Vanadyl sulfates: molecular structure, magnetism and electrochemical activity

Anna Ignaszak, Nigel Patterson, Mariusz Radtke, Mark R. J. Elsegood, Josef W. A. Frese, Joah L. Z. F. Lipman, Takehiko Yamato, Sergio Sanz, Euan K. Brechin, Timothy J. Prior, Carl Redshaw

Research output: Contribution to journalArticlepeer-review

Abstract

Reaction of differing amounts of vanadyl sulfate with p-tert-butylthiacalix[4]areneH(4) and base allows access to the vanadyl-sulfate species [NEt4](4)[(VO)(4)((3)-OH)(4)(SO4)(4)] 1/2H(2)O (1), [HNEt3](5)[(VO)(5)((3)-O)(4)(SO4)(4)] 4MeCN (2 4MeCN) and [NEt4](2)[(VO)(6)(O)(2)(SO4)(4)(OMe)(OH2)] MeCN (3 MeCN ). Similar use of p-tert-butylsulfonylcalix[4]areneH(4), p-tert-butylcalix[8]areneH(8) or p-tert-butylhexahomotrioxacalix[3]areneH(3) led to the isolation of [HNEt3](2)[H2NEt2](2){[VO(OMe)](2)p-tert-butylcalix[8-SO2]areneH(2)} (4), [HNEt3](2)[V(O)(2)p-tert-butylcalix[8]areneH(5)] (5) and [HNEt3](2)[VIV2VV4O(11)(OMe)(8)] (6), respectively. Dc magnetic susceptibility measurements were performed on powdered microcrystalline samples of 1-3 in the T = 300-2 K temperature range. Preliminary screening for electrochemical water oxidation revealed some activity for 2 with turnover frequency (TOF) and number (TON) of 2.2 x 10(-4) s(-1) and 6.44 x 10(-6) (mmol O-2/mmol cat.), respectively. The compound 3 showed an improved electrochemical activity in the presence of water. This is related to the increased number and the rate of electrons exchanged during oxidation of V4+ species, facilitated by protons generated in the water discharge process.

Original languageEnglish
Pages (from-to)15983-15993
Number of pages11
JournalDalton Transactions
Volume47
Issue number44
Early online date22 Oct 2018
DOIs
Publication statusPublished - 28 Nov 2018

Keywords

  • ALKOXIDE ANION CLUSTERS
  • CRYSTAL-STRUCTURE
  • WATER OXIDATION
  • COMPLEX
  • OXOVANADIUM
  • CHEMISTRY
  • MODELS
  • CORE
  • OXO
  • CALIXARENES

Fingerprint Dive into the research topics of 'Vanadyl sulfates: molecular structure, magnetism and electrochemical activity'. Together they form a unique fingerprint.

Cite this