# Synthesis, Structure, and Photocatalysis in a New Structural Variant of the Aurivillius Phase: $LiBi_4M_3O_{14}$ (M = Nb, Ta)

Muktha, B and Priya, MH and Madras, Giridhar and Row, Guru TN (2005) Synthesis, Structure, and Photocatalysis in a New Structural Variant of the Aurivillius Phase: $LiBi_4M_3O_{14}$ (M = Nb, Ta). In: Journal of Physical Chemistry B, 109 (23). pp. 11442-11449.

 PDF Synthesis,_Structure,_and_Photocatalysis_in_a_New_Structural.pdf Restricted to Registered users only Download (244Kb) | Request a copy

## Abstract

Two new compounds, $LiBi_4Nb_3O_1_4$ and $LiBi_4Ta_3O_1_4$, have been synthesized by the solid-state method, using $Li_2CO_3$, $Bi_2O_3$, and $M_2O_5$ (M = Nb, Ta) in stoichiometric quantities. These compounds crystallize in the monoclinic C2/c space group with a=13.035(3)\AA, b=7.647(2)\AA, c=12.217(3)\AA, $\beta=101.512(4)^0$, $V=1193.4(5)\AA^3$ , and Z=4 and $a=13.016(2)\AA$, $b=7.583(1)\AA$, $c=12.226(2)\AA$, $\beta=101.477(3)^0$, $V=1182.6(5)\AA^3$, and Z=4, respectively. These are isostructural and the structure along the b axis consists of layers of $[Bi_2O_2]^2^+$ units separated by layers of $LiO_4$ tetrahedra and $NbO_6$ octahedra hence depicting an unusual variation in the Aurivillius phase isolated for the first time. The presence of lithium has been confirmed by $^7Li$ NMR studies. ac impedance measurements and variable temperature $^7Li$ NMR studies indicate oxygen ion conductivity in these materials. The UV-visible spectra suggest a band gap of 3.0 eV for $LiBi_4Nb_3O_1_4$ and 3.5 eV for $LiBi_4Ta_3O_1_4$, respectively, and the associated studies on degradation of dyes and phenols render these materials suitable for photocatalysis.

Item Type: Journal Article Copyright of this article belongs to American Chemical Society. Division of Chemical Sciences > Solid State & Structural Chemistry UnitDivision of Mechanical Sciences > Chemical Engineering 16 May 2007 19 Sep 2010 04:35 http://eprints.iisc.ernet.in/id/eprint/9751