Affiliation:
1. State Key Laboratory of Featured Metal Materials and Life‐cycle Safety for Composite Structures/Key Laboratory of Electrochemical Energy Materials/Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology School of Chemistry and Chemical Engineering Guangxi University Nanning Guangxi 530004 P. R. China
2. Institute of Clean Energy and Materials/Key Laboratory for Clean Energy and Materials School of Chemistry and Chemical Engineering Guangzhou University Guangzhou Guangdong 510006 P. R. China
3. Department of Chemistry and Biochemistry University of California Santa Cruz CA 95064 USA
Abstract
AbstractLead‐free double perovskites with multi‐mode emission characters are highly desired for optoelectronic devices. Herein, dual‐mode thermal responses with low thermal quenching in the red emission channel and high thermal quenching in the near‐infrared (NIR) channel are achieved in a holmium‐based double perovskite (Cs2NaHoCl6). The temperature‐dependent emission is modulated by manipulating three cross relaxations of CR1 (5F4, 5I7) → (5F5, 5I6), CR2 (5S2, 5I8) → (5F5, 5I7), and CR3 (5F5, 5F5) → (5I7, 5G4) through adjusting the concentration of Ho3+. The difference in thermal response between the red and NIR emissions becomes more pronounced with a higher concentration of Ho3+ up to 100%, while the two emissions show almost the same thermal quenching behavior when the Ho3+ concentration is below 20%. To demonstrate their applications, a thermal‐responsive dual‐mode information encryption system and a NIR emitting LED with night vision capacity are fabricated using the prepared samples. This study provides a new approach for thermal quenching regulation in rare‐earth‐based lead‐free perovskites and illustrates their potential in lighting, anti‐counterfeiting, and sensing applications.
Funder
Natural Science Foundation of Guangdong Province
National Natural Science Foundation of China