Multicolor luminescence of supramolecular compounds based on mixed Dy–lanthanide complexes and cucurbit[6]uril for logic gate operation and WLED application

Abstract

The supramolecular approach was used to produce supramolecular assemblies exhibiting multicolor emission. Aquanitrato complexes of di- (1–8) and tri- (9–12) component lanthanides were obtained as supramolecular compounds with the organic macrocyclic cavitand cucurbit[6]uril as crystals. The X-ray diffraction study demonstrated that these compounds have the following compositions: 1–8 [{Ln¹_mLn²_n(H₂O)₅(NO₃)}₂CB[6]](NO₃)₄·HNO₃·xH₂O (Ln¹ = Dy; Ln² = Pr(1), Nd(2), Sm(3), Gd(4), Tb(5), and Ho(6)), and 2[Ln¹_mLn²_n(H₂O)₈] (NO₃)₃·CB[6]·2HNO₃·yH₂O (Ln¹ = Dy; Ln² = Er(7) and Yb(8)); and 9–12 [{Dy_mEu_nTb_k(H₂O)₅(NO₃)}₂CB[6]](NO₃)₄·HNO₃·zH₂O. The luminescent properties of compounds 1–12 were investigated. The color purity of compounds 4, 6, and 11 is very close to zero, so it is well-suited for white-light generation and can be used for WLED applications. A warm white LED device was fabricated by combining the supramolecular compound 4 and a UV LED chip (365 nm) at a voltage of 3.0 V; the CIE, CCT and CP were (0.282; 0.310), 8891 K and 9%, respectively. Based on complex 11, the diagram of logic gate operation is shown. We propose that complexes can be an efficient tool for creating optical logic gates based on tunable luminescence transformation-dependent emission. Benefitting from excitation-dependent emission in one luminescent complex, a new three-input logic gate was obtained. Therefore, not only does this work provide detailed insights into the interesting fields of mixed lanthanide-based compounds and tunable emission, but it also confirms that aquanitrato complexes can be a new platform for constructing smart luminescent systems and multimodal optical logic gates.