Biodegradable Polymer Electrolyte Research Articles

Exploring the potential of poly (caprolactone) and guar gum biodegradable blend film: an investigation for supercapacitor

A biodegradable polymer electrolyte comprising poly (caprolactone) (PCL) and guar gum (GG) doped with lithium perchlorate (LiClO4) was investigated for its application in supercapacitors. The films’ thermal properties, surface morphology, and tensile strength were determined to understand the interaction between the blend system and the salt. Scanning electron microscopic images showed a network of GG channels across the polymer matrix. A unique combo of THF/water as solvent was used for this study as they bring out relaxation in GG segments and compatibility between GG and PCL. The blend polymer electrolyte (BPE) was characterized using conductivity, dielectric, and biodegradation studies. Supercapacitors were fabricated, and electrochemical studies were performed. The optimized BPE was used to fabricate supercapacitors, producing a specific capacitance of 125 F g−1. The time constant was measured at 0.8 s, and a consistent cyclic pattern was observed during galvanostatic charge/discharge studies with 96% Coulombic efficiency. This novel amalgamation of polymeric films holds immense promise for supercapacitor applications.

Theoretical Study on the Electronic Structure of Polymer-in-Salt/Ionic Liquid-Based Biodegradable Gel Polymer Electrolyte

Theoretical Study on the Electronic Structure of Polymer-in-Salt/Ionic Liquid-Based Biodegradable Gel Polymer Electrolyte

The Effect of Sodium Acetate on Biodegradable Rice Starch-Based Solid Polymer Electrolyte for Supercapacitor

This study examined the use of sodium acetate salt as an ionic dopant in biodegradable solid polymer electrolyte (SPE). In the solution casting method for making polymer electrolyte, rice starch is used as the host polymer and glycerol is used as the plasticizer. The characteristics of SPE film were investigated using X-Ray Diffraction (XRD), Fourier Transform Infrared (FT-IR), and Thermogravimetric Analysis (TGA). Salt enhances the amorphous structure by decreasing the crystallinity of the polymer. Alternatively, it decreases the temperature of thermal breakdown. In addition, the biodegradability of SPE was investigated using the soil burial method. Electrochemical Impedance Spectroscopy (EIS) was used to evaluate the ionic conductivity behavior and temperature dependent of SPE. The 35% sodium acetate salt addition makes the supercapacitor's electrolyte have the highest ionic conductivity at room temperature, which is 5.57x10-4 S/cm.

Amorphous Magnesium-Doped Chitosan films as solid polymer electrolytes for energy storage device applications

Magnesium ion-conducting biodegradable solid polymer electrolyte (SPE) films of magnesium perchlorate [Mg(ClO4)2] doped Chitosan [CS] were prepared using the solution casting technique at room temperature. XRD study shows that amorphous nature of the polymer matrix increases upon doping. FTIR deconvolution confirm the complexation generated between the salt and the polymer. The current–voltage measurement exhibited electrochemical stability window for all samples above 2.14 V. The ionic transference number for the highest conducting sample was 0.99. The impedance analysis was done for each SPE film, and the sample with the highest concentration (40 wt%) exhibited the highest conductivity, 5.7 × 10-4 Scm−1. The prepared primary magnesium battery using the highest conducting SPE showed open circuit potential of 2.112 V. Due to its exceptional qualities, this prepared electrolyte may be a strong contender for energy storage systems.

Steps towards the ideal CV and GCD results with biodegradable polymer electrolytes: Plasticized MC based green electrolyte for EDLC application

