| In recent years, water pollution has become more and more severe, which has threatened the safety of human beings. Many methods have been adopted to solve this problem, like electrolytic oxidation method, biotechnology law, adsorption method and so on. However, these methods not only have high cost, but also their efficiency is very low. So far, semiconductor photocatalytic technology has been attracted considerable attention owing to its efficiency, low cost and wide source. And in most semiconductor photocatalytic technologies, LaFeO3has eminent features in optics, electricity, magnetics, which has received extensive attention.In this study, we reported the synthesis of LaFeO3via a facile electrospinning technique, in which the Fe(NO3)3·9H2O, Ci5H2iFe06, La(NO3)3·6H2O and PVP-K30were selected as the raw materials. The author has explored what effects have been given to the preparation of nanofibers by different salt systems, solvent additives and spinning needles. The results showed that C15H2iFeO6and La(NO3)3·6H2O were dissolved in lOmL ethyl alcohol to obtain the precursor solution. The precursor solution is more beneficial to spin under low voltage and the situation that the spinning needles may be jammed is also solved at the same time. After the experiment of photocatalysis, it is concluded that ribbon-like LaFeO3composite nanofibers were prepared by coaxial needle exhibiting excellent photocatalytic activity.In this study, we also found that the fibers morphology can be easily adjusted by changing the calcination temperatures. when the fibers calcination at400℃, they are adhesion together. when the fibers calcination at500℃and600℃respectively, they are long and porous ribbon-like LaFeO3composite nanofibers. And when the nanofibers calcination at700℃, the porous nanobelts are get shorter. After analyzing by XRD, the results that this series of fiber is orthorhombic system and there is no other impurities appearing. After the experiment of photocatalysis, its order is500℃>600℃>700℃>400℃, which is mainly affected by both the grain size and the superficial area of fibers. The article prepared ribbon-like LaFeO3composite nanofibers with different quantity of Ag under500℃by adopting the electrospinning method. It comes to the conclusion that this series of fiber presented good shapes of ribbon. When the quantity of Ag is up to15wt%, the peak of Ag appeared. And as the quantity of Ag increased, the peak of Ag and LaFeO3in the samples also increased. Otherwise, the nanoparticles in the fiber increased with the quantity of Ag increasing. After the photocatalytic test, the ribbon-like15wt%Ag-LaFeO3nanofibers are exhibit excellent photocatalytic activity, which is up to92.8%.The ribbon-like15wt%Ag-LaFeO3nanofibers can be calcination under different temperatures. From the SEM, it is found that the temperature has great effect on the morphology of the fibers. When the temperature is400℃, the fibers adhesion together strongly and its shape is not so obvious. When it is up to500℃, the fibers comes to the structures with porous ribbon-like15wt%Ag-LaFeO3nanofibers. When600℃, a small amount of the ribbon-like15wt%Ag-LaFeO3nanofibers happening ruptures. When700℃, most ribbon-like15wt%Ag-LaFeO3nanofibers get shorter. As the temperature of calcination increased, the nanoparticles in the fiber increase from17.5nm to40.1nm. After the photocatalytic test, the best calcination temperature is500℃and the degradation rate is92.8%. |
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