Sodium Carboxylate Research Articles

Towards More Sustainable Schiff Base Carboxylate Anodes for Sodium-Ion Batteries.

Bismine sodium salt (BSNa), a Schiff base with two sodium carboxylates, has shown promising electrochemical performance as an anode material. However, its synthesis involves toxic reagents and generates impurities, requiring significant solvent use for purification. This study introduces a novel synthetic method using sodium hydroxide as the sole reagent, which acts as both a base and Na source in the ion exchange step. With this procedure, we reduce the amounts of chemicals, diminish toxicity, improve the purity of the target compound, and use less solvent while maintaining comparable electrochemical performance. Additionally, the procedure is carried out under anhydrous conditions that avoid the undesirable hydrolysis of the imine linkages. In a previous report, the processing of the composite electrode was not established. In this article, we address this issue; the electrochemical performance, specifically the rate capability, is enhanced by processing the electrodes in laminate form rather than powder. As alternative to N-methyl-2-pyrrolidone (NMP), a common but disadvantageous solvent in laminate processing, other solvents were explored by testing acetone (DMK), methylisopropylketone (MIPK), and a DMK-NMP mixture. The remarkable electrochemical performance (specific capacity of 260-280 mAh/g, and capacity retentions higher than 84% at 1C (260 mA/g) remained consistent across these solvents. Furthermore, we investigated replacing copper with aluminum as the current collector to reduce costs and increase the energy density of the battery. While aluminum performed comparably to copper at low specific currents C/10 (26 mA/g), it showed a significant shift in the redox process potentials at higher specific currents.

Acute and sub-chronic toxicity studies of methanol extract of Trema orientalis (Linn) blume in albino wistar rats

BackgroundThe safety potential of the methanol extract of Trema orientalis (TOM) leaf was evaluated in albino Wistar rats using biochemical, haematological, and histological indices in both acute and sub-chronic toxicity studies. MethodsThe animals were managed following the National Institute of Health (NIH) stipulated protocols for handling laboratory animals. The weight of each animal was recorded upon arrival and monitored throughout the study. The animals were allowed to acclimatize for 14 days, after which they were reweighed and randomly distributed into four groups of three female rats (n=12) for acute toxicity studies. Group A was given distilled water, and Groups B, C, and D were given a single dose of 2000, 4000, and 5000 mg/kg bw TOM extract, respectively. On day 15, each animal was anaesthetized and then euthanized. For the sub-chronic toxicity study, animals were randomly distributed into five groups of eight female rats (n=40). They were dosed daily for 28 days. Group A (Negative control group) was given distilled water. Groups B, C, and D had 200, 400, and 800 mg/kg bw TOM extract and Group E (Vehicle control group) were given 0.25 % of sodium carboxyl methyl cellulose (CMC). Five animals were anaesthetized and then euthanized on day 29, while three animals were kept for recovery evaluation for another two weeks without further administration of the extract. Ten organs were excised from each animal and weighed. The liver and kidney were processed for histopathological studies, while the blood samples were collected for biochemical and haematological assays. ResultsFrom acute toxicity studies, the LD50 value of TOM extract was estimated to exceed 5000 mg/kg bw via oral passage. From Sub-chronic toxicity studies, biochemical results showed a significant (p < 0.05) reduction in total protein, albumin, globulin, AST, ALP, and ALT in a dose-dependent manner. Histology of the liver and kidney tissues of all the animals except the kidney of the 800 mg/kg group had no visible lesions; this sets the safety dose for TOM at above 400 mg/kg but below 800 mg/kg. Recovery animals had significantly (p < 0.05) increased total protein, total bilirubin, and ALP and decreased albumin and direct bilirubin levels. ConclusionThis study reports the safety dose of TOM, a reputable medicinal plant extract. This is the first study reporting that the LD50 value of TOM extract exceeds 5000 mg/kg bw via oral passage.

