TY - JOUR
T1 - Substituent-Engineered Spirofluorene-Boron Emitters
T2 - Integrating TADF, Visible Afterglow, and Mechanochromism in a Single Material
AU - Li, