多维异质结光催化剂g-C_(3)N_(4)/WO_(3)的制备及应用

Preparation and application of multi-dimensional heterojunction photocatalyst g-C_(3)N_(4)/WO_(3)

采用原位热聚合法和溶剂热法分别合成了片状和球状两种g-C_(3)N_(4)/WO_(3)异质结,运用XRD、SEM和UV-Vis DRS等手段进行了表征,并考察了两种异质结对盐酸四环素(TC-HCl)的光催化降解效果。表征结果显示,二维(2D)g-C_(3)N_(4)/WO_(3)呈现堆叠或卷曲的不规则纳米片状,三维(3D)g-C_(3)N_(4)/WO_(3)由大量直径为1~5μm的纳米微球组成。实验结果表明:2D g-C_(3)N_(4)/WO_(3)比3D g-C_(3)N_(4)/WO_(3)具有更强的光催化活性,在TC-HCl质量浓度10 mg/L、光催化剂加入量200 mg/L的条件下,暗反应60 min后,再转用氙灯(500 mW/cm^(2))照射60 min,2D g-C_(3)N_(4)/WO_(3)和3D g-C_(3)N_(4)/WO_(3)对TC-HCl的去除率分别为98.96%和41.15%;在2D g-C_(3)N_(4)/WO_(3)光催化降解TC-HCl的体系中,·O_(2)^(-)、·OH和h^(+)对TC-HCl降解的影响顺序为·O_(2)^(-)>·OH>h^(+)。

Two forms of g-C_(3)N_(4)/WO_(3)heterojunction materials,sheet and sphere,were synthesized by in-situ thermal polymerization or solvothermal method,and characterized by XRD,SEM and UV-Vis DRS.The photocatalytic degradation effects of tetracycline hydrochloride(TC-HCl)by the two heterojunction materials were investigated.The characterization results show that the two-dimensional(2D)g-C_(3)N_(4)/WO_(3)exhibits a stacked or curled irregular nanosheet shape,and the three-dimensional(3D)g-C_(3)N_(4)/WO_(3)is composed of a large number of nanospheres with a diameter of 1-5μm.The experimental results show that:Under the conditions of TC-HCl mass concentration 10 mg/L,photocatalyst amount 200 mg/L,dark reaction time 60 min,and xenon lamp(500 mW/cm^(2))irradiation time 60 min,the removal rates of TC-HCl by 2D g-C_(3)N_(4)/WO_(3)and 3D g-C_(3)N_(4)/WO_(3)is 98.96%and 41.15%,respectively,indicating that 2D g-C_(3)N_(4)/WO_(3)has stronger photocatalytic activity than 3D g-C_(3)N_(4)/WO_(3);In the system of photocatalytic degradation of TC-HCl by 2D g-C_(3)N_(4)/WO_(3),The order of the effects of·O_(2)^(-),·OH and h+on the degradation of TC-HCl is·O_(2)^(-)>·OH>h^(+).