Synthesis and characterization of novel water hyacinth (Eichhornia Crassipes) biodegradable mulch films

In this paper, carboxymethyl cellulose (CMC) and hemicellulose derived from water hyacinth were used to prepare hemicellulose-based biodegradable mulch film by covalent cross-linking and ionic cross-linking in order to expand its application in agricultural production practice. The esterification reaction between hemicellulose, CMC and citric acid resulted in an increase in tensile strength and elongation at break of the membranes. When citric acid was not used as cross-linking agent and the pH was lowered, the sodium carboxylate group was protonated into carboxylic acid group, which provided abundant active sites for chemical cross-linking of hydroxyl group on hemicellulose and hydroxyl group on CMC. Furthermore Zn2+ could cross-link with carboxylic acid group through hydrogen bonding, and when the DS of carboxymethyl group was high, the cross-linking of Zn2+ with Zn2+ was higher, and the conversion into nano ZnO was lower, which was conducive to the uniform distribution and reduction of agglomeration phenomenon in the films. It is favorable for its uniform distribution in the film and reduces the agglomeration phenomenon. The mulch films made from water hyacinth has excellent mechanical properties, light transmittance, water absorption, soil moisture retention and heat preservation, and is biodegradable. This study will provide new ideas for water pollution control and farmland pollution for sustainable agricultural production.

Visual detection of anti‐icing fluids freezing by a low‐temperature viscosity‐sensitive aggregation‐induced emission probe

AbstractIcing detection is critically important for preventing safety accidents and economic losses, especially concerning ice formation from invalidated anti‐icing fluids (water and ethylene glycol) under extreme conditions. Traditional technologies like ultrasonics and capacitor‐antenna face challenges with limited detection areas, lower accuracy, and susceptibility to electromagnetic interference. Here, we introduce a novel viscosity‐ultrasensitive fluorescent probe 4′,4‴‐(2,2‐diphenylethene‐1,1‐diyl) bis‐(3,5‐dicarboxylate) (TPE‐2B4C) based on AIEgens for monitoring ice formation of anti‐icing fluids in low‐temperature environments. TPE‐2B4C, consisting of four sodium carboxylate groups and multiple freely rotating benzene rings, demonstrates outstanding solubility in anti‐icing fluids and exhibits no fluorescent background signal even at low temperatures (&lt;−20°C). Upon freezing, TPE‐2B4C relocates from the water phase to higher viscosity ethylene glycol, causing restriction of benzene rings and a significantly increased green fluorescence signal. TPE‐2B4C can successfully determine whether the anti‐icing fluids are icing from −5 to −20°C with a high contrast ratio. Due to its simple setup, fast operation, and broad applicability, our new method is anticipated to be employed for rapid, real‐time, and large‐scale icing detection.

Quantitative measurement of sodium emissions during oxy-fuel combustion of a beech wood biomass particle using laser-induced breakdown spectroscopy

Oxy-fuel biomass combustion in a circulating fluidized bed is a clean and sustainable biomass utilization technology. Woody forest biomass is considered a promising source of renewable energy because of its widespread availability across the globe. However, effective biomass utilization in thermal power plants is largely limited by severe ash deposition and corrosion of heat transfer surfaces due to alkali metal and chlorine emissions during biomass combustion. In this study, laser-induced breakdown spectroscopy (LIBS) was applied to detect in-situ gas phase sodium (Na) emission during single particle combustion of widely available forest biomass, namely, beech wood. The operating conditions simulate the thermo-chemical conditions relevant to a fluidized bed combustor system, where the operating temperature varies between 1073K–1273K. This work aims to investigate the effect of O2 concentration, CO2 (oxyfuel environment), and particle size on the emission of sodium during the combustion of a single beech wood particle. The unresolved sodium doublet was used as the LIBS signal to quantify sodium emission concentration.Oxygen concentration is the most critical parameter affecting Na emissions, and an increase in O2 concentration led to higher Na emissions. It is observed that there is a significant reduction in the emission of Na in an O2/CO2 environment as compared to an O2/N2 environment. It is hypothesized that this drop in Na emissions in O2/CO2 environment could be due to lower particle temperatures caused by the lower diffusivity of O2 in CO2 as well as the endothermic gasification reaction in high CO2 environments. In addition, it is reported that the dissociation of sodium carboxylates and carbonates in the biomass matrix to release gaseous Na due to thermal decomposition is retarded at higher CO2 concentrations which could explain the drop in Na emissions. The effect of biomass particle size is pronounced mainly at lower concentration of O2 where, larger particles keep Na trapped in its matrix, however, at higher O2 concentrations (30%), the effect of particle size on Na emission is negligible.

