In this work, solid flexible polymer blend electrolytes (PBE) composed of polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) with different amounts of sodium thiocyanate (NaSCN) salt mixed in double-distilled water (solvent) are prepared via solution casting method. The obtained films are characterized using several techniques. The study of the surface morphology of the polymer blend salt complex films via the POM technique reveals the presence of amorphous regions due to the NaSCN effect. FTIR spectra studies confirm the complex formation between PVA, PVP, and NaSCN. The addition of 20 wt% NaSCN salt in the composition PVA: PVP (50:50 wt%) polymer blend matrix leads to an increase in the number of charge carriers and thus improves the ionic conductivity. The ionic conductivity of each polymer blend electrolyte was studied using the electrochemical impedance spectroscopy (EIS) method. The highest room temperature ionic conductivity of 8.1 × 10⁻⁵ S/cm S cm⁻¹ is obtained for the composition of PVA: PVP (50:50 wt%) with 20 wt% NaSCN. LSV test shows the optimized ion-conducting polymer blend electrolyte is electrochemically stable up to 1.5 V. TNM analysis reveals that 99% of ions contribute for the conductivity against 1% of electrons only in the highly conductive polymer electrolyte PVA: PVP (50:50 wt%) + 20 wt% NaSCN. A supercapacitor device was fabricated using the optimized ion-conducting polymer blend film and graphene oxide (GO) coated electrodes. The GCD curve clearly reveals the behavior of an ideal capacitor with less Faradic process and low ESR value. The columbic efficiency of the GO-based system is found to be 100%, the GO-based electrode exhibits a specific capacitance of 12.15 F/g and the system delivers the charge for a long duration. The specific capacitance of the solid-state supercapacitor cell was found to be 13.28 F/g via the CV approach close to 14.25 F/g obtained with EIS data at low frequency.

In recent decades, the enhancement of the properties of electrolytes and electrodes resulted in the development of efficient electrochemical energy storage devices. We herein reported the impact of the different polymer electrolytes in terms of physicochemical, thermal, electrical, and mechanical properties of lithium-ion batteries (LIBs). Since LIBs use many groups of electrolytes, such as liquid electrolytes, quasi-solid electrolytes, and solid electrolytes, the efficiency of the full device relies on the type of electrolyte used. A good electrolyte is the one that, when used in Li-ion batteries, exhibits high Li+ diffusion between electrodes, the lowest resistance during cycling at the interfaces, a high capacity of retention, a very good cycle-life, high thermal stability, high specific capacitance, and high energy density. The impact of various polymer electrolytes and their components has been reported in this work, which helps to understand their effect on battery performance. Although, single-electrolyte material cannot be sufficient to fulfill the requirements of a good LIB. This review is aimed to lead toward an appropriate choice of polymer electrolyte for LIBs.

The demanding need for sustainable energy solutions has driven notable progress in solar cell technology, with perovskite solar cells (PSCs) emerging as a promising option. This research introduces a novel method to boost PSC efficiency by incorporating a double perovskite active layer (DPAL) design featuring CsSnGeI ₃ and CsSnI ₃ having energy bandgap of 1.5 and 1.3 eV, respectively. Through comprehensive simulation and optimization applying SCAPS‐1D software, this work investigates the effects of absorber layer thickness, defect density, and doping concentration on the photovoltaic (PV) performance of the proposed PSCs. The results reveal that the DPAL structure (FTO/PCBM/CsSnGeI ₃ /CsSnI ₃ /Au) achieves impressive power conversion efficiency (PCE) of 31.31%, significantly surpassing single absorber designs. The optimized configuration exhibits a short‐circuit current density ( J _SC ) of 35.31 mA/cm ² , an open‐circuit voltage ( V _OC ) of 1.01 V, and a fill factor (FF) of 87.63%. In comparison, CsSnGeI ₃ and CsSnI ₃ ‐based single absorbers achieved PCEs of 27.33% and 28.10%, respectively. These findings demonstrate the potential of the DPAL approach in enhancing light absorption, charge carrier separation, and transport. This study not only deepens the understanding of PSC design and optimization but also lays the groundwork for advanced solar cells designed to achieve higher efficiency and greater environmental sustainability.