氮化碳分散液的制备及其光催化性能

Preparation and photocatalytic properties of carbon nitride dispersions

以尿素热解得到的块状体相氮化碳为前驱体,采用硫酸质子化结合超声剥离的方法制备氮化碳纳米片分散液,考察不同工艺条件如溶剂种类、稳定剂浓度、氮化碳原料浓度、超声时间等对其分散性的影响。通过UV-Vis、FTIR、XRD、SEM、BET等方法对分散液的浓度、结构、微观形貌和比表面积进行表征分析;并以亚甲基蓝为目标降解物,研究其在可见光照射下的光催化性能。结果表明,以水为溶剂、ρ(稳定剂)=1.2 mg/mL、ρ(氮化碳)=1.0 mg/mL、超声时间为18 h制备的氮化碳纳米片分散液性能最好,其在可见光照射180 min后对亚甲基蓝的光催化降解率达77.93%。

The bulk carbon nitride obtained from the pyrolysis of urea was used as the precursor to prepare the dispersion of carbon nitride nanosheets by the method of sulfuric acid protonation and ultrasonic stripping.The effects of different process conditions such as solvent type,stabilizer concentration,carbon nitride raw material concentration and ultrasonic time on the dispersibility of g-C 3N 4 were investigated.The concentration,structure,micro morphology and specific surface area of the dispersion were characterized by UV-Vis,FTIR,XRD,SEM and BET,and the photocatalytic performance of methylene blue under visible light was studied.The results showed that the dispersion with optimum process conditions of water as solvent,the stabilizer concentration of 1.2 mg/mL,carbon nitride concentration of 1.0 mg/mL and ultrasonic time of 18 h had the best performance.The photocatalytic degradation rate of methylene blue reached 77.93%after 180 min of visible light irradiation.