Single-Source Alkoxide Precursor Approach to Titanium Molybdate, TiMoO₅, and Its Structure, Electrochemical Properties, and Potential as an Anode Material for Alkali Metal Ion Batteries

Abstract

Transition-metal oxide nanostructured materials are potentially attractive alternatives as anodes for Li ion batteries and as photocatalysts. Combining the structural and thermal stability of titanium oxides with the relatively high oxidation potential and charge capacity of molybdenum(VI) oxides was the motivation for a search for approaches to mixed oxides of these two metals. Challenges in traditional synthetic methods for such materials made development of a soft chemistry single-source precursor pathway our priority. A series of bimetallic Ti-Mo alkoxides were produced by reactions of homometallic species in a 1:1 ratio. Thermal solution reduction with subsequent reoxidation by dry air offered in minor yields Ti 2 Mo 2 O 4 (OMe) 6 (O i Pr) 6 ( 1 ) by the interaction of Ti(O i Pr) 4 with MoO(OMe) 4 and Ti 6 Mo 6 O 22 (O i Pr) 16 (iPrOH) 2 ( 2 ) by the reaction of Ti(O i Pr) 4 with MoO(O i Pr) 4 . An attempt to improve the yield of 2 by microhydrolysis, using the addition of stoichiometric amounts of water, resulted in the formation with high yield of a different complex, Mo 7 Ti 7+ x O 31+ x (O i Pr) 8+2 x ( 3 ). Controlled thermal decomposition of 1 – 3 in air resulted in their transformation into the phase TiMoO 5 ( 4 ) with an orthorhombic structure in space group Pnma , as determined by a Rietveld refinement. The electrochemical characteristics of 4 and its chemical transformation on Li insertion were investigated, showing its potential as a promising anode material for Li ion batteries for the first time. A lower charge capacity and lower stability were observed for its application as an anode for a Na ion battery.

Conjugated Porous Polydiaminophenylsulfone–Triazine Polymer—A High-Performance Anode for Li-Ion Batteries

“…28,51 Meanwhile, Figure 4f shows the charge−discharge curve of rate performance, which displays similar plateaus at different current densities, further suggesting outstanding reversibility and stability of PST. PST exhibits good electrochemical performance, which is better than some reported organic-/inorganic-based anodes for LIBs (Figure 4g), such as TiMoO 5 , 52 Li 4 C 8 H 2 O 6 , 53 N-doped graphene, 54 and ellagic acid. 55 Subsequently, EIS was used to analyze the electrochemical performance of PST.…”

“…The good rate capability could be ascribed to the conjugated and porous structure of PST, which is favorable for the transportation of electrons and ions. , Meanwhile, Figure f shows the charge–discharge curve of rate performance, which displays similar plateaus at different current densities, further suggesting outstanding reversibility and stability of PST. PST exhibits good electrochemical performance, which is better than some reported organic-/inorganic-based anodes for LIBs (Figure g), such as TiMoO 5 , Li 4 C 8 H 2 O 6 , N-doped graphene, and ellagic acid …”

Structural diversity in transition metal-doped titanium oxo-alkoxy complexes: Potential sol-gel intermediates for doped titania nanoparticles and complex titanates

“…Several successful efforts to synthesize single-source precursors for bimetallic titanates have been reported including cobalt titanate [24], titanium molybdate [25], and zirconium titanate [26]. Furthermore, additional organic ligands in the SSPs can facilitate formation of highly porous materials due to gas evolution during combustion/calcination [27] and also increase volatiliy for application in chemical vapor deposition (CVD) of complex oxides [28].…”