Harnessing Bio-Immobilized ZnO/CNT/Chitosan Ternary Composite Fabric for Enhanced Photodegradation of a Commercial Reactive Dye.

Growing demand for sustainable wastewater treatment drives interest in advanced photocatalytic materials. Immobilized photocatalysts hold potential for addressing industrial wastewater organic pollutants, offering substantial surface area, agglomeration prevention, and easy removal. In this study, we successfully immobilized ZnO and carbon nanotubes onto a textile substrate through bilateral esterification and explored their effectiveness as a potent photocatalyst for degrading of commercial textile colorant reactive blue 4 (RB-4) colorant. Findings demonstrated significant improvements in photocatalytic performance upon integrating ZnO and CNTs into the fabric, coupled with chitosan immobilization. The immobilization process of ZnO and CNTs onto the substrate was elucidated through a proposed reaction mechanism, while the appearance of carbonyl peaks at 1719.2 cm-1 in the composite fabric further confirmed bilateral esterification. The as-developed immobilized nano-catalyst exhibited remarkable photocatalytic efficiency with an impressive 93.54% color degradation of RB-4. This innovative approach underscores the immense potential of the ternary immobilized (ZnO/fCNT/chitosan) composite fabric for efficient photocatalytic degradation in textile coloration processes. Exploring the early-stage development of immobilized photocatalysts contributes to safer and more eco-friendly practices, addressing pressing environmental challenges effectively.

Citrous Lime-A Functional Reductive Booster for Oil-Mediated Green Synthesis of Bioactive Silver Nanospheres for Healthcare Clothing Applications and Their Eco-Mapping with SDGs.

Silver nanoparticles (Ag-NPs) are most effective against pathogens and have widely been studied as antibacterial agents in commodity clothing, medical textile, and other hygiene products. However, prolonged utilization of silver and rapid mutation in bacterium stains has made them resistant to conventional silver agents. On the other hand, strict compliance against excessive utilization of toxic reagents and the current sustainability drive is forcing material synthesis toward green routes with extended functionality. In this study, we proposed an unprecedented chemical-free green synthesis of bioactive Ag-NPs without the incorporation of any chemicals. Cinnamon essential oil (ECO) was used as a bio-reducing agent with and without the mediation of lime extract. A rapid reaction completion with better shape and size control was observed in the vicinity of lime extract when incorporated into the reaction medium. The interaction of natural metabolites and citrus compounds with nanoparticles was established using Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. The application of as-prepared nanoparticles on textiles encompasses extended bioactivity to treated fabric with infused easy-care performance. To the best of our knowledge, this is the first reported instance of utilizing bioactive silver nanoparticles as a functional finish, both as an antimicrobial and as for easy care in the absolute absence of toxic chemicals. The easy-care performance of fabric treated with lime-mediated nanoparticles was found to be 141O, which is around 26% better than bare cotton without any significant loss in fabric strength. Furthermore, to enlighten the sustainability of the process, the development traits were mapped with the United Nations Sustainable Development Goals (SDGs), which show significant influence on SDGs 3, 8, 9, and 14. With the effective suspension of microorganisms, added functionality, and eco-mapping with SDGs with the chemical-free synthesis of nanoparticles, widespread utilization can be found in various healthcare and hygiene products along with the fulfillment of sustainability needs.

Chitosan-reinforced gelatin composite hydrogel as a tough, anti-freezing, and flame-retardant gel polymer electrolyte for flexible supercapacitors.

Hydrogel-based electrolytes for flexible solid-state supercapacitors (SSCs) have received significant attention due to their mechanical robustness and stable electrochemical performance over a wide temperature range. However, achieving flame retardancy in such SSCs at subzero temperatures to increase their practical utility remains challenging. Furthermore, there is a need for sustainable and bio-friendly SSCs that use natural polymer-based hydrogel electrolytes. This study reports a novel approach for developing a chitosan-reinforced anti-freezing ionic conductive gelatin hydrogel to meet these demands. Immersion of chitosan-containing gelatin hydrogels in salt solutions caused chitosan precipitation, resulting in composite hydrogels. The precipitated chitosan contributes to the reinforcement of the gelatin hydrogel network, resulting in a high mechanical toughness of up to 3.81 MJ/m3, a fracture energy of 26 kJ/m2, anti-freezing properties (below -30 °C), and excellent flame retardancy without softening. Furthermore, the hydrogel exhibits excellent electrochemical performance, with an ionic conductivity ranging from 72 mS/cm at room temperature (26 °C) to 39 mS/cm at -30 °C. The proposed hydrogel exhibits potential for use in SSC as a gel polymer electrolyte. This study demonstrates a novel strategy for controlling the mechanical, thermal, and electrochemical characteristics of flexible supercapacitors using biological macromolecules.

Tannic acid modified antifreezing gelatin organohydrogel for low modulus, high toughness, and sensitive flexible strain sensor.

Current hydrogel strain sensors have met assorted essential requirements of wearing comfort, mechanical toughness, and strain sensitivity. However, an increment in the toughness of a hydrogel usually leads to an increase in elastic moduli that could be unfavorable for wearing comfort. In addition, traits of biofriendly and sustainability require synthesis of the hydrogels from natural polymer-based networks. We propose a novel strategy to fabricate an ionic conductive organohydrogel from natural biological macromolecule "gelatin" and polyacid "tannic acid" to resolve these challenges. Tannic acid modified the structure of the gelatin network in the ionic conductive organohydrogels, that not only led to an increase in toughness accompanying a decrease in elastic moduli but also headed to higher strain sensitivity and tunability. The proposed methodology exhibited tunable tensile modulus from 27 to 13 kPa, tensile strength from 287 to 325 kPa, elongation at fracture from 510 to 620%, toughness from 500 to 550 kJ/m3, conductivity from 0.29 to 0.8 S/m, and strain sensitivity (GF = 1.4-6.5). Moreover, the proposed organohydrogel exhibited excellent freezing tolerance. This study provides a facile yet powerful strategy to tune the mechanical and electrical properties of organohydrogels which can be adapted to various wearable sensors.

Copper nanoparticles induced, trimesic acid grafted cellulose-an effective, non-hazardous processing approach for multifunctional textile with low chemical induction.

Abstract: Cross-linkers have great importance in textile due to the widespread utilization of cellulosic fibers for clothing. Unfortunately, the acute toxicity of formaldehyde-based resins and the poor performance of non-formaldehyde resins still keep the research door open for scientists in this area. Herein, we demonstrated copper nanoparticles induced trimesic acid grafted cellulose as a sustainable solution for multifunctional easy-care clothing. Our treated fabric presents crease recovery angle value of 248° comparable to that of most promising citric acid-based cross-linkers at the chemical concentration of trimesic acid as low as 2% with a sweeping improvement of around 30% in strength retention, not reported earlier. The relatively low fabric stiffness, without any yellowing, is contributing to the comfort and aesthetic demand while nanoparticles induction promoting utmost antimicrobial need. For the first time, the superiority of the development was validated by interlacing the fabric/finish traits with sustainability building blocks that provide the step forward for rapid industrialization. Furthermore, environmental, health, and safety mapping comparison provides a better understanding of the intensity of hazards that different finishing crosslinkers pose on the environment and public health. With improved performance and superior sustainability, such fabric can act as a preferable alternative to the multifunctional easy-care fabric market. Supplementary Information: The online version contains supplementary material available at 10.1007/s10570-021-04251-5.