柠檬酸络合sol-gel法原位合成rGO-La3 /TiO2及其光催化性能

Photocatalytic Property of rGO -La3 / TiO2 Composites In-situ Synthesis by a Citric Acid Chelated Sol-gel Method

摘要:

首先采用Hummers法制备氧化石墨烯（GO），然后用柠檬酸络合溶胶-凝胶法原位合成GO-La3 /TiO2，再经硼氢化钠还原得到石墨烯-La3 /TiO2（rGO-La3 /TiO2）复合材料；利用X射线衍射（XRD）、透射电镜（TEM）、荧光光谱（PL）对其进行表征分析。研究了GO加入量对复合材料光催化效率的影响及复合光催化剂投入量对甲基橙降解率的影响。结果表明：柠檬酸络合法可以有效改善纳米La3 /TiO2在rGO表面的分散情况；rGO-La3 /TiO2复合光催化剂的光催化活性明显高于La3 /TiO2，GO加入量对复合材料光催化性能影响很大；降解甲基橙时，复合光催化剂最佳投入量为0.10g。

Abstract:

Graphene oxide (GO) was prepared by Hummers method, then a series of composites consisting of lanthanum doped titanium dioxide and graphene oxide （GO-La3 /TiO2）were in situ synthesized via citric acid chelating sol-gel step, and subsequently lanthanum doped titanium dioxide and graphene (rGO-La3 /TiO2) composite photocatalysts were obtained by sodium borohydride reduction method. The composite materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy technology. The influences of GO addition amount on the composites photocatalytic activity and the effects of composite photocatalysts mass on the methyl orange degradation rate were investigated, respectively. The results showed that the dispersion of lanthanum doped nanometer titanium dioxide on the graphene surface was improved effectively; the photocatalytic activity of rGO-La3 /TiO2 was obviously higher than that of La3 /TiO2, and the photocatalytic performance of rGO-La3 /TiO2 was effected greatly by the addition amount of GO; the optimum mass of composite photocatalysts was 0.10g to degradation of methyl orange.