One-dimensional BiFeO3 (BFO) nanofibers fabricated by electrospinning of a solution of Nylon6/BFO followed by calcination were used for photocatalytic degradation of contaminants in water. The BFO fibers were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV-Vis spectroscopy. The SEM images of the as-spun samples demonstrated the successful production of nanofibers and the SEM images of the samples after calcination confirmed the integrity of the continuous BFO nanofibers. XRD analysis indicated the dominant presence of BFO phase throughout the calcinated nanofibers. Photocatalytic activity of the nanofibers and their application in water purification were investigated against 4-chlorophenol (4CP) as a model water contaminant. The results of the UV-Vis spectroscopy show the degradation of the 4CP by means of the photocatalytic activity of the BFO nanofibers. The kinetics of the photodegradation of 4CP is believed to be governed by a pseudo-first-order kinetics model. 1. Introduction The presence of hazardous nondegradable contaminants in water such as pharmaceuticals [1] and organic and inorganic solutes [2] poses dangers of human and environmental exposure that result in health effects and environmental damage [3, 4]. A widespread need, therefore, exists for developing cost effective and scalable methods to reduce harmful compounds to a permitted amount or eliminate them entirely. Many methods such as the application of polymeric adsorbents, membrane separation, and oxidation treatments have been proposed [5]. Photocatalysis, a well-known oxidation treatment method, has the advantage of direct absorption of light at room temperature where there is no need for thermal activation to fully mineralize pollutants [6, 7]. Photocatalysis involves photolysis, the breaking down of a chemical compound by the assistance of light, which is accelerated by means of a catalyst. This process can occur in the form of homogeneous as well as heterogeneous photocatalysis. In the former, photocatalysts such as ozone are used and the reactants exist at the same phase as the catalyst. In the latter, however, the reactants are in a different phase from the reactive entity that triggers various oxidation and reduction reactions through which the contaminating agent is degraded [7]. Semiconductors are often applied in this type of photocatalysis. In this case, photocatalysis is activated when photons with sufficient energy excite the electrons of the valence band in the photocatalyst creating electron-hole pairs. Due to the presence of
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