Energy-Efficient CuO/TiO₂@GCN Cellulose Acetate-Based Membrane for Concurrent Filtration and Photodegradation of Ketoprofen in Drinking and Groundwater

Photocatalytic membranes possessing both photocatalytic and solid-liquid separation capabilities were developed. These materials are based on ternary 1% CuO/TiO2@GCN (1:9) embedded on cellulose acetate (CA) via the phase inversion method. The CA membranes containing 0.1, 0.3 and 0.5 wt% of 1% CuO/TiO2@GCN (1:9) (CTG–100, CTG–300 and CTG–500) were fabricated. The deposition of 1% CuO/TiO2@GCN (1:9) onto the CA membranes and the consequential changes in the materials’ properties were investigated with various characterization techniques. For instance, PXRD, FTIR, and XPS analysis provided evidence that photocatalytic membranes were formed. Electron microscopy and EDX were then used to visualize the photocatalytic membranes and show that the photocatalyst (1% CuO/TiO2@GCN (1:9)) was well dispersed onto the CA membrane. On the other hand, the properties of the photocatalytic membranes were scrutinized, where it was found that the membranes had a sponge-like morphology and that was significantly less hydrophilic compared to neat CA. The removal of KP in water using CTG–500 exhibited over 94% efficiency, while 38% for neat CA was achieved. Water permeability flux improved with increasing 1% CuO/TiO2@GCN (1:9) and hydrophilicity of the membranes. The electrical energy consumption was calculated and determined to be significantly lower than that of the CA membrane. The CTG–500 membrane after every cycle showed self-cleaning ability after operation in drinking and groundwater

Fabrication of a Polybutylene Succinate (PBS)/Polybutylene Adipate-Co-Terephthalate (PBAT)-Based Hybrid System Reinforced with Lignin and Zinc Nanoparticles for Potential Biomedical Applications

Polybutylene adipate-co-terephthalate (PBAT) was used in an effort to improve the properties of polybutylene succinate (PBS). The resultant blend consisting of PBS/PBAT (70/30) was reinforced with lignin at different loadings (5 to 15 wt.%) and zinc (ZnO) nanoparticles (1.5 wt.%). Hot melt extrusion and injection moulding were used to prepare the hybrid composites. The mechanical, thermal, physical, self-cleaning, and antimicrobial properties of the resultant hybrid composites were investigated. The transmission electron microscopy (TEM) results confirmed that ZnO was successfully prepared with average diameters of 80 nm. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) confirmed that there were interactions between the fillers and the blend. The tensile strength and elongation at the break of the resultant materials decreased with increasing the loadings, while the tensile modulus showed the opposite trend. The melting behaviour of the blend was practically unaffected by incorporating lignin and ZnO nanoparticles. In addition, the incorporation of fillers reduced the thermal stability of the materials. Furthermore, the incorporation of ZnO nanoparticles introduced photocatalytic properties into the polymer blend, rendering it to be a functional self-cleaning material and enhancing its antimicrobial activities

Top-down synthesis of graphene: A comprehensive review

Graphene research has become an emerging frontier in materials science because of its potential as a versatile material in multiple applications, from electronics, sensors, water treatment, batteries, displays, advanced composites, and coatings to biomedical applications. While the community has witnessed tremendous advances in the laboratory-scale synthesis of graphene, it is crucial to focus on sustainable large-scale graphene production to adopt graphene-based technology at an industrial scale. Several top-down and bottom-up methods have been developed to realize affordable graphene production. However, a low-cost scalable graphene production method with acceptable quality remains a challenge; top-down processes are demonstrating their potential to offer a more straightforward solution. Herein, we present an overview of recent progress in the research and development of top-down graphene synthesis methods and their potential to scale-up graphene production. We cover the effect of different synthesis parameters on the quality control of graphene. In addition, we provide a brief overview of bottom-up methods. Finally, we discuss the existing challenges and future directions in top-down methods for large-scale graphene production