98%
921
2 minutes
20
Long-persistent luminescence (LPL) materials have applications from safety signage to bioimaging; however, existing organic LPL (OLPL) systems do not align with human scotopic vision, which is sensitive to blue light. We present a strategy to blueshift the emissions in binary OLPL systems by upconverting the charge-transfer (CT) to a locally excited (LE) singlet state. Through rigorous steady-state and time-resolved photoluminescence spectroscopy and wavelength-resolved thermoluminescence measurements, we provide the direct experimental evidence for this upconversion in OLPL systems featuring small energy offsets between the lowest-energy CT and LE singlet states. These systems exhibited strong room temperature LPL, particularly when extrinsic electron traps are added. Importantly, the developed OLPL system achieved Class A (ISO 17398) LPL, matching well with human scotopic vision. The findings not only elucidate the role of small energy offsets in modulating LPL but also provide potential avenues for enhancing the efficiency and applicability of OLPL materials.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11920369 | PMC |
http://dx.doi.org/10.1038/s41467-025-58048-2 | DOI Listing |
Adv Sci (Weinh)
June 2025
State Key Laboratory of Organometallic Chemistry and Shanghai Hongkong Joint Laboratory in Chemical Synthesis, Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules, Ningbo Zhongke Creation Center of New Materials, Shanghai Institute of Organic Chemistry, Universit
Organic long persistent luminescence (OLPL) materials feature power law emission decay and minutes-/hours-long afterglow durations because of retarded charge recombination. Unlike conventional room-temperature phosphorescence (RTP) and thermally activated delayed fluorescence (TADF) afterglow, the emergence of OLPL must include a charge separation process in its photophysical mechanism; consequently, the reported OLPL examples are much fewer than conventional afterglow materials. The incorporation of an electron donor or acceptor is conceived to interact with the long-lived excited state in conventional afterglow system, aiming to induce charge separation.
View Article and Find Full Text PDFAdv Mater
May 2025
State Key Laboratory of Flexible Electronics (LoFE) & Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, 9 Wenyuan Road, Nanjing, 210023, China.
Circularly polarized organic long persistent luminescence (CP-OLPL) has garnered significant attention due to its distinctive properties. However, achieving CP-OLPL materials with ultralong durations remains a formidable challenge. Herein, an effective strategy is proposed to obtain long-lived CP-OLPL by constructing a self-designed chiral donor for developing a host-guest chiral exciplex system.
View Article and Find Full Text PDFNat Commun
March 2025
Organic Optoelectronics Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa, 904-0495, Japan.
Long-persistent luminescence (LPL) materials have applications from safety signage to bioimaging; however, existing organic LPL (OLPL) systems do not align with human scotopic vision, which is sensitive to blue light. We present a strategy to blueshift the emissions in binary OLPL systems by upconverting the charge-transfer (CT) to a locally excited (LE) singlet state. Through rigorous steady-state and time-resolved photoluminescence spectroscopy and wavelength-resolved thermoluminescence measurements, we provide the direct experimental evidence for this upconversion in OLPL systems featuring small energy offsets between the lowest-energy CT and LE singlet states.
View Article and Find Full Text PDFAdv Sci (Weinh)
April 2025
State Key Laboratory of Organometallic Chemistry, Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, P. R. Chin
Organic long persistent luminescence (OLPL) materials, with their hour-long afterglow, hold great promise across numerous applications, yet their performance lags behind that of inorganic counterparts. A deeper understanding of the underlying photophysical mechanisms, particularly the effective control of radical intermediates, is essential for developing high-performance OLPL materials; while systematic studies on the intrinsic stability of radical intermediates and their impact on OLPL performance remain scarce. Here biphenyl groups is introduced into a luminophore-matrix-donor three-component OLPL system.
View Article and Find Full Text PDFChem Sci
August 2024
State Key Laboratory of Organic Electronics and Information Displays, Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications 9 Wenyuan Road Nanjing 210023 China
Developing exciplex-based organic long-persistent luminescence (OLPL) materials with high stability is very important but remains a formidable challenge in a single-component system. Here, we report a facile strategy to achieve highly stable OLPL in an amorphous exciplex copolymer system through-space charge transfer (TSCT). The copolymer composed of electron donor and acceptor units can not only exhibit effective TSCT for intra/intermolecular exciplex emission but also construct a rigid environment to isolate oxygen and suppress non-radiative decay, thereby enabling stable exciplex-based OLPL emission with color-tunable feature for more than 100 h under ambient conditions.
View Article and Find Full Text PDF