Zn–M–Cr三元类水滑石的合成及其光催化性能  

Synthesis and Photocatalytic Activity of Zn–M–Cr Hydrotalcite-like Compounds

作　　者：徐敏虹[1] 潘国祥[1] 汪小华[2] 陈海锋[1] 伍涛[1] 郭玉华[1] 

机构地区：[1]湖州师范学院工学院材料工程系,浙江湖州313000 [2]同济大学浙江学院,浙江嘉兴314001

出　　处：《硅酸盐学报》2017年第8期1175-1182,共8页Journal of The Chinese Ceramic Society

基　　金：浙江省自然科学基金(LY17E040001);国家社会科学基金特别委托项目(16@ZH005)资助

摘　　要：采用共沉淀法制备CO_3^(2–)为层间阴离子的Zn–M–Cr–CO_3–HTLCS(类水滑石)三元类水滑石样品,Zn^(2+)、M^(2+)、Cr^(3+)摩尔比为1.5︰1.5︰1.0,M=Mg、Mn、Co、Ni、Cu。用X射线衍射、红外光谱、热重–差热分析和紫外–可见漫反射光谱等分析技术对三元类水滑石的结构和性质进行表征。结果表明:不同二价金属阳离子取代的5种三元类水滑石都具有水滑石的典型层状结构。取代二价金属阳离子半径越小,晶胞参数a值也越小,三元水滑石热稳定性越好。考察了光照时间和催化剂种类、用量等因素对三元类水滑石光催化降解罗丹明B(RhB)溶液的影响,讨论了光催化降解RhB的反应机理。结果表明:Zn–Ni–Cr–CO_3–HTLCS的光催化性能最好,其用量为0.1 g/50 mL条件下,光照120 min,RhB的降解率达到90.72%,循环使用4次后,对RhB的降解率保持在90%左右,且催化剂晶体结构不变。Carbonate pillared hydrotalcite-like compounds of Zn-M-Cr-CO3-HTLCS（hydrotalcite-like compounds） （Zn2＋/M2＋/Cr3＋ atomic ratio of 1.5： 1.5： 1.0 and M： Mg, Mn, Co, Ni, Cu） were synthesized by a co-precipitation method. The structures and properties of Zn-M-Cr-CO3-HTLCS were characterized by X-ray diffraction （XRD）, Fourier transform infrared spectrometry （FT-IR）, thermogravimetry analysis-differential scanning calorimetry （TG-DTA） and UV-visible diffuse-reflectance spectroscopy （UV-Vis DRS）, respectively. Based on the XRD and FT-IR analysis, five kinds of different cationic substituted Zn-M-Cr--CO3-HTLCS have a typical layered structure of layered double hydroxides intercalated with carbonate. The value of lattice parameter a decreases, but the thermal stability of hydrotalcite increases at the smaller ionic radius of substituted divalent metallic cations. The photocatalytic activities of Zn-M-Cr-CO3-HTLCS were examined with Rhodamine B （RhB） and the photodegradation mechanism was also discussed. The results show that the optimum photocatalytic performance of Zn-Ni-Cr-CO3-HTLCS can be obtained. The degradation rate of the Zn-Ni-Cr-CO3-HTLCS for RhB under the light irradiation for 2 h is 90.72% when the dosage of Zn-Ni--Cr-CO3-HTLCS is 0.1 g/50 mL, and is still 90% after reused for four times.

关 键 词：类水滑石 共沉淀法 光催化 罗丹明B 

分 类 号：O643[理学—物理化学]