Review on Microstructural and Ion‐conductivity Properties of Biodegradable Starch‐Based Solid Polymer Electrolyte Membranes

Abstract

Currently, scientific developments in both the academic and industrial research communities are giving much attention towards the development of green chemistry secondary ion batteries with safety attributes. Biodegradable starch polymer-based electrolyte systems doped with different inorganic salts are gaining much attention owing to their intriguing and non-toxic nature. In this context, several research approaches have been identified for the improvement of lithium-ion conductivities at ambient temperatures, thermal and mechanical properties of starch polymer-based electrolytes. The present review provides consolidated information on chronological developments in the fabrication of different types of starch-based electrolytes (i.e., pure, blend, plasticized, and nanocomposites) and discusses microstructural, thermal, mechanical, and lithium-ion conductivity properties given lithium-ion batteries. Among all types, ionic liquids doped starch-based electrolytes demonstrated appreciable room temperature Li-ion conductivities. In parallel, a comparative study on Na + , K + , NH 4 + , Ag + , and Mg 2+ -ions conductivities in starch-based electrolytes is presented to emphasize the further research scope on the development of novel secondary ion batteries in complementing with lithium-ion batteries.

Effect of Lithium Salts on the Properties of Cassava Starch Solid Biopolymer Electrolytes

“…Consequently, the interactions between the ions of the dissociated salt and the biopolymeric molecules are of great importance. The possible interactions and effects of the type of salt used in the preparation of SBPEs can be evidenced using infrared spectroscopy [29][30][31]. Figure 1a shows the FTIR spectrum obtained from SBPE-FS films, where the characteristic bands of starch reported in the literature are observed [32,33].…”

“…Oxygen atoms can act as electron donors, so the vibrations related to these atoms revert greater interest in this study. The free electrons of the oxygen atoms can form dative bonds with the lithium ions from the added salts, so biopolymer-Li complexes could be formed [30,31].…”

“…Li + cations can interact with the oxygen atoms of glucose units in the biopolymer chain of starch to form biopolymer-Li complexes through the coordination of biopolymer oxygen atoms and the Li + cation, which affect molecular packaging and therefore affect its crystallinity. Additionally, the anionic component of the salts, without a doubt, can also affect the biopolymeric structure and its properties because it can generate molecular interactions or/and hydrogen bonds with the protons of the hydroxyl groups in the glucose units or the plasticizers [30,36]. These interactions can occur because the oxygen atoms in the sulfate anions (SO 2− 4 and CF 3 SO − 3 ) can easily interact with the hydrogen atoms of the OH groups present in the biopolymeric matrix (starch and plasticizers).…”

Modification in the microstructure of sodium carboxymethylcellulose/polyvinyl alcohol polyblend films through the incorporation ofNaNO3for energy storage applications

“…This is advantageous because it is available at a low cost and is eco‐friendly. Polysaccharides such as cellulose, starch, pectin, gums, and so on are the most abundant biodegradable polymers where the monomers are connected by glycosidic linkage 6 . In this regard, carboxymethyl cellulose (CMC) has been selected as the host polymer in this work to prepare the polymer electrolytes due to its remarkable ability to form film, good mechanical strength, and more importantly, is biodegradable and biocompatible.…”

“…Polysaccharides such as cellulose, starch, pectin, gums, and so on are the most abundant biodegradable polymers where the monomers are connected by glycosidic linkage. 6 In this regard, carboxymethyl cellulose (CMC) has been selected as the host polymer in this work to prepare the polymer electrolytes due to its remarkable ability to form film, good mechanical strength, and more importantly, is biodegradable and biocompatible. The CMC has several COO À and -OH functional groups in which the free ion dissociated from the ionic salts can interact, thereby serving as "multipoint interaction" centers.…”