Advanced materials are a primary focus of many research groups for applications in energy storage devices. Natural polymers, as a branch of advanced materials, are currently a hot topic to produce clean energy and reduce microplastics problems in the ocean and their potential harm to human health through ingestion. A novel biodegradable green polymer electrolyte was selected for energy storage in the current investigation. The MC polymer was impregnated with a fixed weight percent (40 %) of sodium thiocyanate (NaSCN) and different amount of glycerol to produce flexible films of solid polymer electrolytes (SPEs) using solution casting method. The XRD test reveals that the lowest degree of crystallinity is present in the most conductive electrolyte with increasing plasticizer. According to the electrochemical impedance spectroscopy (EIS) results, the sample that was incorporated with 50 % glycerol displayed the highest conductivity. FTIR was employed to observe the interaction of electrolyte components. Ions were found to be the primary species contributing to conduction, with transference numbers of 0.958 and 0.042 for ions (tion) and electrons (te), respectively. The results obtained from the linear sweep voltammetry (LSV) data confirm that the sample can withstand a voltage of approximately 2.54 V. This voltage level is suitable for extensive practical applications. The shape of the CV pattern was almost comparable to an ideal rectangular shape at low scan rates. A slight increase in the internal resistance (ESR) of the EDLC cell was observed, which increased from 59 to 68 Ω. The battery cycler was used to charge and discharge the designed EDLC device and some key parameters, including capacitance (110 F.g−1), energy density (15 Wh.Kg−1), and power density (1300 W.Kg−1) were determined from the discharge curve. Ultimately, based on the study of the assembled cell, it has been suggested that supercapacitors have emerged as potential alternative to replace environmentally harmful Li-ion batteries in advancing green energy.

Unleashing the potential of eco-friendly chitosan: Methylcellulose polyblend electrolytes via magnesium acetate doping for solid state batteries

The most popular choice for inexpensive and energy-efficient storage devices has been solid biodegradable polymer electrolyte systems. In this study, chitosan (CS), methylcellulose (MC), and magnesium acetate (Mg(CH3COO)2) salt were mixed to create magnesium ion conducting solid blend polymer electrolyte (SBPE) membranes. The X-ray diffraction (XRD) study exhibited a variation in microstructure due to the addition of Mg(CH3COO)2 salt to the poly-blend matrix, which was also confirmed by Fourier transform infrared (FTIR) spectroscopy. Electrochemical impedance analysis revealed the maximum ionic conductivity of 2.24 × 10−5 S cm−1 for the electrolyte film comprising 30 wt% of Mg(CH3COO)2. The ionic transference number (tion) of about 0.88 was observed for the same salt concentration, indicating the predominance of ions as charge carriers in the SBPE. Electrochemical analyses exhibited maximum electrochemical stability window (ESW) for the highest conducting sample, thus incorporating it as a separator-cum-electrolyte. The oxidation and reduction peaks are observed in the cyclic voltammetry curve of the highest conducting sample. The discharge characteristic profiles of electrochemical cells in the configuration Mg/(CS + MC + Mg(CH3COO)2)/cathode with three different types of cathode materials to explore the synergic effect between electrode and poly-blend electrolyte was studied.

High ionic conductivity upon low electrolyte uptake in TiO2 nanofiber-filled guar gum gel electrolytes

In nanocomposite gel polymer electrolytes (NCGPEs), high ionic conductivity is realized at a large electrolyte uptake ratio compromising the dimensional stability of the electrolyte films. The present work demonstrates interesting biodegradable gel polymer electrolytes based on guar gum (GG) dispersed with TiO2 nanofibers. Very high ionic conductivity of 2.3 × 10−3 Scm−1 at ambient temperature has been achieved at a relatively low electrolyte uptake ratio of 92% when nanofiber content in guar gum is 2.5 wt% ascertaining the role of nanofibers in promoting ion transport in NCGPEs. Nanofibers also empower the NCGPEs with higher electrochemical and interfacial properties making them a suitable candidate for energy storage systems of the next generation. The enhanced properties of NCGPEs induced by nanofibers have been supported by XRD, FTIR, XPS and computational studies.