Long-Term Thermal Stability of Ionic Surfactants for Improving Oil Production at High-Salinity High-Temperature Conditions.

Surfactants with stable chemical structures and robust ability are required to lower interfacial tension and stabilize emulsions for successful chemical injection applications. This work selected six surfactants, dodecyl carboxylic sodium (LAS), dodecyl sulfonate dodecyl sodium (SLS), dodecyl sulfate sodium (SDS), dodecyltrimethylammonium bromide (DTAB), 3-(N,N-dimethylmyristylammonio) propanesulfonate (SB3-14) and a sulfobetaine formulation (PCT-10), and systematically investigated the ionic-type effects on thermal stability at 95 °C for 150 days in high-salinity water (total dissolved solids (TDS) = 57,600 ppm). With characterizations of aged samples performed through a spinning drop tensiometer, high-performance liquid chromatography, and infrared spectroscopy, it can be seen that the long-term stability sequence of ionic surfactants in solutions is sulfobetaine ≈ quaternary ammonium > sulfonate > sulfate > carboxylate. The carboxylate possibly precipitates out from the solution in the acid form, and the sulfonate and sulfate decompositions are due to the hydrolysis of the anionic head, forming alcohol and NaHSO3/NaHSO4. Obvious decomposition of sulfobetaine and quaternary ammonium was not observed, but these molecules might suffer the elimination of the ionic head, forming the corresponding alkene and amine. The results also show that the dissolved oxygen in the solution preparation significantly sped up the degradation of sulfonates. At last, the emulsion stability tests of crude oil in surfactant solutions showed that sulfobetaine surfactants retained the highest emulsifying ability after thermal aging and thus are promising candidates for long-term chemical injection in high-temperature high-salinity reservoirs.

Could Commercially Available Aqueous Binders Allow for the Fabrication of Highly Loaded Sulfur Cathodes with a Stable Cycling Performance?

In this review, the application of five commercially available aqueous-based binders including sodium carboxyl methyl cellulose (CMC), polyacrylic acid (PAA), polyvinyl alcohol (PVA), polyethylene oxide (PEO), and polyethyleneimine (PEI) as well as some representative custom (or purpose) synthesized functional binders used in lithium sulfur (Li-S) batteries is summarized based on the main evaluation criteria of cycling capacity, battery lifetime, and areal sulfur loading (and, consequently, energy density of the battery). CMC with SBR (styrene butadiene rubber) has been reported with promising results in highly loaded sulfur cathodes (&gt;5 mg cm−2 sulfur loading). PVA and PEI were confirmed to provide an enhanced adsorption of lithium polysulfides due to the interaction with hydroxyl and amine groups. No competitive advantage in electrochemical performance was demonstrated through the use of PAA and PEO. Water-based binders modified with polysulfide-trapping functional groups have complex fabrication processes, which hinders their commercial application. In general, achieving a high capacity and long cycling stability for highly loaded sulfur cathodes using commercial aqueous-based binders remains a significant challenge. Additionally, the scalability of these reported sulfur cathodes, in terms of complexity, cost, and stable electrochemical cycling, should be evaluated through further battery testing, particularly targeting pouch cell performance.

