TiHAP@g-C_(3)N_(4)异质结的制备及光催化降解甲基橙  

Preparation of TiHAP@g-C_(3)N_(4) Heterojunction and Photocatalytic Degradation of Methyl Orange

作　　者：伍林 胡明蕾 王丽萍[1] 黄少萌 周湘远 WU Lin;HU Minglei;WANG Liping;HUANG Shaomeng;ZHOU Xiangyuan(School of Environment and Spatial Informatics,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]中国矿业大学环境与测绘学院,徐州221116

出　　处：《无机材料学报》2023年第5期503-510,I0001,I0002,共10页Journal of Inorganic Materials

基　　金：国家自然科学基金(51974314)。

摘　　要：通过水热法合成了钛羟基磷灰石(TiHAP)与g-C_(3)N_(4)复合光催化剂(TiHAP@g-C_(3)N_(4)),并对其结构和光学特性进行表征,通过甲基橙(MO)降解实验评价其光催化活性。结果表明:样品中短棒状TiHAP生长在g-C_(3)N_(4)表面,均保持原有晶型和化学结构;制备的TiHAP@g-C_(3)N_(4)纯度高,比表面积达107.92 m^(2)/g,较TiHAP、g-C_(3)N_(4)分别增大约135%、44%;在TiHAP@g-C_(3)N_(4)添加量为1.0 g/L、pH 7条件下,120 min内MO降解率达96.35%;3次循环实验降解率保持在80.02%以上,TiHAP@g-C_(3)N_(4)光催化性能良好且结构稳定。空穴(h^(+))在MO降解过程中作用最大,·O_(2)^(–)与·OH的作用递减。TiHAP@g-C_(3)N_(4)异质结的构建,增强了对光的吸收,提高了光生电子-h^(+)的分离效率,保留了氧化还原性更强的TiHAP价带h^(+)和g-C_(3)N_(4)导带电子,从而提升了光催化性能。A composite photocatalyst(TiHAP@g-C_(3)N_(4))consisting of Ti doped hydroxyapatite and g-C_(3)N_(4) was synthesized through hydrothermal route.Its structure and optical property were characterized by various means and photocatalytic activity was evaluated through methyl orange(MO)degradation experiments.Results show that short rod-shaped TiHAP in the sample grows on the surface of g-C_(3)N_(4).Both TiHAP and g-C_(3)N_(4) maintain their original crystal shape and chemical structure.As-prepared TiHAP@g-C_(3)N_(4) is of high purity with specific surface area of 107.92 m^(2)/g,which is increased about 135%and 44%as compared with sole TiHAP and sole g-C_(3)N_(4),respectively.The highest MO degradation rate of 96.35%is achieved within 120 min by TiHAP@g-C_(3)N_(4) at the concentration of 1.0 g/L and pH 7.More than 80.02%of MO was removed in every of three cyclic tests,demonstrating good and stable photocatalytic performance of TiHAP@g-C_(3)N_(4).Holes(h^(+))play the largest role in the MO degradation process,-followed by•O_(2) and•OH.The constructed TiHAP@g-C_(3)N_(4) heterojunction enhances light absorption,improves separation efficiency of photoelectrons-h^(+),and preserves more redox-prone TiHAP valence band h^(+)and g-C_(3)N_(4) conduction band electrons.Therefore,as-synthesized TiHAP@g-C_(3)N_(4) can be a promising catalyst in photocatalytic degradation.

关 键 词：紫外光催化 TiHAP@g-C_(3)N_(4) 甲基橙 异质结 光生电子-空穴 

分 类 号：X522[环境科学与工程—环境工程]