Structural and Ionic Transport Study on CMC Doped NH4Br: A New Types of Biopolymer Electrolytes

Structural, Optical and Antibacterial Activity Studies on CMC/PVA Blend Filled with Three Different Types of Green Synthesized ZnO Nanoparticles

In this work, zinc oxide (ZnO) was produced using extracts of Thymus (Z), Hibiscus rosa-sinensis (K), and Daucus carota (G). Furthermore, sodium carboxymethyl cellulose (CMC) and polyvinyl alcohol (PVA) were combined with ZnO to form three novel nanocomposites. X-ray diffraction (XRD) was used for the structural analysis, where the semicrystalline nature of the (CMC/PVA)/ZnO nanocomposites was confirmed. The characteristics functional groups that arose inside the prepared samples were identified by Fourier transform infrared spectroscopy (FTIR). Evidence for the successful preparation of the pure ZnO particles and their nanocomposites was carried out using a transmission electron microscope (TEM). The ZnO nanoparticles are mostly spherical, irregularly distributed, and have radii ranging from 10 to 40 nm. Their anti-bacterial activity was studied against B. subtilis, E. coli, and Candida albicans. The inhibition zones of all the prepared samples against E. coli were 0, 19, 31, and 23 mm for PVA/CMC blend, PVA/CMC/ZnO (Z) (PCZ-Z), PVA/CMC/ZnO (K) (PCZ-K), and PVA/CMC/ZnO (G) (PCZ-G), respectively, compared to the streptomycin control Gram-positive standard with inhibition zone (34 mm). On the other hand, the inhibition zones of the prepared samples against B. subtilis were equal to 0, 26, 33, and 28 mm for CMC/PVA, PCZ-Z, PCZ-K, and PCZ-G, respectively. Based on these results, the PCZ-K sample is the most effective at resisting E. coli (91.17%) and B. subtilis (94.28%). These nanocomposites do not have harmful chemicals, making them strong candidates for use in biological applications.

Proton-Conducting Biopolymer Electrolytes Based on Carboxymethyl Cellulose Doped with Ammonium Formate

In this work, CMC-AFT biopolymer electrolytes system was developed using Carboxymethyl cellulose (CMC) doped with varied amount (10-50 wt.%) of ammonium formate (AFT) in order to study the effect of AFT on the biopolymer-salt system. The chemical structure of the biopolymer was studied using Fourier-Transform infrared (FTIR) and X-ray diffraction (XRD). The interaction between the COO^- of CMC and the weakly-bound H⁺ of NH₄⁺ AFT occurred at 1573 cm^-1 as seen in FTIR analysis and the amorphous phase was found to increase with the addition of AFT as seen from XRD pattern. Both FTIR and XRD testing indicates that the AFT had disrupted the CMC crystalline structure. The ionic conductivity of the CMC-AFT biopolymer electrolytes increases and achieved the highest value of 1.47 × 10^-4 S·cm^-1 with the addition of AFT. The impedance measurement showed that the capacitive and resistive behavior inside the biopolymer diminished when 50 wt.% of AFT was added. Dielectric analysis confirmed the increased number of charge carriers is due to the increase in AFT composition. Further dielectric analysis showed the occurrence of conductivity relaxation peak thus affirmed the charge carriers' ability to travel further to a longer distances when AFT composition increases from 10 to 50 wt.%. The dielectric properties confirmed the non-Debye behavior of the CMC-AFT biopolymer electrolytes.

High Cyclability Energy Storage Device with Optimized Hydroxyethyl Cellulose-Dextran-Based Polymer Electrolytes: Structural, Electrical and Electrochemical Investigations

The preparation of a dextran (Dex)-hydroxyethyl cellulose (HEC) blend impregnated with ammonium bromide (NH₄Br) is done via the solution cast method. The phases due to crystalline and amorphous regions were separated and used to estimate the degree of crystallinity. The most amorphous blend was discovered to be a blend of 40 wt% Dex and 60 wt% HEC. This polymer blend serves as the channel for ions to be conducted and electrodes separator. The conductivity has been optimized at (1.47 ± 0.12) × 10⁻⁴ S cm⁻¹ with 20 wt% NH₄Br. The EIS plots were fitted with EEC circuits. The DC conductivity against 1000/T follows the Arrhenius model. The highest conducting electrolyte possesses an ionic number density and mobility of 1.58 × 10²¹ cm⁻³ and 6.27 × 10⁻⁷ V⁻¹s⁻¹ cm², respectively. The TNM and LSV investigations were carried out on the highest conducting system. A non-Faradic behavior was predicted from the CV pattern. The fabricated electrical double layer capacitor (EDLC) achieved 8000 cycles, with a specific capacitance, internal resistance, energy density, and power density of 31.7 F g⁻¹, 80 Ω, 3.18 Wh kg⁻¹, and 922.22 W kg⁻¹, respectively.