Design, Formulation, and Evaluation of Lisinopril Mucoadhesive Buccal Patches by Using the Combination of Natural Polymers

The main objective of present investigation to formulate and evaluate mucoadhesive buccal patches of Lisinopril using solvent casting method. Sodiumalginate combined with Sodium carboxyl methyl cellulose, HPMC, and Carbopol934 in different proportions were used as a mucoadhesive polymer and Propyleneglycol used as a plasticizer as well as penetration enhancers. The formulated Buccal patches of Lisinopril were evaluated on the basis of Thickness, Weight uniformity, folding endurance, swelling Studies, Surface pH Determination, Percentage Moisture loss, Drug content Uniformity, Ex-Vivo Mucoadhesive strength, In Vitro Drug Release, Ex- vivo permeation study. By compatibility study there is no chemical interaction between drug and excipients used. All prepared buccal patches were transparent, smooth, consistent and flexible. The surface pH of all formulations was found to be almost in neutral pH and no mucosal irritation was expected. Among all the formulations, F6 showed maximum swelling index as 25.01%. The optimized formulation F6 also showed satisfactory, Mucoadhesive strength (5.1kg/cm2), drug content (98.75), and Ex-Vivo permeation (82.03%). In-Vitro drug release of optimised formulation (F6) was found to be 75.12 at the end of 8 hrs. Drug release mechanism was determined by plotting release data to Higuchi and Korsmeyer-Peppas model. All the formulations are best fitted to Korsmeyer-Peppas model and according to this model the drug releases from theses patches may be controlled by diffusion with super case-II transport.

Ruthenium(II)‐Catalyzed Selective C(sp2)−H Acyloxylation of 2‐Aroyl‐Pyridine Derivatives with Sodium Carboxylate

AbstractA ruthenium‐catalyzed C(sp2)−H acyloxylation of 2‐aroyl pyridine derivatives with simple sodium carboxylate utilizing transformable directing groups is described. This protocol features broad functional group tolerance and chemo‐ and regio‐selectivity, providing the acyloxylation products in 45%‐84%yield. Furthermore, the synthetic utility of this protocol was demonstrated by the late‐stage functionalization of pharmaceutical compounds. Notably, the acyloxylation products could be further transformed into a variety of useful heterocycles under mild conditions.

Bioinspired phosphorus-free and halogen-free biomass coatings for durable flame retardant modification of regenerated cellulose fibers

Inspired by mussel adhesion and intrinsic flame retardant alginate fibers, a biomass flame retardant (PPCA) containing adhesive catechol and sodium carboxylate structure (-COO−Na+) based on biomass amino acids and protocatechualdehyde was designed to prepare flame retardant Lyocell fibers (Lyocell@PPCA@Na). Furthermore, through the substitution and chelation of metal ions by PPCA in the cellulose molecular chain, flame retardant Lyocell fibers chelating copper and iron ions (Lyocell@PPCA@Cu, Lyocell@PPCA@Fe) were prepared. Compared with the original sample, the peak heat release rate (PHRR) and total heat release (THR) for modified Lyocell fibers were significantly reduced. In addition, the modified sample exhibited a certain flame retardant durability. TG-FTIR analysis showed that the release of flammable gaseous substances was inhibited. The introduction of Schiff bases and aromatic structures in PPCA, as well as the decomposition of carboxylic metal salts were beneficial for the formation of char residue containing metal carbonates and metal oxides to play the condensed phase flame retardant effect. This work develops a new idea for the preparation of eco-friendly flame retardant Lyocell fibers without the traditional flame retardant elements such as P, Cl, and Br.

Rapid preparation of binary mixtures of sodium carboxylates as anodes in sodium-ion batteries.