An insight into the suitability of magnesium ion-conducting biodegradable methyl cellulose solid polymer electrolyte film in energy storage devices

Biodegradable solid polymer electrolyte films based on methyl cellulose and magnesium acetate tetrahydrate [Mg(CH3COO)2.4H2O] are prepared using the conventional solution casting technique. Structural analysis of the electrolyte films confirmed the complexation of salt with the polymer matrix. The incorporation of salt into the polymer matrix resulted in the enhancement of the amorphousness of the matrix. The thermal properties of the electrolyte film are analyzed with the help of DSC and TGA thermograms. Impedance analysis of the films indicates the enhancement of the electrical conductivity of the system. The maximum room temperature ionic conductivity (2.61 × 10−5 S/cm) was observed for the 25wt% salt-doped sample. The highest conducting electrolyte system has an Electrochemical Stability Window (ESW) of 3.47 V. In the current work, a primary battery was assembled using the highest conducting polymer electrolyte system, and its open-circuit potential and discharge characteristics were also investigated.Graphical abstract

Investigations on anomalous behavior of ionic conductivity in NaPF6 salt loaded hydroxyethyl cellulose biodegradable polymer electrolyte for energy storage applications

AbstractThis article investigates the influence of NaPF6 salt content (0–30 wt.% in a varying interval of 5 wt.%) on the structural, electrical, and biodegradable properties of HEC/NaPF6 solid biopolymer electrolyte (SBE) films. The interaction of salt with the HEC polymer matrix is confirmed by FTIR and SEM studies. The elemental composition and mapping confirm the appearance of NaPF6 moieties in the HEC polymer matrix. XRD deconvolution reveals that HEC samples with 20 wt.% (H4) and 10 wt.% of salt (H2) have a significantly lower crystallinity index than pure HEC polymer. The H2 and H4 samples show the highest room temperature conductivity values (1.62 × 10−5 and 1.13 × 10−5 S cm−1, respectively) among all other prepared samples since carrier concentration influences the ionic conductivity and shares a similar order of conductivity. Thus, the H2 and H4 samples are employed as electrolyte separators in the sodium ion battery, and the results suggest that the H2‐based electrolyte system is more significant. Battery matrices like open circuit voltage (V), current density (μA cm−2), power density (mW kg−1), energy density (Wh kg−1) and discharge capacity (μA h−1) were calculated and found to be 2.48, 5.49, 44.60, 1.69, and 71.05, respectively for H2 electrolyte based cell. Wagner polarization reveals that H2 and H4 constitute the predominant charge carriers (ions) with total ion transference numbers of ⁓0.98 and ⁓0.99, respectively. To evaluate sample degradability, H2 and H4 samples were subjected to 20 and 5‐day biodegradation processes, during which the polymers completely (100%) broke down.

Structural, thermal, and electrochemical studies of biodegradable gel polymer electrolyte for electric double layer capacitor

A quasi-solid-state supercapacitor is fabricated using a biodegradable gel polymer electrolyte (GPE), and graphene nano-platelets (GNPs) capacitive electrodes. The GPE film comprises biodegradable polymer cellulose acetate (CA), ionic liquid, 1-ethyl-3-methylimidazolium thiocyanate (EMImSCN) and dopant salt potassium thiocyanate (KSCN). The polymeric gel films are prepared using the standard “solution cast technique” and characterized by using X-ray diffraction (XRD), Differential scanning calorimetry (DSC), Thermogravemetric analysis (TGA), Impedance spectroscopy, and Linear sweep voltammetry techniques. The synthesized GPE exhibits maximum room temperature ionic conductivity ∼1.2 x 10−3 S cm−1 and an electrochemical stability window of ∼2.4 V. The electrical double layer capacitor (EDLC) is configured by sandwiching the GPE film between two graphene nanoplatelets (GNPs) electrodes. The performance of the EDLC cell is evaluated in terms of specific capacitance, rate, and pulse power by using cyclic voltammetry, and electrochemical impedance measurement techniques.

