic treatment corresponding to mild condition provided a bulk, mesoporous, and nanostructure AC materials. These characteristics of AC materials are necessary for the low energy and efficient photocatalytic system. Due to the excellent oxidizing characteristics, cheapness, and long-term stability, semiconductor materials have been used immensely in photocatalytic reactors. However, in practical, such conductors lead to problems with the separation steps and loss of photocatalytic activity. Therefore, proper attention has been given to develop supported semiconductor catalysts and certain matrixes of carbon materials such as carbon nanotubes, carbon microspheres, carbon nanofibers, carbon black, and activated carbons have been recently considered and reported. AC has been reported as a potential support in photocatalytic systems because it improves the transfer rate of the interface charge and lowers the recombination rate of holes and electrons. [ABSTRACT FROM AUTHOR]

Taking inspiration from many published chitosan (Cs)-based biocomposites, this article is written to highlight the significant effect of reinforcing and/or blending Cs polymer with the different constituents to increase various properties (mechanical, hydrophilic, thermal, adsorption ability and stability) of Cs without sacrificing any of its positive properties. It is concluded that the properties of Cs biocomposites with a synthetic constituent have contributed to its rigidity since only mechanical interaction occurred at the interfacial region. Instead of physical interactions, the addition of an organic constituent also promoted the chemical interactions at the interfacial region of the Cs biocomposites. This consequently produced Cs biocomposites with synthetic constituents with relatively low strength and stiffness but high resistance to fracture, whereas the ones with an organic constituent have high strength and stiffness but are very brittle. This review also screens the current applications of Cs-based biocomposites in the field of drug delivery, tissue engineering, antibacterial, food packaging, biomedical, metal adsorption and dye removal. [ABSTRACT FROM AUTHOR]