Enhancing proton conductivity of sodium alginate doped with glycolic acid in bio-based polymer electrolytes system

Synergistic Blends of Sodium Alginate and Pectin Biopolymer Hosts as Conducting Electrolytes for Electrochemical Applications

The world needs sustainable energy resources with affordable, economic, and accountable sources. Consequently, energy innovation technologies are evolving toward electrochemical applications like batteries, supercapacitors, etc. The current study involves the solid blend biopolymer electrolyte (SBBE) with different compositions of sodium alginate blended with pectin via the casting technique. The characterization of the sample was tested by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, AC impedance, linear sweep voltammetry (LSV), and cyclic voltammetry (CV) analyses. Evidently, the sample NP4 (NaAlg/pectin = 60:40 wt %) has a higher conductivity of 1.26 × 10-7 and 3.25 × 10-6 S cm-1 at 303 and 353 K, respectively. The performances of the samples were analyzed with variations in temperature, frequency, and time responses to signify the blended nature of the electrolyte. Hence, the studied biopolymers can be constructed for electrochemical device applications.

Studies on the effect of H+ carrier toward ionic conduction properties in alginate-ammonium sulfate complexes–based polymer electrolytes system

The present work highlights the contribution of ammonium sulfate (NH4)2SO4 as H+ carriers in alginate-based solid polymer electrolytes (SPEs) that were successfully prepared via a solution casting technique. The Fourier transform infrared analysis revealed that molecular interactions between the host polymer and the ionic dopant complexes occurred at the wavenumbers 3700–2500 cm−1, 1800–1500 cm−1, and 1200–900 cm−1. These regions corresponded to the O-H stretching, COO− and C-O-C, moieties of alginate, respectively, which coordinated with the H+ carrier from (NH4)2SO4. At ambient temperature, the optimum ionic conductivity was obtained at 3.01 × 10−5 S cm−1 for the sample containing 10 wt.% of (NH4)2SO4. The IR-deconvolution approach shows that the ionic conduction enhancement is governed by the ionic mobility and the diffusion coefficient of H+ carriers, and the findings show that the present biopolymer, which is an alginate-based SPEs system, has an excellent possibility to be used as electrolytes for application in electrochemical devices.

Nanofibrillated Cellulose-Based Aerogels Functionalized with Tajuva (Maclura tinctoria) Heartwood Extract

Aerogels are 3-D nanostructures of non-fluid colloidal interconnected porous networks consisting of loosely packed bonded particles that are expanded throughout their volume by gas and exhibit ultra-low density and high specific surface area. Cellulose-based aerogels can be obtained from hydrogels through a drying process, replacing the solvent (water) with air and keeping the pristine three-dimensional arrangement. In this work, hybrid cellulose-based aerogels were produced and their potential for use as dressings was assessed. Nanofibrilated cellulose (NFC) hydrogels were produced by a co-grinding process in a stone micronizer using a kraft cellulosic pulp and a phenolic extract from Maclura tinctoria (Tajuva) heartwood. NFC-based aerogels were produced by freeze followed by lyophilization, in a way that the Tajuva extract acted as a functionalizing agent. The obtained aerogels showed high porosity (ranging from 97% to 99%) and low density (ranging from 0.025 to 0.040 g·cm^-3), as well a typical network and sheet-like structure with 100 to 300 μm pores, which yielded compressive strengths ranging from 60 to 340 kPa. The reached antibacterial and antioxidant activities, percentage of inhibitions and water uptakes suggest that the aerogels can be used as fluid absorbers. Additionally, the immobilization of the Tajuva extract indicates the potential for dentistry applications.