The inner filter effect of Cr(VI) on Tb-doped layered rare earth hydroxychlorides: new fluorescent adsorbents for the simple detection of Cr(VI).

Terbium-doped layered yttrium hydroxychlorides (LYH:xTb) were explored for the simple and convenient detection of Cr(VI) in aqueous solution, where the effective overlap of excitation bands of LYH:xTb with absorption bands of Cr(VI) constructs a new inner filter effect system. The shielding of excitation light for LYH:xTb by adsorbed Cr(VI) was so effective that a feasible detection sensitivity could be achieved.