Structural and energy storage behavior of ion conducting biopolymer blend electrolytes based on methylcellulose: Dextran polymers

Biodegradable polymer electrolyte has attracted significant attention from both economic and environmental perspectives. This study reports the preparation and analysis of plasticized methylcellulose (MC)-dextran (DN)-ammonium iodide (NH4I) bio-based polymer electrolytes with high ion transport properties using solution casting method.It was discovered that when the glycerol concentrations increased, the FTIR bands changed and dropped in their intensities, revealing good complexation between electrolyte constituents. The glycerol inclusion improved the ionic conductivity up to (3.24 × 10−4) S/cm, according to impedance spectroscopy (EIS). The EEC simulation has been employed to study the electrolyte circuit components further. Transference number measurement (TNM) was used to calculate both transport ion (tion) and electron (tel) values, which were found to be 0.952 and 0.048, respectively. The most conducting sample was found to be stable up to 2 V. Various techniques, such as cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) were utilized to examine the properties of the assembled EDLC device. At the initial cycle, the designed EDLC had a specific capacitance (Cspe) value of ∼ 44F/g, with an energy density of ∼ 4.9 Wh/kg and a power density of ∼ 500 W/kg.

UTILIZATION AND MODIFICATION OF PINEAPPLE SKIN WASTE FOR POLYMER ELECTROLYTE MEMBRANE APPLICATION

The latest fuel cell development uses biodegradable polymer electrolyte membranes (PEM) to separate the cathode and anode components, making it an exciting research topic. This research develops a cheap and eco-friendly polymer electrolyte membrane (PEM) material. The membrane material is pineapple peel waste, which is easily biodegradable and naturally abundant. Sulfonate groups were added together with varied sulfuric acid concentrations to modify it. The membrane was then evaluated for its mechanical strength, proton conductivity, swelling index, and ion exchange capacity (IEC). In addition, this study performed morphological, sulfur content, and functional group analyses using FTIR, SEM, and EDS. In accordance with the findings, the best nata de pina membrane had a proton conductivity of 1.85 x 10-2 S/cm, an IEC of 3.85 mEq/g, a degree and swelling of 118.55%, and was sulfonated with 1.08 N sulfuric acids. Additionally, the resulting membrane’s mechanical strength increased significantly. Therefore, pineapple peel is an environmentally friendly natural resource useful in manufacturing electrolyte membranes.

Design of non-faradaic EDLC from plasticized MC based polymer electrolyte with an energy density close to lead-acid batteries

The investigation of biodegradable polymer electrolyte for energy device applications is of great importance as a suitable alternative to the conventional electrolytes. This paper explores the employment of plasticized methylcellulose (MC)-based polymer electrolytes for energy storage EDLC device application with an energy density (46.29 Wh kg−1) close enough to lead-acid batteries. The results have shown that the inclusion of plasticizer can enhance the ionic conductivity to 1.17 × 10−3 S cm−1. It was found that the prepared polymer electrolyte was stable up to 2.1 V, which is sufficient to be employed as electrolyte and separator in fabrication of electrical double layer capacitor (EDLC). Both te and ti values have been quantified from the TNM measurements, where the ti values for the electrolytes containing 32 wt.% and 40 wt.% of glycerol plasticizer have been found as 0.963 and 0.802, respectively. The performance of the assembled EDLC was assessed using both cyclic voltammetry (CV) and charge-discharging responses. The absence of redox peaks is evidenced from the CV. The value of initial specific capacitance (Cspe) of the fabricated EDLC is 411.52 F g−1. The results achieved in this study can be considered as a breakthrough in EDLC devices.

A phosphorylated nanocellulose/hydroxypropyl methylcellulose composite matrix: A biodegradable, flame-retardant and self-standing gel polymer electrolyte towards eco-friendly and high safety lithium ion batteries

Gel polymer electrolyte (GPE) is considered as a midway solution of liquid electrolyte and solid polymer electrolyte. Nowadays, the biodegradable and renewable cellulose based GPEs are adopted as promising substitutes for GPEs based on other polymers like PVDF and PMMA. However, the safety concerns derived from the flammability of cellulose still hinders the practical application of the cellulose based GPEs. Simultaneously, the conventional methods to improve the flame-resistance of the host membranes are either unreliable or often invalidate the biodegradability of the GPEs based on cellulose. To achieve the unique combination of biodegradability and high safety, we report the preparation of composite GPEs with flame-retardancy resulted from hydrolysis between phosphorylated nanocellulose (PNC) and hydroxypropyl methylcellulose (HPMC). Besides, the present GPEs are demonstrated to be self-standing and mechanically robust with the advent of PNC. In comparison of the GPEs with various content of PNC, MPC50%/GPC50% are considered as the suitable options thanks to the high tensile strength, satisfactory electrochemical performances and good flame-retardancy. Finally, the LiFePO4/GPC50%/Li coin battery performs a remarkable cycling performance with a high capacity retention of 88.9% at 0.2C and a good rate capability in the battery test. It is anticipated that the as-constructed GPE can contribute to the design on the eco-friendly and high safety batteries in the future.

