静电纺丝制备g-C3N4/C纳米纤维及其可见光降解性能

采用g-C_3N_4纳米片与聚丙烯腈进行静电复合纺丝,再经预氧化和碳化制得g-C_3N_4/C纳米纤维。利用傅立叶变换红外光谱仪(FTIR)、X射线衍射仪(XRD)、拉曼光谱(Raman)和扫描电子显微镜(SEM)对样品结构和形貌进行表征,通过紫外-可见漫反射光谱(UV-Vis DRS)分析可见光响应性。研究表明,复合纳米纤维对罗丹明B表现出较好的可见光降解活性,源于无定形相/石墨相混合结构的碳基体能够降低g-C_3N_4的光生电子-空穴对复合的几率。复合纳米纤维膜在光催化降解搅拌条件下始终能保持完整,经过多次回收和光催化实验,对罗丹明B的光降解率依然较高,表现出较优异的循环利用稳定性。

Synthesis of g-C3N4/C Nanofibers by Electrospinning and Their Photodegradation Performance under Visible Light

g-C₃N₄/C composite nanofibers were prepared via a combination process of electrospinning, preoxidation and carbonization by using g-C₃N₄ nanosheets and polyacrylonitrile as raw materials. Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), Raman spectroscopy (Raman) and scanning electron microscopy (SEM) were employed to analyze the structure and morphology of the as-synthesized nanofibers. And UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS) was used to assess their visible light response. The results show that the g-C₃N₄/C composite nanofibers exhibit good photocatalytic degradation activity toward rhodamine B under visible light, which originates from better ability of their partially amorphous carbon matrix to reduce the combination of the photogenerated electron and hole pair. The nanofiber membrane was not embrittled into powers or small flakes during the photocatalytic degradation process under stirring conditions, maintaining its integrity from begin to end. After several recovery and photocatalysis experiments, the membrane still maintained high photodegradation rate. This study reveals that the resulting nanofibers have excellent recycling stability to photodegradate rhodamine B under visible light.