Synthesis, microstructural characterization, and electrochemical performance of novel rod-like Ti4O7 powders

- High purity rod-like Ti4O7 powders were successfully fabricated by molten salt synthesis.
- The growth mechanism of the rod-like Ti4O7 powders was proposed, in which two major factors might be involved.
- The electrode material prepared from novel rod-like Ti4O7 powders exhibits high conductivity and great corrosion resistance.

High purity rod-like Ti4O7 powders were successfully fabricated by molten salt synthesis. The phase transformation and the morphology of the as-prepared powders were examined by X-Ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that the Ti4O7 powders obtained by molten salt synthesis exhibited a well-developed rod-like morphology possessing an average length of 15-20 μm and a width of 1-2 μm, of which the reaction mechanism was as well discussed. In addition, the Ti4O7 bulk materials were sintered via spark plasma sintering (SPS). Conductivity of the Ti4O7 bulk materials obtained from the novel rod-like powders (952.4 S/cm) increases by approximately 28.6% and 31% compared with those prepared via conventional method and graphite electrode, respectively. Electrochemical stability measurements show the Ti4O7 bulk sintered from rod-like powders exhibits good corrosion-resistance in acidic solution. The serving life of the electrode approximately is 15 years, in contrast to the 13 years of Ti4O7 electrode prepared from the conventional powders.

222