The Deep Eutectic Solvent Precipitation Synthesis of Metastable Zn4V2O9

• DOI: 10.1021/acs.inorgchem.1c02511
• Publication Date: 2021-12-13T23:31:51Z
• Authors: Sangki Hong; Ye Cheng; Shruti Hariyani; Jingzhe Li; Rachel M. Doughty; Aishwarya Mantravadi; Adedoyin N. Adeyemi; Emily A. Smith; Jakoah Brgoch; Frank E. Osterloh; Julia V. Zaikina
• Keywords: Vanadate; Metastability; Deep eutectic solvent

A precipitation method involving a deep eutectic solvent (DES)─a mixture of hydrogen bond donor and acceptor─is used to synthesize ternary metal oxide. Without toxic reagents, precipitates consisting Zn3(OH)2V2O7·nH2O Zn5(OH)6(CO3)2 are obtained by simply introducing deionized H2O the DES solution containing dissolved ZnO V2O5. Manipulation synthetic conditions demonstrates high tunability in size/morphology two-dimensional nanosheets precipitated during dynamic equilibrium process. According differential scanning calorimetry high-temperature powder X-ray diffraction, Zn3V2O8 annealing precipitate intermediates reaction pathway toward metastable Zn4V2O9. Intimate mixing precursors achieved allows access zinc-rich vanadate with unusually rapid heat treatment. The UV-vis surface photovoltage spectra reveal presence sub-band gap states, stemming from reduced vanadium (V4+) center. Photoelectrochemical measurements confirm weak photoanodic currents for water methanol oxidation. For first time, this work shows synthesis oxide DES-precipitation route provides insight into structure-property relationship vanadate.