In this paper, quasi-solid-state dye-sensitized solar cell has been constructed based on natural photosensitizers extracted from the bracts of Bougainvillea spectabilis and the leaves of Euphorbia cotinifolia using acidified (0.1 M HCl) distilled water and ethanol separately. The absorption spectra of the extracts were performed in the spectral range from 395 to 750 nm. The cells were assembled using commercial TiO 2 powder film and PEDOT coated FTO glasses as working and counter electrodes, respectively, and also the quasi-solid electrolyte sandwiched in between. The Photovoltaic parameters such as short circuit current density (J sc ), open circuit voltage (V oc ), fill factor (FF), and overall conversion efficiency (g) for the as-prepared DSSC were determined under 100 mW/ cm 2 illuminations. The highest open circuit voltage (V oc = 0.549 V) and short circuit current density (J sc = 0.592 mA/cm 2 ) were obtained from the DSSCs assembled by natural dye extracted with the acidified ethanol of Bougainvillea spectabilis bracts and the leaves of Euphorbia cotinifolia, respectively. The highest power conversation efficiency (g) of the as-prepared DSSC assembled with natural dye extracted from Bougainvillea spectabilis bracts using acidified ethanol as extracting solvent was 0.175 %. The use of Bougainvillea spectabilis and Euphorbia cotinifolia pigments as natural sensitizers along with the use of quasi-solid electrolyte and PEDOT coated FTO counter electrodes could be a possible alternative for the production of low-cost and environment friendly DSSCs.

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The mechanical properties of single Yushania alpina bamboo fibers have not been explored. This is a serious limitation on their application. The main purpose of this work is to fill up information gaps to prepare for the growing usage of Ethiopian bamboo in a variety of applications. This study looks at the characterization and optimization of Y.alpina bamboo fiber properties extracted both chemically and mechanically. Using response surface methodology (RSM) the mechanical properties were optimized and linear, quadratic and interaction of independent variables were determined. Samples of length 25–30 cm were harvested at various ages from the middle of the stem which was then soaked in different NaOH concentrations weight by volume for different times. Using a rolling machine that has three rollers, the fiber is mechanically extracted. The optimal mechanical properties were observed at plant age of 1.8 years, alkali concentration of 10%, and a soaking duration of 2.0 days. The model is significant (P ≤ 0.005) with a 95% confidence level for predicted values that were closer to the measured values, indicating that the model's fit to the measured properties was strong at the optimized values. The optimized points of age and soaking duration ware subjected to chemical, thermal and morphological analysis for each corresponding NaOH Concentration (6, 12, and 18%) levels. Scanning electron microscopy (SEM) was employed to examine the microstructure of the fibers and discovered that the 18% NaOH treated fiber resulted in more wrinkles in the surface of bamboo fibers when compared with the 6 and 12%NaOH Bamboo fiber. Using thermogravimetric analysis (TGA) and differential thermal gravimetric (DTG), the study investigated weight loss increased as alkali concentration increased but the scenario functioned for proper concentration.

Nowadays, addressing the drawbacks of liquid electrolyte-based batteries is a hot and challenging issue, which is supposed to be fulfilled through solid electrolyte systems such as polymer electrolytes. Polymer blend electrolytes (PBEs) are widely investigated as viable options to solve the undesired characteristics of their liquid counterparts and also the poor ionic conductivity of homopolymer-based electrolytes. Even though PBEs outperform homopolymer-based electrolytes in terms of performance, the conductivity of pristine PBEs is quite low for practical applications (i.e. below 10–3 S/cm at room temperature). A very promising approach to solve this limitation is to incorporate additives into the electrolyte systems, to select suitable polymeric materials and to employ the desired synthesizing techniques as the performance of PBEs is strongly dependent on the selection of polymeric materials (i.e. on the inherent properties of polymers), the nature and amount of salts and other additives, and also the techniques employed to synthesize the polymer blend hosts and/or polymer blend electrolytes, determining the functionality, amorphousness, dielectric constant, dimensional stability, and, ultimately, the electrochemical performances of the system. This paper reviews the different factors affecting the miscibility of polymer blends, PBEs synthesizing techniques, the thermal, chemical, mechanical and electrochemical characteristics of PBEs, and also the challenges and opportunities of PBEs. Moreover, the paper presents the current progress of polymer blend electrolytes as well as future prospects for advancing polymer blend electrolytes in the energy storage sectors.

In the present study, a new biochemical sensor material of conductive Silver (Ag) reinforced polyaniline (PANI)-Benzimidazole copolymer nanocomposite was fabricated via in-situ chemical oxidative polymerization method for the detection of endotoxin. The fabricated PANI-Benz-Ag nanocomposite was characterized by FTIR, XRD, UV-Visible spectrometer, DSC, TGA, Zeta-potential, SEM, TEM, and Confocal fluorescence imaging microscopy. The measured particle size, zeta-potential, and conductivity of the PANI-Benz-Ag nanocomposite were 4.942nm, -10.4mV, and 73.7μS/cm respectively. The crystallite size of Ag nanoparticles was around 67 nm calculated by XRD analysis and TGA analysis was used to determine weight losses and thermal stabilities of PANI-Benz and PANI-Benz-Ag nanocomposite. The endotoxin E. Coli bacteria detection ability of the synthesized PANI-Benz-Ag nanocomposite-based biochemical sensor using DMMB dye displacement assay through the hitchhiking method by confocal fluorescence microscopy was found to be effective. The synthesized electrochemical biosensor can avoid the diagnostic methods for the next generation by applying too early detection of bacteria from adulterated and putrefied food.