甘蔗渣碳气凝胶负载纳米氧化锌的制备及其光催化性能研究

Study on preparation and photocatalytic properties of bagasse carbon aerogels loaded with zinc oxide nanoparticles

通过浸渍-煅烧法成功制备出一系列甘蔗渣纤维素基碳气凝胶(BCCA)负载纳米氧化锌复合材料(BCCA/ZnO),并用于降解甲基橙染料(MO)。采用场发射扫描电镜(FE-SEM)、傅里叶变换红外光谱(FT-IR)、X射线衍射(XRD)、X射线光电子能谱(XPS)、紫外-可见光漫反射(UV-Vis DRS)、N_(2)吸附-脱附等测试方法对制备的BCCA/ZnO进行表征测试。研究结果表明,BCCA具有三维多孔网络状结构,经醋酸锌溶液浸泡、高温碳化后,在其表面原位生成球状纳米ZnO颗粒。在模拟紫外光条件下,BCCA/ZnO具有良好的催化活性,当pH=11时BCCA/ZnO-3可以在80 min内对MO的降解率为99%。重复使用4次后,BCCA/ZnO-3在80 min内对MO的降解率为99%,仍然具有优异的催化效果,表明BCCA/ZnO-3具有较好的稳定性和重复使用性。同时,探究了光催化降解机理,发现·OH起主要作用,h^(+)起次要作用,而·O_(2)^(-)不起作用。

A series of bagasse cellulose‐based carbon aerogel‐loaded zinc oxide nanocomposite(BCCA/ZnO)catalysts were successfully prepared by immersion‐calcination method for the degradation of Methyl Orange(MO)dye.The prepared BCCA/ZnO was characterised by field emission scanning electron microscopy(FE-SEM),Fourier transform infrared spec‐troscopy(FT-IR),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),UV-Vis diffuse reflection(UV-visible DRS)and specific surface area,etc.The study revealed that BCCA possessed a three‐dimensional porous network structure.After being soaked in a zinc acetate solution and undergoing high‐temperature carbonisation,spherical ZnO nanoparticles were generated in situ on the surface of BCCA.Excellent catalytic activity of BCCA/ZnO was demonstrated by simulating the UV environment,in which BCCA/ZnO-3 could degrade the MO solution in 80 min for 99%under the opti‐mal conditions of pH=11.After 4 repeated use,the degradation efficiency of BCCA/ZnO-3 for MO was 99%in 80 min,which still showed excellent catalytic effect,indicating that it had good stability and reusability.While,the photocatalytic degradation mechanism was investigated.It was found that·OH played a major role,h+played a minor role,and·O_(2)^(-)did not play a role.