硫酸根对聚合氮化碳光催化活性的影响

在pH=1条件下分别加入硫酸根、硝酸根、磷酸根对三聚氰胺进行处理，采用高温煅烧法制备了一系列聚合氮化碳材料，并通过X射线衍射（XRD）、扫描电子显微镜（SEM）、紫外-可见漫反射光谱（UV-Vis DRS）等分析手段对样品进行了表征。以罗丹明B（RhB）为污染物，探究了在可见光下聚合氮化碳对RhB的光催化降解性能、稳定性以及降解机理。加入0.12 mol硫酸根处理的聚合氮化碳（CN-0.04SO₄^2-）在45 min内对RhB的降解率为99.1%，其伪一级动力学常数是未加硫酸根的23.0倍，硫酸根能有效地增强聚合氮化碳的光催化活性。CN-0.04SO₄^2-经过3次循环实验对RhB的降解率略有下降，说明其具有良好的稳定性。活性物种捕获实验表明，影响光催化降解RhB的主要活性物种是·O₂^-和·OH。

Effect of sulfate on photocatalytic activity of polymerized carbon nitride

A series of polymerized carbon nitride were prepared by high temperature calcination method after the treatment of melamine with adding SO₄^2-，NO₃^- and PO₄^3- under the condition of pH=1，respectively.The samples were characterized by X-ray diffraction（XRD），scanning electron microscopy（SEM），UV-Visible diffuse reflectance spectroscopy（UV-Vis DRS），etc.Using rhodamine B（RhB） as pollutant，the photocatalytic degradation activity，stability and degradation mechanism of polymerized carbon nitride were explored under visible light.The degradation of RhB by polymerized carbon nitride（CN-0.04SO₄^2-） with 0.12 mol SO₄^2- was 99.1% within 45 min，and its pseudo?first?order kinetic constant was 23.0 times greater than that of no SO₄^2-.SO₄^2-，which could effectively enhance the photocatalytic activity of polymerized carbon nitride.The degradation of CN-0.04SO₄^2- was decreased slightly after three cycles，indicating that it had good stability.Active species capture experiment showed that ·O₂^- and ·OH were the main active species affecting photocatalytic degradation of RhB.