钛取代的Keggin型钨磷酸银微晶的形貌调控及光催化性能  

Morphology Modulation and Photocatalytic Performance of Microcrystal of Silver Salt of Ti-substituted Keggin-type Polyoxotungstate

作　　者：韩宁 谢瑞红 王雪娜[1] 刘术侠[1] HAN Ning;XIE Ruihong;WANG Xuena;LIU Shuxia(Key Laboratory of Polyoxometalate Science of Ministry of Education, College of Chemistry, Northeast Normal University, Changchun 130024, China;College of Chemistry, Jilin University, Changchun 130012, China)

机构地区：[1]东北师范大学化学学院多酸科学教育部重点实验室,长春130024 [2]吉林大学化学学院,长春130012

出　　处：《高等学校化学学报》2018年第7期1378-1383,共6页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:21671023;21371029)资助~~

摘　　要：以聚乙烯吡咯烷酮(PVP)为形貌调节剂,钛取代的Keggin型钨磷酸钾(K_4H_3PTi_2W_(10)O_(40))及硝酸银为前驱体,通过控制PVP用量制备了不同形貌及尺寸的钛取代Keggin型钨磷酸银(Ag4H3PTi2W10O40,AgPTiW).通过分光光度法测定了AgPTiW饱和溶液中Ag^+浓度,并求得其溶度积,利用能斯特(Nernst)方程求出Ag_4H_3PTi_2W_(10)O_(40)/Ag电对的标准电极电势,由此确定了Ag_4H_3PTi_2W_(10)O_(40)作为光催化剂的导带能级位置.通过红外光谱、粉末XRD谱图及紫外-可见光谱等测试手段对不同形貌AgPTiW的组成、结构和光吸收性质进行了表征;研究了可见光区(λ>400 nm)不同形貌AgPTiW对染料甲基橙(MO)的光催化降解活性.研究发现,丝状AgPTiW在可见光下催化降解MO的活性优于棒状和柱状AgPTiW,推测这可能与纳米丝状催化剂较大的长径比及比表面积有关.Silver salts of Ti-substituted Keggin-type polyoxotungstate（ Ag4H3PTi2W10O40,AgPTiW） with different morphologies and sizes were synthesized with potassium dititanodecatungsto-phosphate and silver nitrate as precursors,polyvinylpyrrolidone with various dosage as morphology modulator. The concentration of Ag＋in saturated solution of AgPTiW was measured by spectrophometric method,and its solubility product was then obtained. Furthermore,the standard electrode potential of Ag4H3PTi2W10O40/Ag was calculated by Nernst equation, and thus the conduction band of AgPTiW was located. Crystal structures and optical absorption properties of AgPTiW with different morphologies were characterized by infrared spectra（ FTIR）,powder XRD analysis and UV-Vis diffuse reflectance spectra. Photocatalytic degradation of methyl orange tests were carried out over AgPTiW with different morphologies under visible-light irradiation（ λ〉400 nm）. The results showed that the visible-light catalytic activity of AgPTiW with nanowire shape was better than that with rod or columnar morphology. It might be related to the highest aspect ratio and the highest specific surface area of nanowire catalyst.

关 键 词：Keggin型钨磷酸 银盐 钛取代 形貌调控 光催化 

分 类 号：O614[理学—无机化学]