The solution chemistry and reactivity of lacunary Keggin silicotungstates monitored in real-time by a combination of mass spectrometry and electrochemistry.
The solution chemistry of a series of mono-, di- and trilacunary Keggin silicotungstates was investigated by electrospray ionization mass spectrometry (ESI-MS) and general electrospray features especially for lacunary POMs are summarized. The reactions of vanadium incorporation into the lacunary structures were successfully monitored in real-time by a combination of ESI-MS and differential pulse voltammetry (DPV). It was found that all the reactions took place instantaneously and that a subtle speciation change occurred at prolonged reaction times for the pair of reactants, monovacant silicotungstate and sodium metavanadate, suggesting a conversion of mono- to divanadium substituted derivatives. This was shown to result from a solution process, not an ESI-induced reaction, by DPV measurements. The relative stabilities of the V-substituted products were assessed in both solution and gas phases.
Key Laboratory of Cluster Science, Ministry of Education of China, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry, Beijing Institute of Technology, Beijing 100081, People's Republic of China. jcao@bit.edu.cn cwhu@bit.edu.cn.
Qiaodi
Q
Jia
Jie
J
Cao
Yunpeng
Y
Duan
Changwen
C
Hu