Sodium-ion batteries are emerging as a sustainable solution to tackle the growing global energy demands. In this context, organic electrode materials complement such technologies as they are composed of earth-abundant elements. As organic anodes, sodium carboxylates exhibit promising applicability in a wide range of molecules. To harness the advantages of individual systems and to minimise their limitations, in this work, an approach to form binary mixtures of sodium carboxylates using one-pot, microwave-assisted synthesis is presented. The target mixtures were synthesised in 30 min with disodium naphthalene-2,6-dicarboxylate (Na-NDC) as a common constituent in all. Both components in all mixtures were shown to participate in the charge storage and had a considerable effect on the performance characteristics, such as specific capacity and working voltage, in half and full cell formats. This approach opens a new avenue for enabling organic materials to be considered as more competitive candidates in sodium-ion batteries and promote their use in other material classes to overcome their limitations.

A MOF-doped molecularly imprinted polymer/MOF hybrid gel incorporating with pH-buffering sodium acrylate for practical detoxification of organophosphorus nerve agents

The fatal toxicity of organophosphorus nerve agents (ONAs) and the realistic condition of chemical attack occurring place trigger the urgent need to develop catalyst materials with degrading ability under the natural environment without bulk water and bases. Here, we strategically design a molecularly imprinted polymer (MIP)/MOF hybrid catalyst material by integrating enzyme-mimic MIP with Zr-MOF UiO-66-NH2 which demonstrate promising catalytic performance for degradation of ONAs. Furthermore, sodium acrylate functions as a hydrophilic and alkaline functional unit together with pyridine-amidoxime based functional monomers (PAAO) to copolymerize into molecularly imprinted polymeric network. The basic sodium carboxylate groups were installed near the active sites to provide appropriate alkaline microenvironment, non-bulk water and acid buffer capacity for the catalysis in pure water. The resultant MIP/MOF composite catalyst demonstrate outstanding catalytic activities in both liquid and solid phase hydrolysis of ONAs. Specifically, the half-life of liquid phase hydrolysis catalyzed by MIP/UiO-66-NH2-0.5 achieves 9.4 min for diethyl-4-nitrophenyl phosphate (DENP) and 10 min for dimethyl 4-nitrophenyl phosphate (DMNP), and solid-state hydrolysis present rapid degradation efficiency with a half-life of 28.6 min. In addition, composite catalyst MIP-Ag/UiO-66-NH2-0.5 that retains substrate selectivity of MIP, enables the simultaneous degradation of two types of organophosphorus substrates (phosphate and thiophosphate) by MIP and MOF in a synergistic way. Summarily, this work displays promising potential of MIP/MOF hybrid enzyme-like catalyst as effective and practical material for the practical protection and detoxification of organophosphorus nerve agents.

Electromediated Oxidation of Hydrolysed Bacterial Cellulose

The state-of-the-art method to isolate cellulose nanofibres employs a 2,2,6,6-Tetramethylpiperidinyloxyl (TEMPO)/NaBr/NaClO system, where the primary alcohols on the surface of cellulose microfibrils are oxidised. However, the large consumption of hypochlorite in this system makes it problematic for industrial implementation. Previously, electrochemical oxidation with a TEMPO catalyst has been reported for the preparation of cellulose nanofibres. Here, we present a study on the electromediated oxidation of bacterial cellulose (BC), the purest form of cellulose. BC has been used in a hydrolysed form, enabling the electromediated preparation of cellulose nanocrystals (CNCs), which is generally deemed even more costly than the preparation of cellulose nanofibres.In this work, the electromediated oxidation and cyclic voltammetry were performed in an electrochemical cell, which featured three electrodes: A Hg|Hg2SO4|K2SO4 reference electrode, a titanium net counter electrode, and a carbon foam working electrode, offering a high surface area. A static potential of 0.5 V was applied during the chronoamperometry and explored oxidation times were 3, 5, 9, 12 and 24 h.Using a TEMPO catalyst, the electromediated oxidation was applied to hydrolysed and non-hydrolysed BC fibres in a pH 10 buffer. The C6 primary hydroxyls of BC were successfully converted to sodium carboxylate groups. By the application of the TEMPO electro-mediated oxidation to hydrolysed BC for 9 h, high carboxylate and aldehyde concentrations of 1.4 and 0.3 mmol/g, respectively, were formed in the oxidized fibre. The carboxylate and aldehyde content was determined by a conductometric titration method. Surface morphologies after oxidation were investigated, showing alteration of the microfibril morphology for BC and the production of cellulose nanocrystals for hydrolysed BC. Hence, we present an effective and environmentally friendly route, which is particularly suitable for the preparation of cellulose nanocrystals.

