氢氧化镁/还原氧化石墨烯纳米复合材料的制备及光催化性能研究

Preparation and photocatalytic property of MG(OH)/RGO nanocomposite

以六水合氯化镁、氢氧化钠、氧化石墨烯(GO)为原料,己内酰胺为溶剂,通过化学沉淀法制备氢氧化镁/还原氧化石墨烯[Mg(OH)_(2)/RGO]纳米复合材料。研究了反应时间和GO含量对纳米复合材料光催化性能的影响。结果表明:纳米复合材料中GO被原位还原成RGO,Mg(OH)_(2)纳米片负载在RGO表面。所有Mg(OH)_(2)/RGO纳米复合材料对亚甲基蓝的光催化降解都十分高效,在5min内均能将其完全催化降解,这是由于Mg(OH)_(2)纳米片和RGO对亚甲基蓝的光催化降解具有协同作用。其中Mg(OH)_(2)纳米片的大比表面积使其对MB表现出良好的吸附作用,而负载在RGO表面的Mg(OH)_(2)纳米片保证了RGO的光催化效果。此外,反应时间对光催化性能影响不大,而随着GO含量的提高,纳米复合材料的光催化循环使用性能显著提高。

Magnesium hydroxide/reduced graphene oxide[MG(OH)2/RGO]nanocomposites were prepared by the chemical precipitation method with magnesium chloride hexahydrate,sodium hydroxide,and graphene oxide(GO)as raw materials and caprolactam as a solvent.The influences of the reaction time and the amount of GO on the performance of the nanocomposites were investigated.The results showed that GO in nanocomposites was in situ reduced,and Mg(OH)_(2)nanosheets were loaded on the surface of RGO.All Mg(OH)_(2)/RGO exhibited excellent photocatalytic degradation for methylene blue(MB),which could be completely degraded within 5 min.This was due to the synergistic effect of Mg(OH)_(2)nanosheets and RGO on the photocatalytic degradation of MB.The Mg(OH)_(2)nanosheets with large specific surface areas showed good adsorption of MB,and meanwhile,the Mg(OH)_(2)nanosheets loaded on the surface of RGO could guarantee the photocatalytic effect of RGO.Besides,the reaction time had little effect on the photocatalytic performance,but with an increase of the GO content,the reusability of nanocomposites was significantly improved.