钴掺杂羟基锆柱撑钛酸盐材料的制备与光催化性能

Preparation and Photocatalytic Property of Co-Doped Hydroxyl–Zr Pillared Titanate

采用剥离-重堆积的方法将聚合羟基锆离子和Co2+混合溶液嵌入到钛酸盐板层间,制得了钴掺杂锆柱撑材料(CZPT),考察了Co对锆柱撑复合材料(简写为ZPT)的形成及其催化活性的影响。利用X-射线衍射(XRD)、扫描/透射电子显微镜(SEM/HR-TEM)、紫外-可见吸收光谱(UV-Vis)和N2吸附等方法对复合材料进行了表征。结果表明,掺入质量分数为5%(1∶20)的Co可以使ZPT样品的介孔和比表面积明显增大。同时,可以抑制体系光生电子与空穴的复合,吸收光波长有明显的红移。CZPT系列柱撑材料在紫外和可见光辐照下催化降解罗丹明(Rh B)的脱色率明显高于ZPT。其中,复合材料CZPT-5的催化活性最好,表明材料的光催化活性还与掺杂后柱撑材料中含Co客体与主体间的电子耦合作用有关。

Mesoporous nanocomposite of Co-doped hydroxyl–Zr-pillared titanate（CZPT） was prepared via an exfoliation- restacking route, and the pre- exfoliated layered titanate was reassembled in an aqueous solution containing hydroxyl–Zr oligocations and Co ions. The influence of the doping Co cations on the preparation and catalytic activity of Zr-pillared titanate（abbreviated as ZPT） composites was investigated. The prepared CZPT was characterized by powder X-ray diffraction, scanning electron microscope, transmission electron microscopy, UV- Vis spectra and porosity measurements. XRD and N_2 absorption results suggested that the ZPT doped with 5% Co（mass fraction） had bigger pore diameter and specific area. The presence of 5% Co could effectively suppress the annihilation of the photogenerated hole-electron pairs, and correspondingly the absorption wavelength exhibits obviously red-shift. The degradation of rhodamine B（Rh B） under ultraviolet and visible radiation shows that the as- prepared nanocomposite exhibits higher photocatalytic activities than that of layered titanate alone. The enhanced photocatalytic activity of the as-prepared nanocomposite CZPT-5 for the degradation of Rh B under visible irradiation may be attributed to the coupling interaction between cations of the host and the Co containing guest.