可见光驱动RGO/g-C3N4活化过硫酸盐降解水中双酚A

Visible-light-driven Activation of Persulfate by RGO/g-C3N4 Composites for Degradation of BPA in Wastewater

光催化氧化法能够高效去除水体中的持久性有机污染物,在污水净化领域展现出广阔的应用前景。本研究分别以尿素和双氰胺为原料,采用冷干辅助热聚合法制备了还原性氧化物石墨烯/氮化碳(RGO/g-C3N4)二元可见光催化剂,并对样品的形貌结构和光学性能进行了分析表征。结果表明,二维层状g-C3N4与RGO在异质结界面上紧密的结合在一起。同时以内分泌干扰物双酚A(BPA)为降解污染物,研究了不同催化剂在可见光下活化过硫酸盐去除BPA的活性。光催化实验结果显示,在可见光(λ>420 nm)照射下,加入氧化剂过硫酸盐(PS)作为电子受体,有效地增强了光催化剂可见光降解BPA的活性。以尿素为原料制备的RGO/g-C3N4催化剂在40 min内几乎完全去除溶液中的BPA。经过5次循环反应后,可见光照射40 min,该催化剂对BPA的去除率仍能达到80%以上,表现出良好的稳定性。

Persistent organic pollutants can be effectively removed by photocatalytic oxidation,which reveals potential application prospects in the field of wastewater purification.Binary reduced graphene oxide and graphitic carbon nitride(RGO/g-C3N4)visible-light photocatalyst was successfully fabricated by the freeze drying assisted thermal polymerization method with urea and dicyandiamide as raw materials,respectively.The morphologies,structures and optical properties were characterized by various techniques.It was found that g-C3N4 and RGO nanostructures formed an intimate contact across the heterojunction interface.The photodegradation performances of catalysts were evaluated by removing bisphenol A(BPA)with the activation of persulfate(PS).The results indicated that the photocatalytic activities of photocatalysts were enhanced with the addition of PS as an oxidant and electron acceptor under visible light irradiation(λ>420 nm).Moreover,BPA was almost completely removed by RGO/g-C3N4 prepared with urea as raw material in 40 min.After five recovery tests,the removal efficiency of BPA for the catalyst was up to 80%within 40 min under visible light irradiation,which exhibited superior stability.