Preparation,Characterization And Characterization Of BiFeO₃ Nanofibers By Electrospinning

Bismuth ferrite?BiFeO₃;BFO?is the only single-phase ABO3 perovskite compound with multi-iron properties at room temperature,and has great potential in new multifunctional materials,new magnetic-electric sensors,and spintronic devices.Nano-ferroelectric materials are very important for the development of future electronic and information technology.Compared with ceramic blocks and thin films,low-dimensional BFOs show significant differences in functional properties due to the large increase in surface area of BFO nanostructures.Poly?N-isopropylacrylamide??PNIPAm?is one of the most widely studied temperature-sensitive polymer materials.Due to PNIPAm,it can perform fast and reversible phase conversion at 32-34 0C?lower critical solution temperature LCST?.It has good biocompatibility and is widely used in special functional fibers and controlled release of drugs.It has good application prospects in the field of sensors and separation.In the research work of this paper,BFO/PVP and BFO/PNIPAm nanofibers were prepared by sol-gel-based electrospinning method,and the influence of sample spinning parameters on morphology,chemical composition,crystal structure and thermal stability were studied.The optical properties are systematically studied.BFO/PVP nanofibers were successfully prepared by sol-gel based electrospinning.The experimental results show that the sample with the optimum annealing temperature of BFO/PVP fiber at 500? and the annealing at 500 ? is in good agreement with the standard card.It is a pure phase and belongs to the perovskite structure.Exploring the influence of voltage and collector receiving distance on electrospun BFO/PVP nanofibers,the optimal spinning parameter voltage was 15 kV and the receiving distance was 15 cm.The band gap was calculated by UV spectroscopy to analyze the cause of the change in the band gap value of the sample.The BFO/PNIPAm nano fibers were then successfully prepared using a sol-gel based electrospinning process.The experimental results show that the average diameter of BFO/PNIPAm nanofibers after annealing at 500 C is 477.15 nm,the fiber thickness distribution is relatively uniform,and the surface morphology is smooth,which is thicker than the average diameter of PNIPAm and BFO/PVP nanofibers in the same spinning process.The BFO/PNIPAm nanofibers all have characteristic peaks of PNIPAm,and the BFO/PNIPAm nanofibers after annealing have a BFO characteristic peak,corresponding to a perovskite structure.The decomposition temperature of BFO/PNIPAm is 2.4?,higher than PNIPAm,the thermal stability of the fiber is increased,and the LCST is reduced by 0.9 0C,which reduces the hydrophilic effect and improves the temperature sensitivity of PNIPAm.BFO/PNIPAm is more hydrophobic than PNIPAm and exhibits good temperature-sensitive behavior.