Room Temperature Synthesized TiO(2) Nanoparticles for Two-Folds Enhanced Mechanical Properties of Unsaturated Polyester

Optimized Cu-doping in ZnO electro-spun nanofibers for enhanced photovoltaic performance in perovskite solar cells and photocatalytic dye degradation

Perovskite solar cells (PSCs) compete with conventional solar cells regarding their low-temperature processing and suitable power conversion efficiency. In PSCs, the electron transport layer (ETL) plays a vital role in charge extraction and avoiding recombination; however, poor charge transport of ETL leads to high internal resistance and associated low fill factors. To successfully resolve this challenge, copper-doped zinc oxide nanofibers as an electron transport layer are prepared with various doping levels of 1, 2, and 3 wt% using the electrospinning sol-gel method. The 3 wt% doping of Cu revealed the optimum performance as an ETL, as it offers an electrically efficient transporting structure. SEM images revealed a randomly oriented distribution of nanofibers with different sizes having mesoporous uniformity. Optical properties of doped nanofibers examined using UV-visible analysis showed an extended light absorption due to heteroatom-doping. Adding Cu into the ZnO leads to enhanced charge mobility across the electron transport material. According to Hall measurements, dopant concentration favors the conductivity and other features essentially required for charge extraction and transport. The solar cell efficiency of ZnO doped with 0%, 1%, 2%, and 3% Cu is 4.94%, 5.97%, 6.89%, and 9.79%, respectively. The antibacterial and photocatalytic activities of the prepared doped and undoped ZnO are also investigated. The better light absorption of Cu-ZnO showed a pronounced improvement in the photocatalytic activity of textile electrodes loaded with doped ZnO. The dye degradation rate reaches 95% in 180 min under visible light. In addition, these textile electrodes showed strong antibacterial activity due to the production of reactive oxygen species under light absorption.

Cyclic Thermomechanical Loading of Epoxy Polymer: Modeling with Consideration of Stress Accumulation and Experimental Verification

Developing a viscoelastic model for the cyclic thermomechanical loading of thermosetting polymers is the main goal of this study. The model includes memory for residual thermal stresses and can consider stress accumulation across many loading cycles. By considering stress accumulation, we can improve predictions and understand how thermosetting polymers' stress-strain state changes under cyclic thermomechanical loading. This approach was validated through experimental verification to ensure its applicability in practical engineering scenarios. The experiment showed that the thermosetting polymer can accumulate stress during cycles of heating and mechanical loading during use. The results of the modeling and experiment are compared. The results have led to corrections in the way this model is applied to thermosetting polymers like the epoxy resin in this study. The corrected results matched well with the experimental measurements of stress under cyclic thermomechanical load, with a difference of only 1 to 6%.

Facile-Solution-Processed Silicon Nanofibers Formed on Recycled Cotton Nonwovens as Multifunctional Porous Sustainable Materials

Limited efficiency, lower durability, moisture absorbance, and pest/fungal/bacterial interaction/growth are the major issues relating to porous nonwovens used for acoustic and thermal insulation in buildings. This research investigated porous nonwoven textiles composed of recycled cotton waste (CW) fibers, with a specific emphasis on the above-mentioned problems using the treatment of silicon coating and formation of nanofibers via facile-solution processing. The findings revealed that the use of an economic and eco-friendly superhydrophobic (contact angle higher than 150°) modification of porous nonwovens with silicon nanofibers significantly enhanced their intrinsic characteristics. Notable improvements in their compactness/density and a substantial change in micro porosity were observed after a nanofiber network was formed on the nonwoven material. This optimized sample exhibited a superior performance in terms of stiffness, surpassing the untreated samples by 25-60%. Additionally, an significant enhancement in tear strength was observed, surpassing the untreated samples with an impressive margin of 70-90%. Moreover, the nanofibrous network of silicon fibers on cotton waste (CW) showed significant augmentation in heat resistance ranging from 7% to 24% and remarkable sound absorption capabilities. In terms of sound absorption, the samples exhibited a performance comparable to the commercial standard material and outperformed the untreated samples by 20% to 35%. Enhancing the micro-roughness of fabric via silicon nanofibers induced an efficient resistance to water absorption and led to the development of inherent self-cleaning characteristics. The antibacterial capabilities observed in the optimized sample were due to its superhydrophobic nature. These characteristics suggest that the proposed nano fiber-treated nonwoven fabric is ideal for multifunctional applications, having features like enhanced moisture resistance, pest resistance, thermal insulation, and sound absorption which are essential for wall covers in housing.