Preparation and Properties of Transparent Ultrathin Lanthanide‐Complex Films

Highly transparent ultrathin films (UTFs) based on alternative layer‐by‐layer assembly of Eu‐ and Tb‐based lanthanide complexes (LCs) and Mg–Al‐layered double hydroxide (LDH) nanosheets are reported herein. UV–visible absorption and fluorescence spectroscopy showed an orderly growth of the two types of ultrathin films upon increasing the number of deposition cycles. AFM and SEM measurements indicate that the films feature periodic layered structures as well as uniform surface morphology. Luminescent investigations reveal that (LCs/LDH)_n UTFs can detect Fe³⁺ with relative selectivity and high sensitivity (Stern–Volmer constant K_SV=8.43×10³ L mol^?1); this suggests that (LCs/LDH)_n UTFs could be a promising luminescent probe for selectively sensing Fe³⁺ ion.