g-C_3N_4光催化材料的制备及降解水中头孢曲松钠

Synthesis of g-C_3N_4 photocatalytic materials and applications in degradation of ceftriaxone sodium

采用高温煅烧法成功制备了块状g-C_3N_4和g-C_3N_4纳米材料,利用XRD、SEM、FT-IR、UV-Vis、PL等方法对材料进行表征,并研究其降解头孢曲松钠的光催化活性和机理。当降解时间为120 min、头孢曲松钠质量浓度为10 mg/mL、半导体材料的加入量为0.1 g时,块状g-C_3N_4和g-C_3N_4纳米材料的降解率分别为67.74%和85.84%,g-C_3N_4纳米材料的光催化活性高于块状g-C_3N_4;对催化机制研究发现,空穴(h+)和羟基自由基(·OH)起主要催化作用,超氧自由基(·O_2^-)次之。对g-C_3N_4纳米材料的稳定性进行评价,3次循环催化后材料稳定性良好。

The overuse and misuse of ceftriaxone sodium is a serious issue threating human and ecological health.It is urgent to explore an effective way to eliminate antibiotic residues from the aquatic environment. Bulk g-C3N4 and nanoscale g-C3N4 photocatalytic materials are prepared successfully via high temperature calcination method,and both are characterized by XRD,SEM,FT-IR,UV-Vis and PL,etc. Photocatalytic degradation of ceftriaxone sodium over the asprepared g-C3N4 materials under visible light irradiation is carried out to evaluate the catalytic activity and investigate the catalytic mechanism.The results indicate that the degradation rates over bulk g-C3N4 and g-C3N4 nanosheets are 67. 74%and 85. 84%,respectively when the degradation under visible light irradiation lasts for 120 min,the mass fraction of ceftriaxone sodium is 10 mg·mL^（-1） and the dosage amount of semi-conductive materials is 0. 1 g. The g-C3N4 nanosheets shows much higher photocatalytic activity than bulk g-C3N4.It is found through exploring the catalytic mechanism that h＋and ·OH play major roles in catalytic actions,·O2-- comes next.Moreover,the as-prepared g-C3N4 nanosheets samples are of high stability after three times of uses.