Characterization of polyoxometalates by electrospray ionization mass spectrometry  

作　　者：Qiaodi Jia Yan Zhang Jie Cao 

机构地区：[1]Key Laboratory of Cluster Science,Ministry of Education of China [2]Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials [3]School of Chemistry,Beijing Institute of Technology

出　　处：《Science China Chemistry》2015年第7期1206-1210,共5页中国科学（化学英文版）

基　　金：financially supported by the National Natural Science Foundation of China(21371025);the 111 Project(B07012);a Fundamental Research Grant(20121942006)by the Beijing Institute of Technology

摘　　要：The electrospray behaviors of saturated, substituted, and lacunary polyoxometalates （POMs） with classic Keggin and Dawson structures were investigated systematically by electrospray mass spectrometry （ESI-MS）. The anions included Keggin [SiW12O40]4-, [SiW11O39]8-, [SiW10O36]8 , [SiW9O34]10-, Dawson [P2W18O62]6-, [P2W17O61]10-, and metal-substituted Keggin derivatives such as [PW11MnO40]7-, [SiW10V2O40]6-, and [GeWgCu3O37]10-. Common species observed in the mass spectra arose from the protonation or cationization of either intact or dehydrated precursor ions. Compared to saturated and substituted POMs, lacunary POMs exhibited distinguished MS behaviors such as a much higher degree of cationization and dehydration of the bare polyoxoanions present in the mass spectra. In addition, some of these lacunary POMs were found to undergo subtle speciation change in solution. Freshly prepared solutions are suggested for synthetics for which lacunary POMs are starting materials. The advantages of the cation-exchange process which are prior to MS analysis are illustrated by an example.The electrospray behaviors of saturated, substituted, and lacunary polyoxometalates(POMs) with classic Keggin and Dawson structures were investigated systematically by electrospray mass spectrometry(ESI-MS). The anions included Keggin [Si W12O40]4-, [Si W11O39]8-, [Si W10O36]8-, [Si W9O34]10-, Dawson [P2W18O62]6-, [P2W17O61]10-, and metal-substituted Keggin derivatives such as [PW11Mn O40]7-, [Si W10V2O40]6-, and [Ge W9Cu3O37]10-. Common species observed in the mass spectra arose from the protonation or cationization of either intact or dehydrated precursor ions. Compared to saturated and substituted POMs, lacunary POMs exhibited distinguished MS behaviors such as a much higher degree of cationization and dehydration of the bare polyoxoanions present in the mass spectra. In addition, some of these lacunary POMs were found to undergo subtle speciation change in solution. Freshly prepared solutions are suggested for synthetics for which lacunary POMs are starting materials. The advantages of the cation-exchange process which are prior to MS analysis are illustrated by an example.

关 键 词：saturated SUBSTITUTED and lacunary POMs electrospray ionization mass spectrometry cation-ion exchange process 

分 类 号：O657.63[理学—分析化学]