Electrospinning has emerged as one of the potential techniques for producing nanofibers. The use of electrospun nanofibers in drug delivery has increased rapidly over recent years due to their valuable properties, which include a large surface area, high porosity, small pore size, superior mechanical properties, and ease of surface modification. A drug loaded nanofiber membrane can be prepared via electrospinning using a model drug and polymer solution; however, the release of the drug from the nanofiber membrane in a safe and controlled way is challenging as a result of the initial burst release. Employing a core-sheath design provides a promising solution for controlling the initial burst release. Numerous studies have reported on the preparation of core-sheath nanofibers by coaxial electrospinning for drug delivery applications. This paper summarizes the physical phenomena, the effects of various parameters in coaxial electrospinning, and the usefulness of core-sheath nanofibers in drug delivery. Furthermore, this report also highlights the future challenges involved in utilizing core-sheath nanofibers for drug delivery applications.

Polymer foams have low density, good heat insulation, good sound insulation effects, high specific strength, and high corrosion resistance, and are widely used in civil and industrial applications. In this paper, the classification of polymer foams, principles of the foaming process, types of blowing agents, and raw materials of polymer foams are reviewed. The research progress of various foaming methods and the current problems and possible solutions are discussed in detail.

Robust and highly fluorescent N-doped carbon dots (CDs) are obtained from a hybrid source, alginic acid and ethanediamine. During a hydrothermal process, the raw materials are propelled to form nano-sized particles; these resultant CDs possess desirable functional groups on the particle surface. We have further investigated their optical performance under various pH conditions as well as their capacity for sensing metal ions. The N-doped CDs especially exhibit remarkable acid-evoked fluorescence enhancement under acidic conditions. Finally, the as-prepared CDs are tested for their ability to detect Fe³⁺ in acidic pure water and urban river water media, and the fluorescence-quenching mechanism and recovery properties of the CD/Fe³⁺ mixture are also investigated.

Carbon-based materials is considered one of the oldest and extensively studied research areas related to gas adsorption, energy storage and wastewater treatment for removing organic and inorganic contaminants. Efficient adsorption on activated carbon relies heavily upon the surface chemistry and textural features of the main framework. The activation techniques and the nature of the precursor have strong impacts on surface functionalities. Consequently, the main emphasis for scientists is to innovate or improve the activation methods in an optimal way by selecting suitable precursors for desired adsorption. Various approaches, including acid treatment, base treatment and impregnation methods, have been used to design activated carbons with chemically modified surfaces. The present review article intends to deliver precise knowledge on efforts devoted by researchers to surface modification of activated carbons. Chemical modification approaches used to design modified activated carbons for gas adsorption, energy storage and water treatment are discussed here.

Photocatalysis has recently emerged as an advanced, green, and eco-friendly process for the treatment of wastewater and air, and antimicrobial disinfection applications. In this context, TiO₂ nanostructures have been shown to be the prominent photocatalyst candidates due to their low cost, non-toxicity, and ease of fabrication. This review highlights the investigation and development of TiO₂ photocatalyst film by sol-gel method with special emphasis on the photodecolorization of synthetic dyes and antibacterial activities. Furthermore, various synthesis methods for the preparation of TiO₂ films and their advantages, as well as limitations, are summarized. Finally, recent advances in TiO₂ films by sol-gel method for dye degradation and antibacterial activities, challenges, and future perspective are discussed.