Crystal growth, thermal, optical, magnetic and electrochemical properties of Mo2Ta2O11
Abdullah Al Muhit, Alevtina A. Maksimova, Sean Wechsler, Habiba Binte Kashem, Gopabandhu Panigrahi, Gregory Morrison, Morgan Stefik, Hans‐Conrad zur Loye
Abstract
Single crystals of the transition metal oxide Mo 2 Ta 2 O 11 were grown for the first time using molten flux synthesis. The compound crystalizes in the trigonal space group R 3 ‾ m (no. 166) with lattice parameters a = b = 5.6267(1) Å and c = 25.1424(6) Å and a unit cell volume of 689.36(3) Å 3 . The structure of Mo 2 Ta 2 O 11 is composed of alternating layers of TaO 6 octahedra and MoO 4 tetrahedra connected via corner-sharing. CaH 2 was used to achieve a partial low temperature reduction of Mo 2 Ta 2 O 11 . The electrochemical lithiation of polycrystalline Mo 2 Ta 2 O 11 was also investigated for the first time. Mo 2 Ta 2 O 11 underwent a structural rearrangement while maintaining a reversible capacity of ∼150 mAh/g. • Mo 2 Ta 2 O 11 was synthesized via molten flux crystal growth yielding high quality single crystals. • Optical investigation reveals the semiconducting nature of the compound. • A low temperature reduction in the compound gave rise to paramagnetic behavior. • Mo 2 Ta 2 O 11 exhibits a reversible lithiation capacity of 167.6 mAh/g, however, accompanied by a loss of structural integrity.