Development of an eco-friendly dust suppressant based on modified pectin: experimental and theoretical investigations

This study aims to develop eco-friendly composite dust suppressants to mitigate the adverse impact of coal mine dust on worker health and the environment. An environmentally friendly dust suppressant with bonding and wetting effects was prepared by combining modified pectin as a binder and a non-toxic surfactant as a wetting agent. Optimal ratios of sodium carboxylate ethoxylate sulfate (LMES), isomeric alcohol ethoxylate (XL-70), and modified pectin were determined through experiments. The modified pectin exhibited stronger wetting properties on coal powder due to its increased hydrophilicity. Wetting performance tests confirmed its excellent performance. Film-forming and scanning electron microscope tests demonstrated the dust suppressant's ability to bond with coal dust, resulting in a smooth surface and closely connected particles. Environmental tests showed its non-toxicity and degradability. Spraying dust reduction tests revealed a significant average increase of 40.51 % in dust reduction rate compared to water spraying, effectively lowering dust concentration. These findings have practical implications for the development of eco-friendly composite dust suppressants and controlling underground dust in coal mines, benefiting worker health and environmental sustainability.

Synthesis and characterization of in-situ self-growth mineralization-responsive dispersed gel nanoparticles

This study employed a reverse emulsion method to prepare dispersed nanoparticle gels that respond to mineralization and exhibit excellent characteristics such as small particle size, high dispersion, and strong stability by introducing catechol-like structures and temperature/salt-resistant functional monomers. Experimental results showed that the particle size of the dry dispersed gel particles ranged from tens to 100 nm, as observed by scanning electron microscopy. Laser particle size analyzer testing demonstrated that the size of the dispersed gel particles progressively increased with the mineralization degree of the dispersed particle gel, indicating a certain level of mineralization responsiveness. Additionally, these particles could maintain stable dispersion for up to 40 days in a solution with a mineralization degree of 20,000 mg/L. The rheology testing results indicate that the dispersed particle gels exhibited the properties of the pseudo-plastic fluid. Even under extreme conditions such as high temperature and mineralization, the strength of the dispersed particle gels remained intact, measuring 95.76 kPa after 40 days of aging. Using Materials Studio molecular simulation software, the stability and self-growth mechanism of dispersed gel particles were explained from the quantum mechanics perspective. The geometry of the dispersed gel particles was optimized using the Compass II force field, and the total energy of the model was calculated to be −757.579 kcal/mol, with the dihedral torsion energy contributing the most to the total energy. The molecular bond lengths in the polymer chain were then calculated, with the O–H bond being the shortest and the O-Na bond in the carboxylate sodium group being the longest. This indicated that the –OH group was more stable and the carboxylate sodium group was prone to hydrolysis, forming a –COOH group and increasing the dispersion stability. The charge distribution and molecular orbitals in the polymer molecule were also calculated, with the LUMO value being −7.405 eV and the HOMO value being −4.487 eV. This study used a reverse emulsion method to in-situ generate mineralization-responsive, multi-haired dispersed gel nanoparticles, which fundamentally solved the injection problem of low-permeability oil reservoirs and provided new materials for long-term plugging of high-temperature and high-salinity oil reservoirs.

Mixed Ionic-Electronic Conducting Hydrogels with Carboxylated Carbon Nanotubes for High Performance Wearable Thermoelectric Harvesters.

