A single-component white-light-emitting hybrid copper(i) halide constructed using a supramolecular cation for WLEDs

Abstract

Single-component white-light-emitters ensure color stability while reducing device complexity, and are ideal candidates for white light-emitting diodes (WLEDs). However, the realization of single-component white-light emission with high efficiency and stability is still a challenge. Herein, a supramolecular cation strategy was used to synthesize the organic–inorganic hybrid copper(I) halide [(AMTA)(18C6)]₂Cu₂I₄ (1), with AMTA = 1-adamantanamine and 18C6 = 18-crown-6. The structure of 1 comprises a [Cu₂I₄]²⁻ anion, formed from two edge-sharing CuI₃ triangles, and two [(AMTA)(18C6)]⁺ supramolecular cations. Compound 1 exhibits efficient white-light emission featuring dual bands centered at 480 nm and 642 nm. The CIE coordinate (0.32, 0.33) approaches the pure white point (0.33, 0.33), while the quantum yield reaches 62.09%. Such efficient white-light emission arises from two self-trapped exciton (STE) states within the inorganic unit. Furthermore, compound 1 shows remarkable stability, remaining stable for over 90 days in air and for 15 days under 75% humidity conditions. The single-component WLED fabricated using this material achieved a color rendering index (CRI) of 84, meeting the requirement for everyday lighting applications. This study demonstrates a novel approach for engineering single-component white-light phosphors suitable for solid-state lighting applications.