The development of new materials with specific functionalities for certain applications has been increasing with the advent of nanotechnology. A technique widely used for this purpose is electrospinning, because control of several parameters involved in the process can yield nanoscale fibers. In addition to the production of innovative and small-scale materials, through structural, chemical, physical, and biological modifications in the fibers produced in electrospinning, it is possible to obtain specific properties for a given application. Thus, the produced fibers can serve different purposes, such as in the areas of sensors, catalysis, and environmental and medical fields. Given this context, this article presents a review of the electrospinning technique, addressing the parameters that influence the properties of the fibers formed and some techniques used to modify them as specific treatments that can be conducted during or after electrospinning. In situ addition of nanoparticles, changes in the configuration of the metallic collector, use of alternating current, electret fibers, core/shell method, coating, electrospray-coating, plasma, reinforcing composite materials, and thermal treatments are some of the examples addressed in this work. Therefore, this work contributes to a better comprehension of some of the techniques mentioned in the literature so far.

The growing increase in emissions of ultrafine particles or nanoparticles by industries and urban centers has become worrisome due to the potential adverse health effects when inhaled. Particles in this size range have greater ease of pulmonary penetration, being able to access the bloodstream and deposit in other regions of the body. Thus, the development and optimization of equipment and processes aimed at the removal of aerosols of nanoparticles have been gaining importance in this current scenario. Among the equipment commonly used, electrostatic precipitators and filters stand out as being versatile and consolidated processes in the literature. This review explores and analyzes the theoretical bases of these two processes in the collection of such small particles in addition to providing a general overview of the development of technologies and studies on these topics.

Although recycled poly(ethylene terephthalate) (rPET) is an attractive, sustainable feedstock for electrospinning, optimization of processing variables for filtration performance remains limited. This study quantifies how polymer concentration, flow rate, and applied voltage govern fiber morphology and key filtration metrics—collection efficiency (η), pressure drop (ΔP), quality factor (Q_f), and porosity—in rPET membranes. A fractional factorial design was employed to model interactions and identify trade-offs in filtration performance. The optimal condition was obtained at 16 wt.% PET, 1.2 mL·h⁻¹, and 22 kV, yielding uniform fibers with an average diameter of 328.6 nm and high filtration efficiencies (95.65–99.99%). The permeability constants were 1.07 × 10⁻¹² m² (20 wt.% PET) and 1.15 × 10⁻¹³ m² (8 wt.% PET), indicating an increase in permeability with increasing polymer concentration and fiber diameter. The 20 wt.% PET membrane delivered the highest Q_f of 0.0646 Pa⁻¹ with a low ΔP of 48.5 Pa at 4.8 cm·s⁻¹, reflecting a favorable balance between collection and airflow resistance. In summary, higher PET concentrations reduce flow resistance and improve Q_f, whereas lower concentrations yield finer fibers and high η at the expense of permeability. rPET nanofiber membranes, therefore, represent a sustainable and versatile route to high-efficiency, lower-pressure-drop air filters for residential, industrial, and commercial environments.

The air is a fundamental element for the life on Earth. Rapid urbanization and industrialization release large amounts of pollutants (harmful gases, microorganisms, and particulate matter, among others) into the atmosphere, leading to health hazards. Air filtration is still the most used and promising technique for protecting air against pollutants. The quality and efficiency of filtering process are dependent of material used for the filter and other filter’s properties. Several methods can be used for manufacturing filters, one of them uses fibrous membranes obtained through electrospinning from polymeric solutions. Electrospinning is a technique that combines the application of an electrostatic field to a moving fluid which results in the fibers formation. Electrospun membranes are constituted by fibers that the sizes spread on submicro and or nanometric scales. This review focuses on fiber membranes obtained by electrospinning for filtration of particulate matter. It is addressed the effect of solution, processing and ambient parameters on the morphology and dimensional characteristics of fiber membranes. The basic principles of air filtration and test and characterization of filter performance are presented. The research progress on electrospun nanofibers as air filters in recent years is summarized and examined. Finally, conclusion and future perspectives in electrospun fibers for air filtration are provided and discussed.

A utilização de fotocatalisadores na degradação de efluentes tem-se demonstrado eficiente devido as suas propriedades oxidativas, sendo necessário, portant...