以PEG为模板剂制备Bi_2O_2CO_3及其可见光光催化性能

Preparation and photocatalytic properties of PEG-Bi_2O_2CO_3 under visible light irradiation

以聚乙二醇-6000(PEG-6000)为模板剂水热法制备碳酸氧铋(p-Bi2O2CO3)粉末,采用X射线衍射(XRD)、扫描电镜(SEM)、X射线光电子能谱(XPS)、透射电子显微镜(TEM)和紫外可见漫反射(DRS)对粉末进行了初步表征。在可见光(λ≥420 nm)照射下,以罗丹明B(RhB)和水杨酸(SA)光催化降解实验为探针反应,实验结果表明,p-Bi2O2CO3具有较高的光催化活性,对RhB和SA有较好的降解效果。通过紫外-可见光谱(UV-Vis)、红外光谱(IR)和测定总有机碳(TOC)含量,光催化反应35 h后RhB的矿化率为77%,同时对SA的降解率达到43%。同时,采用N,N-二乙基对苯二胺(DPD)分光光度法和对苯二甲酸荧光光度法分别测定了降解过程中H2O2和羟基自由基(·OH)的变化,表明p-Bi2O2CO3/Vis光催化降解机理涉及到·OH历程。

Bismuthyl carbonate （p-Bi2O2CO3） powders were synthesized by hydro-thermal method using polyethylene glycol-6000 （PEG-6000） as the template. X-ray diffraction （XRD） , scanning electron microscopy （SEM） , X-ray photoelectron spectroscopy （XPS） , transmission electron microscopy （ TEM ） and UV-visible dif- fuse reflectance （DRS） were employed to characterize the powders. Under visible light （λ≥420nm） irradia- tion,the degradation of rhodamine B （RhB） and salicylic acid （SA） were used as probe reactions to investigate the catalytic performance of Bi2 O2 CO3 modified by PEG-6000 （p-Bi2 O2 CO3 ）. By analyzing the results of ultravi- olet-visible spectroscopy （UV-Vis） , infrared spectroscopy （IR） and total organic carbon （TOC）, the mineraliza- tion rate of RhB was 77% and the degradation rate of SA reached 43%. In addition,the concentration of hydro- gen peroxide （H2O2） and hydroxyl radical （ · OH） were determined by the N, N-diethyl-p-phenylenediamine （DPD） method and the fluorescence method, respectively, and the results demonstrated that the degradation of organic pollutants by p-Bi202CO3 under visible light illumination was dominated by · OH generated in the sys- tem.