Ag/g-C3N4复合微纳米光催化剂的合成及其降解性能

Synthesis and degradation performance of Ag/g-C3N4 micro-nano composite photocatalysts

以尿素为原料,通过高温热缩聚法制备出石墨相氮化碳(g-C3N4),并通过超声剥离,破坏g-C3N4层状结构,得到分散的片状结构。将不同量的硝酸银配成银氨溶液,抗坏血酸将其还原成银,并在搅拌下沉积在g-C3N4的表面,得到不同银负载量的Ag/g-C3N4。利用X-射线衍射仪、纳米粒度仪以及红外光谱仪对其进行表征。最后在紫外-可见光谱仪的测试下,通过降解甲基橙和罗丹明B,比较光催化剂对降解物的选择性降解。结果表明:在可见光的照射下,由90mg硝酸银与100mgg-C3N4制备的复合光催化材料表现出最佳的降解效果,远大于复合之前g-C3N4的降解效果。而且对罗丹明B的降解性大于甲基橙,表明光催化材料对降解物具有选择性。

Graphite phase carbon nitride(g-C3N4)was prepared from urea by high-temperature thermal condensation.The g-C3N4 laminar structure was destroyed by ultrasonic stripping,and the dispersed laminar structure was obtained.Silver was prepared with the reduction of silver nitrate in silver ammonia solution by ascorbic acid and deposited on the surface of g-C 3N 4 under stirring.The Ag/g-C3N4 with different silver loading was obtained.It was characterized by X-ray diffractometer,nano-particle size analyzer and infrared spectrometer.Finally,the selective degradation of methyl orange and rhodamine B was compared by UV-Vis spectrometer.The results showed that the composite photocatalytic material prepared from 90 mg silver nitrate and 100 mg g-C3N4 under visible light showed the best degradation effect,which was much higher than that of g-C3N4.Moreover,the degradation of rhodamine B was higher than that of methyl orange,which proved that the photocatalytic material had selectivity for degradation.