Synthesis and characterization of Dextran, poly (vinyl alcohol) blend biopolymer electrolytes with NH4NO3, for electrochemical applications

ABSTRACT New biocompatible biopolymer membranes have been synthesized from naturally occurring bacterial polysaccharide Dextran, which is efficacious versatile polymer known for medicinal applications. In the present study, biodegradable solid polymer electrolytes based on Dextran:Poly vinyl alcohol (PVA) with different composition of ammonium nitrate (NH4NO3) are prepared by solution casting technique with double distilled water as a solvent. The prepared polymer membranes have been characterized by various techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetric (DSC), AC impedance, linear sweep voltammetry (LSV), and transference number measurement. The amorphous nature of the polymer membrane is enhanced due to the addition of ammonium nitrate has been confirmed by X-ray diffraction analysis. The complex formation between the host polymer and the salt has been studied by Fourier transform infrared spectroscopy. The highest ionic conductivity of 1.66 × 10−3 S/cm for the composition 700 mgDextran:300 mgPVA:450 mgNH4NO3 has been observed by AC impedance spectroscopy at room temperature. The electrochemical stability of the highest conducting polymer electrolyte (700 mgDextran:300 mgPVA:450 mgNH4NO3) has been observed as 3.32 V by Linear sweep voltammetry. From Wagner’s polarization method transference number of highest conducting polymer electrolyte has been calculated as 0.99. Finally primary proton battery has been constructed using the highest conducting polymer membrane of 700 mgDextran:300 mgPVA:450 mgNH4NO3. Its open circuit voltage is measured as 1.51 V and its performance is studied.

Characterization of Solid Polymer Electrolyte Based on Methylcellulose Doped Ammonium Bromide

A new biodegradable and low cost solid polymer electrolyte (SPE) membrane mainly from Methylcellulose (MC) blended with Ammonium Bromide (AB) to enhance the SPEs ionic conductivity. Casting method was used in this study in order to produce thin film. In this study, MC as a based doped with different weight percentage of AB (4%, 9%, 14%, 19%, 24% and 29%) to produce thin film for further study on polymer electrolytes. Two objectives were done in this study: prepare MC doped AB thin film via casting method and to determine and compare the conductivity of MC and AB with different weight percentage (wt.%) of AB. The result shows that different weight percentage of salt resulting different result of conductivities as ion conductivities is the major part in the battery system. Sample MCAB19 was found to have the maximum ionic conductivity value of 1.42 x 10−7Scm−1 at room temperature. The samples’ conductivity is very low comparing to the commercial used nowadays. However, it is proven that the combination of MC and AB has the prospective to be an alternative to a SPE in the battery.

Resorcinol-Formaldehyde (RF) as a Novel Plasticizer for Starch-Based Solid Biopolymer Electrolyte.

A starch-resorcinol-formaldehyde (RF)-lithium triflate (LiTf) based biodegradable polymer electrolyte membrane was synthesized via the solution casting technique. The formation of RF crosslinks in the starch matrix was found to repress the starch’s crystallinity as indicated by the XRD data. Incorporation of the RF plasticizer improved the conductivity greatly, with the highest room-temperature conductivity recorded being 4.29 × 10−4 S cm−1 achieved by the starch:LiTf:RF (20 wt.%:20 wt.%:60 wt.%) composition. The enhancement in ionic conductivity was an implication of the increase in the polymeric amorphous region concurrent with the suppression of the starch’s crystallinity. Chemical complexation between the plasticizer, starch, and lithium salt components in the electrolyte was confirmed by FTIR spectra.

