Enhanced Superconductivity in Rock-Salt TiO

[Image: see text] Oxygen stoichiometry is critical for physical properties, but it is hard to precisely control in many multivalent transition metal oxides, for example, cuprate superconductors, magnetoresistive manganite oxides, and TiO(x) (x < 2). We have developed a new method to synthesize rock-salt TiO in a sealed and evacuated quartz tube by using KClO(4) as the only oxygen source to react with elemental Ti (in a Ti/O molar ratio of 1:1). The stoichiometric titanium monoxide (TiO) exhibits an enhanced superconductivity transition temperature (T(c)) of 5.5 K, which is superior to the reported results of 0.5–2.3 K. The new synthetic method provides an excellent way to prepare stoichiometric oxides, and the enhanced superconductivity of TiO may initialize the restudy of the transport properties of Ti-containing oxides.