Issue 12, 2024

Tricolour luminescence in an Au(i) complex controlled by polymorphism and mechanical stress

Abstract

The aggregation-induced emission (AIE) behaviour of gold(I) complexes has been extensively reported. In particular, Au complexes that exhibit colour tunability towards changes in aggregated structures are becoming increasingly attractive in the field of materials science. Herein, we report CP, a rod-shaped Au complex with a cyclohexylphenyl moiety and an isocyanide ligand. The photophysical behaviour of CP in various states is discussed based on their primary and aggregated structures. CP emitted room-temperature phosphorescence (RTP) with high-contrast polymorph-dependent colours of blue (CP-B), green (CP-G), and yellow (CP-Y) depending on the recrystallisation conditions. CP-Y, which has the shortest Au–Au distance, exhibits an efficient direct S0–Tn transition, leading to an enhanced RTP quantum yield (ΦRTP) of 38% under S0–Tn excitation. Interestingly, X-ray diffraction analysis revealed that CP-B and CP-G exhibit identical crystal structures despite their distinct emission colours. Photophysical and differential scanning calorimetry analyses revealed that the presence of small crystal domains, such as those in the ground samples of CP, is responsible for the overall green emission observed in bulk CP-G, indicating that the crystal structure and size determine the RTP colour. Moreover, CP also exhibits a liquid-crystalline (LC) nature and mechanochromic luminescence. Our findings demonstrate that the aggregated structure and AIE properties of Au complexes can be effectively controlled through crystalline-to-LC or crystalline-to-crystalline phase transitions of the complexes.

Graphical abstract: Tricolour luminescence in an Au(i) complex controlled by polymorphism and mechanical stress

Supplementary files

Article information

Article type
Paper
Submitted
26 Mar 2024
Accepted
10 May 2024
First published
14 May 2024
This article is Open Access
Creative Commons BY license

Mater. Adv., 2024,5, 5052-5062

Tricolour luminescence in an Au(I) complex controlled by polymorphism and mechanical stress

A. Furoida, M. Daitani, K. Matsumoto, K. Hisano and O. Tsutsumi, Mater. Adv., 2024, 5, 5052 DOI: 10.1039/D4MA00314D

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements