质子化氮化碳的制备及其复合材料的光催化性能

分别采用硫酸、盐酸和硝酸对尿素热解得到的体相块状石墨相氮化碳(g-C_3N_4)进行质子化改性,超声剥离得到氮化碳纳米片,考察3种质子化氮化碳纳米片对亚甲基蓝染料的光催化降解性能,利用XRD、FT-IR、SEM、BET、UV-DRS、UV-VIS等对其结构、形貌、比表面积、禁带宽度进行分析。结果表明,硫酸改性后的g-C_3N_4比表面积最大(60. 9 m~2·g~(-1)),亚甲基蓝降解效果最好,降解率为46. 7%,相比于体相块状g-C_3N_4的29. 2%提高了17. 5个百分点。以硫酸质子化改性的g-C_3N_4为前驱体,采用搅拌法制备得到质子化g-C_3N_4/石墨烯复合材料,其光催化降解亚甲基蓝的降解率为81. 7%,较硫酸质子化g-C_3N_4提高了35. 0个百分点。

Synthesis and photocatalytic properties of protonated carbon nitride and its composites

Three kinds of acids(H₂SO₄,HCl and HNO₃) were used to protonize the bulk graphitic carbon nitride(g-C₃N₄) which was obtained from the pyrolysis of urea,then the flaked g-C₃N₄was obtained by ultrasonic sepration.The photocatalytic degradation of methylene blue over three kinds of protonated carbon nitrides was investigated.The structure,morphology,specific surface area,and band gap widthwere characterized by XRD,FT-IR,SEM,BET,UV-DRS and UV-VIS.The results showed that the specific surface area of g-C₃N₄ protonated by H₂SO₄ was the largest(60.9 m²·g^-1) and the degradation of methylene blue was the highest of 46.7%,which was 17.5% higher than that of bulk g-C₃N₄(29.2%).Protonated g-C₃N₄/graphene composites were prepared by stirring method using protonated g-C₃N₄ modified by H₂SO₄ as precursor.The photocatalytic degradation of methylene blue was 81.7%,which was 35.0% higher than that of protonated g-C₃N₄ modified by H₂SO₄.