共价键联的多金属氧酸盐/SBA-15介孔杂化材料的电化学性质研究  

Electrochemical Properties of Covalent Bonded Polyoxometalate/SBA-15 Mesoporous Hybrid Materials

作　　者：罗秀娟[1] 杨春[1] 陈煜[1] 

机构地区：[1]江苏省生物功能材料重点实验室南京师范大学化学与材料科学学院,南京210097

出　　处：《化学学报》2011年第1期1-7,共7页Acta Chimica Sinica

基　　金：国家自然科学基金(No.20473037);南京师范大学"211工程"三期重点学科建设计划资助项目

摘　　要：采用循环伏安法和碳糊电极,考察了用共缩合法和二次嫁接法合成的多金属氧酸盐(POM)/SBA-15介孔杂化材料的电化学性质以及氧化还原性能.在乙腈介质和所检测的电势范围内,溶液中游离的PW1 1 Si 32-物种和浸渍负载于介孔氧化硅上的同样POM物种显示两对WVI单电子氧化还原峰;共价键联于介孔氧化硅上的PW1 1 Si 32-物种也显示两对峰,但第一对峰的峰电流增大,还原电位比浸渍样品正移,表明共价键联的POM不仅能够保持其原有的氧化还原性能,而且比浸渍负载的POM具有更强的氧化性.峰流～扫速的关系显示,在低扫速时,样品的氧化还原过程是表面控制的;在高扫速时,则是扩散控制的.另外,钨磷酸盐样品的氧化性大于钨硅酸盐样品;共缩合法和二次嫁接法合成的样品具有相似的电化学行为.Electrochemical behaviors and redox properties of polyoxometalate（POM）/SBA-15 mesoporous hybrid materials,prepared by co-condensation and post-synthesis,were investigated using carbon paste electrodes by cyclic voltammetric measurement.In acetonitrile solution and the range of potentials studied,the cyclic voltammograms of free species in the solution and the same species loaded on mesoporous silica by impregnation showed two one-electron waves corresponding to redox processes of WVI.For the same POM species bonded covalently onto mesoporous silica,however,the current of first wave increased and reduction potentials shifted towards positive direction as compared with the impregnated sample,indicating that these species not only retained the redox property of POM perfectly,but also pos-sessed more intense oxidbillity than the impregnated POM species.The plots of current versus scan rate showed that the redox processes of the hybrid samples were surface-controlled at lower scan rates but diffu-sion-controlled at higher scan rates.It was also found that the oxidbillity of tungstophosphate was higher than that of tungstosilicate;and the similar electrochemical behaviors were presented for the hybrid samples prepared by both routes.

关 键 词：电化学性质 循环伏安法 多金属氧酸盐 SBA-15 介孔杂化材料 

分 类 号：TB34[一般工业技术—材料科学与工程]