Orange/cyan emissive sensors of Sb3+ for probing water via reversible phase transformation in rare-earth-based perovskite crystals

A new strategy to probe water content based on orange/cyan emissive sensors of Sb 3+ through the reversible phase transformation between Rb 2 ScCl 5 ·H 2 O and Rb 3 ScCl 6 is developed. In-depth analysis suggests that the luminescence of Sb 3+ in the two crystals originates from STEs.