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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.
The electrochemical properties and redox properties of polyoxometallate (POM) / SBA-15 mesoporous hybrid materials synthesized by co-condensation method and secondary grafting method were investigated by cyclic voltammetry and carbon paste electrode. Acetonitrile medium and the detected potential range, the free PW1 1 Si 32-species in solution and the same POM species impregnated on mesoporous silica show two pairs of WVI single electron redox peaks; covalent bonding to mesoporous The PW1 1 Si 32-species on silica also showed two pairs of peaks, but the peak current of the first peak increased and the reduction potential shifted positively relative to the impregnated sample, indicating that the covalently bonded POM not only retained its original oxidation Reduction performance, but also stronger oxidation than the POM impregnated with the load.The relationship between the peak flow and the sweep rate shows that the sample redox process is surface-controlled at low sweep rates and diffused at high sweep rates In addition, tungstophosphate samples are more oxidative than tungstosilicate samples and samples synthesized by co-condensation and second-grafting methods have similar electrochemical behavior.