Mixed ionic-electronic conducting (MIEC) thermoelectric (TE) materials offer higher ionic conductivity and ionic Seebeck coefficient compared to those of purely ionic-conducting TE materials. These characteristics make them suitable for direct use in thermoelectric generators (TEGs) as the charge carriers can be effectively transported from one electrode to the other via the external circuit. In the present study, MIEC hydrogels are fabricated via the chemical cross-linking of polyacrylamide (PAAM) and polydopamine (PDA) to form a double network. In addition, electrically conducting carboxylated carbon nanotubes (CNT-COOH) are dispersed evenly within the hydrogel via sonication and interaction with the PDA. Moreover, the electrical properties of the hydrogel are further improved via the in situ polymerization of polyaniline (PANI). The presence of CNT-COOH facilitates the ionic conductivity and enhances the ionic Seebeck coefficient via ionic-electronic interactions between sodium ions and carboxyl groups on CNT-COOH, which can be observed in X-ray photoelectron spectroscopy results, thereby promoting the charge transport properties. As a result, the optimum device exhibits a remarkable ionic conductivity of 175.3 mS cm-1 and a high ionic Seebeck coefficient of 18.6 mV K-1, giving an ionic power factor (PFi) of 6.06 mW m-1 K-2 with a correspondingly impressive ionic figure of merit (ZTi) of 2.65. These values represent significant achievements within the field of gel-state organic TE materials. Finally, a wearable module is fabricated by embedding the PAAM/PDA/CNT-COOH/PANI hydrogel into a poly(dimethylsiloxane) mold. This configuration yields a high power density of 171.4 mW m-2, thus highlighting the considerable potential for manufacturing TEGs for wearable devices capable of harnessing waste heat.

Modification of TEMPO-oxidized cellulose nanofibers as a source of potassium and its impact on onion plant

This research study aims to improve the productivity and vegetative growth characteristics of onion to meet local demands and the volume of exports. This was done by the application of foliar nano-fertilizers based on cellulose nanofibers (CNF). TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) -oxidized cellulose nanofibers (TO-CNFs) were fabricated using the TEMPO-oxidized method in the presence of sodium or potassium hydroxide to obtain sodium carboxylate TO-CNFs (N-CNF) and potassium carboxylate TO-CNFs (K-CNF), respectively. Also, potassium acrylate was used in grafting N-CNF to get potassium polyacrylate-g-sodium carboxylate TO-CNFs (G-CNF). The prepared CNFs were described via various techniques such as FTIR, SEM, TGA, and XRD. X-ray analysis demonstrated that N-CNF, K-CNF, and G-CNF consisted of a crystalline domain of crystallinity index 0.45, 0.41, and 0.55, respectively. K-CNF showed marginally lower thermal stability than N-CNF influenced by its crystalline properties. The vegetative growth and the yield of onion plants, plus the content of photosynthetic pigments, minerals, cellulose, hemicellulose, and lignin, as well as total phenols, flavonoids, and indoles, were studied. The results showed that the application of K-CNF as a foliar nano-fertilizer improved the onion yield and the content of elements, protein, total soluble solid, phenols, and indoles as well as the content of cellulose and lignin

Thermal, morphology and bacterial analysis of pH-responsive sodium carboxyl methylcellulose/ fumaric acid/ acrylamide nanocomposite hydrogels: Synthesis and characterization

