| 초록 |
10 wt.% and 20 wt.% $Li-TiO_2$ composite powders are synthesized by a sol-gel method using titanium isopropoxide and $Li_2CO_3$ as precursors. The as-received amorphous 10 wt.% $Li-TiO_2$ composite powders crystallize into the anatase-type crystal structure upon calcination at $450^{ circ}C$ , which then changes to the rutile phase at $750^{ circ}C$ . The asreceived 20 wt% $Li-TiO_2$ composite powders, on the other hand, crystallize into the anatase-type structure. As the calcination temperature increases, the anatase $TiO_2$ phase gets transformed to the $LiTiO_2$ phase. The peaks for the samples obtained after calcination at $900^{ circ}C$ mainly exhibit the $LiTiO_2$ and $Li_2TiO_3$ phases. For a comparison of the photocatalytic activity, 10 wt.% and 20 wt.% $Li-TiO_2$ composite powders calcined at $450^{ circ}C$ , $600^{ circ}C$ , and $750^{ circ}C$ are used. The 20 wt.% $Li-TiO_2$ composite powders calcined at $600^{ circ}C$ show excellent efficiency for the removal of methylorange. |