Development of polymer electrolyte membranes based on biodegradable polymer

Over the use of conventional liquid electrolytes, polymer based electrolytes have paid a special attention in the area of energy research mainly because of their flexibility and ease of availability. From the last few decades, non-degradable and synthetic polymers had been used as host polymers for the development of highly ionic conducting polymer electrolytes. From our earlier studies, different polymer electrolytes based on synthetic polymer such as polyethylene oxide (PEO) have also been studied with obtained conductivity values of the order of 10−7-10−4 S/cm. Three orders of increase in conductivity has been observed with the addition of additives such as plasticizer as well as nano filler and some of the data is represented in this paper. But in the present scenario, use of biodegradable polymer electrolytes is highly preferable over non-degradable polymer electrolytes because of their renewability and biocompatibility. Also, the use of blend and additives in the polymer electrolytes have become the most promising ways to improve the ion transport as well as electrochemical performance of polymer electrolytes. Polymer electrolytes based on specially the biodegradable polymer have been addressed to bring one step ahead to show the enhanced ionic conductivity, mechanical stability and improved interfacial stability towards electrode materials. Present paper highlights a review on the recent research efforts dedicated by researchers to understand the ion conduction mechanism in the modified polymer electrolytes as well as the usefulness of the biodegradable Polycaprolactone (PCL) as a host polymer in different polymer electrolytes.

Characterization of Solid Polymer Electrolyte Membrane made of Methylcellulose and Ammonium Nitrate

Nowadays, the application of portable electronics devices such as smartphone, notebook and tablet playing important role in daily life. This portable electronic devices required portable powering sources such as battery. However, the current battery technology containing liquid electrolyte which is hazardous and harmful when leaking. Therefore, the major purpose of this study was to propose a new biodegradable, safe and low cost solid polymer electrolyte (SPEs) mainly from Methylcellulose (MC) doped Ammonium Nitrate (AN). The study was conducted by using casting method as it is the most appropriate technique due to its simplicity and low cost. Methylcellulose (MC) as the host was doped with different weight percentage (wt%)of Ammonium Nitrate (AN) to fabricate SPEs. The result shows the adding of AN onto MC was significantly enhanced the physical properties of SPEs. The loading of 2g MC with 25% AN (MC2_25AN) yield the highest conductivity at 3.5 × 10−7 Sm−1 at room temperature. Furthermore, the MC2_25AN poses a good stability with the lowest swelling rate. Therefore, the use of low cost and biodegradable MC and AN have a great potential to replace the hazardous electrolyte in electrochemical powering sources.

Characterization of biodegradable solid polymer electrolyte system based on agar-NH4Br and its comparison with NH4I

Concerning the pollution-free and eco-friendly materials, the prospect of using biopolymer as ion conducting matrix has been investigated in this study. Biopolymer electrolyte based on agar with different concentrations of NH4Br has been prepared by solution casting technique using water as solvent. The prepared electrolytes are characterized by X-ray diffraction analysis, Fourier-transform infrared spectroscopy, AC impedance spectroscopy, and electrochemical stability. X-ray diffraction is done to study the nature (amorphous/crystalline) of the polymer membranes. The complexation of the prepared polymer electrolytes has been studied using Fourier-transform infrared (FTIR) spectroscopy. The maximum ionic conductivity of 1.33 × 10−4 S cm−1 has been obtained for 50 M.wt% NH4Br with agar polymer electrolyte. The temperature dependence of ionic conductivity of the prepared polymer electrolytes obeys Arrhenius law. The ionic transference numbers of mobile ions have been estimated by Wagner’s dc polarization method and the results reveal that the conducting species are predominantly ions. The electrochemical stability is studied by linear sweep voltammetry. A battery has been constructed using the highest conductivity sample and its output voltage is found to be 1.80 V. A proton-exchange membrane fuel cell fabricated with the 50 M.wt% NH4Br-doped agar polymer electrolyte exhibited an output voltage of 500 mV. These results of 50 M.wt% NH4Br-doped agar have been compared with 50 M.wt% agar:50 M.wt% NH4I biopolymer electrolyte.