茎秆模板诱导合成g-C_(3)N_(4)/C及其光催化降解四环素研究

Synthesis of g-C_(3)N_(4)/C induced by stem template and photocatalytic degradation of tetracycline

为解决残留在环境中的抗生素给生物带来的巨大危害和潜在威胁,以芦蒿茎秆(较高的纤维素含量)和豆芽茎秆(较低的纤维素含量)作为生物模板,利用茎秆表面凹凸不平的结构作为微反应空间来控制局部双氰胺量并作为结晶晶核,诱导合成薄片状石墨相氮化碳(g-C_(3)N_(4)),并考察其光催化降解四环素性能。通过X射线衍射、扫描电子显微镜、透射电子显微镜和荧光光谱测试等方法对材料进行了表征,结果表明g-C_(3)N_(4)成功负载在生物炭基体的表面,并且薄片状g-C_(3)N_(4)在生物炭基上分散性较高、团聚体相较低。在模拟可见光照射30 min下,茎秆模板和双氰胺质量比为1:2时合成的g-C_(3)N_(4)/C对四环素(TC)表现出了较好的的降解效率,分别为31.7%和26.1%。循环四次后,ACN-2对TC的降解效率从31.7%下降到27.2%,表明材料的光催化循环稳定性良好。

To solve the great harm and potential threat caused by antibiotics left in the environment,Artemisic stalk(high cellulose content)and bean bud(low cellulose content)stalk were used as biological templates to synthesis g-C_(3)N_(4)/C photocatalytic materials.The uneven structure of the stem surface was used as a micro-reaction space to control the amount of local dicyandiamide and as a crystalline nucleus to induce the synthesis of sheet graphite phase carbon nitride(g-C_(3)N_(4))and the photocatalytic degradation of tetracycline was investigated.The material was characterized by X-ray diffraction,scanning electron microscopy,transmission electron microscopy and fluorescence spectroscopy.The results showed that g-C_(3)N_(4)was successfully loaded on the surface of biochar matrix,and the dispersion of g-C_(3)N_(4)on biochar matrix is higher and the agglomeration is lower.Under simulated visible light irradiation for 30 min,g-C_(3)N_(4)/C synthesized at the mass ratio of stem template to dicyandiamide 1:2 showed highest degradation efficiency for tetracycline(TC),which was 31.7%and 26.1%,respectively.After four cycles,the TC degradation efficiency of ACN-2 decreased from 31.7%to 27.2%,indicating the good photocatalytic cycle stability of the material.