In this present investigation, sodium carboxymethyl cellulose grafted with Fumaric acid/Acrylamide (CMC/FA/AAm=CFA) hydrogel and their silver nanocomposite hydrogels (CFA-Ag x, x = 5, 10 and 20) were developed by simple, cost effective and ecofriendly greener method. Mint leaf extract was used as an efficient natural reducing agent due to presence of active and antioxidant potential of polyphenol and flavonoid components. Swelling equilibrium of CFA hydrogel showed Seq% 3000 both in pH medium and distilled water. CFA (90:10) hydrogel has been produced greater than Seq% 6000. The synthesized CFA (90:10)-Ag-5, CFA (90:10)-Ag-10 and CFA (90:10)-Ag-20 nanocomposite hydrogels have been observed lower Seq% 2000–3000 than the CFA hydrogel. The homogeneous distribution of AgNPs throughout the CFA hydrogel and nanocomposites has been explored by SEM analysis. The interaction of network heteroatoms with AgNPs has been strongly revealed by the FTIR spectra and XRD analysis. The thermal stability of CFA (90:10)-Ag-5, 10, and 20 nanocomposite hydrogels have showed greater stability than CFA hydrogel which is confirmed by TGA/DSC thermogram analysis. The TEM analysis was used to explore a uniform distribution of spherical AgNPs (10 nm–50 nm) embedded on the CFA composite hydrogel. The CFA (90:10)-Ag-20 nanocomposite hydrogel has showed good antibacterial activity beside E. coli (Gram positive) and S. aureus (Gram negative) pathogens. Based on the antibacterial activity and swelling properties of CFA-Ag nanocomposite hydrogels have the ability to accelerate the antibacterial activity and are potential candidates for medical and environmental applications.

Fabrication of efficient bipolar membranes with functionalized MOF interfacial layer for generation of various carboxylic acids via electrodialysis

Stability and compatibility of two layers with each other are the major drawback of the bipolar membrane (BPM). Sulfonated poly (ether ether ketone) and quaternized poly phenylene oxide are taken as the cation exchange layer (CEL) and anion exchange layer (AEL) respectively to fabricate the bipolar membrane by layer-by-layer assembly. Different functionalized MOF (MIL-101 Cr) are prepared for the interfacial layer (IL) of BPM as water dissociation (WD) catalysts. Various analytical techniques (XRD, FT-IR, SEM, BET, XPS, TGA) are used to examine the chemical structure, textural properties and thermal stability of the synthesized catalysts. Two different catalytic sites of MOF as inorganic metal-ion and organic ligands facilitates the water dissociation rate. The effect of different IL (functionalized MOF) on performance of BPM is studied for the dissociation of NaCl into corresponding acid and alkali. BPM with bi-functionalized MOF as IL (BPM-BMOF) shows the better electro-chemical and physicochemical properties in term of ionic conductivity (8.02 mS cm−1) with 38.1 % water uptake, among the synthesized BPMs. The performance of BPM-BMOF is evaluated for the generation of different organic carboxylic acids from sodium carboxylates using bipolar membrane electrodialysis (BPMED). BPM-BMOF shows the 94.12 % acid generation with 0.496 g h−1 water dissociation rate using 0.2 M NaCl feed solution. The results suggest that product recovery (PR) and energy efficiency (ƞ) gradually reduces with higher homologous of sodium carboxylates under similar experimental conditions. The performance of BPM-BMOF with negligible co-ion leakage and stability made it industrially applicable for water splitting.

High-energy storage capacity of cellulose nanofiber supercapacitors using bound water

The performance of electric double-layer capacitors and lithium-ion batteries deteriorates with increasing humidity. The desirable effect of bound water on the energy-storage properties of physically dry cellulose nanofiber (Na-ACF) supercapacitors with sodium (Na) carboxylate radicals was investigated using infrared and near-infrared spectroscopy, and nuclear magnetic resonance spectroscopy, alternating current impedance analyses, and first-principles calculations. The storage capacity decreased gradually upon heating to 423 K and reached zero upon exceeding 483 K, accompanied by increasing electrical resistance, forming a distorted semicircle in Nyquist diagram and drawing the phase angle to zero in Bode diagram. This is attributed to the water in the hydration gel bound to the Na+-ions that cross-link the cellulose chains, evaporating as the temperature increases, and finally becoming Na2O. The increased band-gap energy from the increase in bound water prevents leakage from the supercapacitor. In contrast to ordinary batteries, bound water is necessary for developing Na-ACF supercapacitors.