Stabilization of microcrystal λ-Ti3O5 at room temperature by aluminum-ion doping.

λ-Ti₃O₅ is an intriguing phase-transition material that has been proposed to be metastable and has emerged at room temperature only in the form of nanocrystals. In this work, λ-Ti₃O₅ was stabilized to room temperature in the form of microcrystals by aluminum (Al)-ion doping. Al entered the Ti₃O₅ lattice in the substitutional mode, which reduced the threshold temperature (T_c) of the β-λ phase transition in Ti₃O₅ and maintained a λ-phase Ti₃O₅ at room temperature. Al doping caused a significant decrease in resistivity of Ti₃O₅, which corresponds to a semiconductor-metal transition that is induced by Al-ion doping. We have developed a mechanism to fabricate λ-Ti₃O₅ by ion doping and have provided a fundamental foundation for a more available application of λ-Ti₃O₅ in smart optoelectronic devices. [ABSTRACT FROM AUTHOR]