V/HT was synthesized as follows. HT (1.0 g) was added to 100 mL of an aqueous VCl 3 solution (4 mM) and then the mixture was stirred at room
temperature for 3 h. The obtained slurry was filtered, washed with deionized water and dried overnight at room temperature in vacuo to yield V/HT (V:
1.9 wt%) as a pale gray powder. |