Broad-temperature-range thermoresponse of Cu(I)-based organic-inorganic hybrid metal halides with multimode dynamic luminescence

Organic-inorganic hybrid metal halides (OIMHs) based on Cu(I) ions show broad application prospects in the field of stimulus-responsive luminescent materials based on their rich structural diversity and highly adjustable electronic state. However, achieving sensitive and broad-temperature-range thermal responses for OIMHs remains a significant challenge, despite the growing interest in smart luminescence materials. In this study, 4-morpholinopiperidine (4-MP) and CuI are used to synthesize a zero-dimensional warm white-light emitting OIMH, namely MPC-W ((C 9 H 20 N 2 O) 4 (Cu 2 I 4 )(Cu 2 I 6 )(H 2 PO 2 ) 2 ), which features hybrid structures of [Cu 2 I 4 ] 2− and [Cu 2 I 6 ] 4− . Owing to the coexistence of three luminescent mechanisms-organic cluster luminescence (CL), self-trapped exciton (STE) emission of [Cu 2 I 6 ] 4− , and cluster-centered (CC) state luminescence of [Cu 2 I 4 ] 2− , MPC-W exhibits temperature and excitation wavelength-dependent dynamic luminescence. When the temperature is increased from 77 to 297 K, the luminescence color of MPC-W can be continuously tuned from blue to cyan, green, yellow-green, and white. In the range of 217–463 K, MPC-W displays an abnormal luminescence enhancement phenomenon with increasing temperature. Additionally, upon chemical stimulus, MPC-W can reversibly transform into a blue-light emitting crystal named MPC-B ((C 9 H 20 N 2 O)Cu 2 I 4 ), and a yellow-light emitting crystal named MPC-Y ((C 9 H 18 N 2 O) 7 Cu 8 I 8 ). These unique dynamic luminescent properties endow MPC-W with great application potential in temperature sensing, optical anti-counterfeiting, and password locks. The work provides a new insight for the development of novel wide temperature-responsive multifunctional intelligent luminescent materials. The alternative text for this image may have been generated using AI.