Effects of Ultrasonication Time on the Properties of Polyvinyl Alcohol/Sodium Carboxymethyl Cellulose/Nano-ZnO/Multilayer Graphene Nanoplatelet Composite Films

Ultrasonication-assisted solution casting was used to prepare polyvinyl alcohol (PVA)/sodium carboxymethyl cellulose (CMC)/nano-ZnO/multilayer graphene nanoplatelet (xGnP) composite films; the performances (mechanical properties, water vapor permeability (WVP), biodegradability and antibacterial activity) of these films were investigated as a function of the ZnO NPs:xGnP mass ratio and ultrasonication time. Intermolecular interactions among ZnO NPs, xGnP and the PVA/CMC matrix were shown to improve WVP, while X-ray diffraction and scanning electron microscopy analyses revealed that the internal reticular structure of ultrasound-treated PVA/CMC/ZnO NPs/xGnP composite films was in a fluffier state than that of the untreated composite films and the PVA/CMC film. The incorporation of ZnO NPs and xGnP into the composite film reduced its tensile strength and elongation at break, and increased antibacterial activity and biodegradability. In addition, we carried out the experiment of strawberry preservation and measured weight loss ratio, firmness, content of total soluble solids and titration acid. Finally, the composite film of 7:3 had the best preservation effect on strawberries. Thus, the obtained results paved the way to develop novel biodegradable composite films with antimicrobial activity for a wide range of applications.

Properties enhancement of carboxymethyl cellulose with thermo-responsive polymer as solid polymer electrolyte for zinc ion battery

A novel polymer host from carboxymethyl cellulose (CMC)/poly(N-isopropylacrylamide) (PNiPAM) was developed for a high safety solid polymer electrolyte (SPE) in a zinc ion battery. Effects of the PNiPAM loading level in the range of 0-40% by weight ( wt%) on the chemical, mechanical, thermal, and morphological properties of the CMC/PNiPAMx films (where x is the wt% of PNiPAM) were symmetrically investigated. The obtained CMC/PNiPAMx films showed a high compatibility between the polymers. The CMC/PNiPAM20 blend showed the greatest tensile strength and modulus at 37.9 MPa and 2.1 GPa, respectively. Moreover, the thermal degradation of CMC was retarded by the addition of PNiPAM. Scanning electron microscopy images of CMC/PNiPAM20 revealed a porous structure that likely supported Zn2+ movement in the SPEs containing zinc triflate, resulting in the high Zn2+ ion transference number (0.56) and ionic conductivity (1.68 × 10-4 S cm-1). Interestingly, the presence of PNiPAM in the CMC/PNiPAMx blends showed a greater stability during charge-discharge cyclic tests, indicating the ability of PNiPAM to suppress dendrite formation from causing a short circuit. The developed CMC/PNiPAM20 based SPE is a promising material for high ionic conductivity and stability in a Zn ion battery.

Structural and Ionic Conductivity Studies of CMC Based Polymerelectrolyte Doped with NH4Cl

The present study aims to investigate the structural and ionic conductivity of carboxymethyl cellulose - ammonium chloride as proton conducting polymer electrolytes. The complexion of polymer electrolyte films has been confirmed via FTIR studies. The conductivity enhancement with the addition of ammonium chloride concentration was proved due to the increase in amorphous nature of the films as evidenced by XRD analysis. Impedance studies indicate that the highest ionic conductivity of 1.43 x 10-3 Scm-1 was observed with the addition of 16 wt.% ammonium chloride in polymer electrolyte system obtained at ambient temperature.

Conductivity and Dielectric Analysis of Cellulose Based Solid Polymer Electrolytes Doped with Ammonium Carbonate (NH4CO3)

The present work investigated the effect of carboxy methylcellulose (CMC) solid polymer electrolytes doped with ammonium carbonate (AC) prepared from solution cast technique. The CMC-AC solid polymer electrolytes system has been analyzed using EIS to understand its conductivity and dielectric behavior at temperature range of 303 K to 363 K. The highest conductivity achieved at room temperature (303K) is 7.71 x 10-6S cm-1doped with 7wt.% of AC and all samples follows Arrhenius behaviour. The dielectric constant (εr) value was found to be dependent of ionic dopant.

Conductivity and Transport Properties Study of Plasticized Carboxymethyl Cellulose (CMC) Based Solid Biopolymer Electrolytes (SBE)

Solid biopolymer electrolytes (SBE) comprising carboxymethyl cellulose (CMC) with NH4Br-EC were prepared by solution casting method. The samples were characterized by impedance spectroscopy (EIS) and sample containing 25wt. % of NH4Br exhibited the highest room temperature conductivity of 1.12 x 10-4S/cm for salted CMC based SBE system. The ionic conductivity increased to 3.31 x 10-3S/cm when 8 wt. % of ethylene carbonate (EC) was added to the highest conductivity. The conductivity-temperature of plasticized SBE system obeys the Arrhenius relation where the ionic conductivity increases with temperature. The influence of EC addition on unplasticized CMC based SBE was found to be dependent on the number and the mobility of the ions. This results revealed that the influence of plasticizer (EC) which was confirmed play the significant role in enhancement of ionic conductivity for SBE system.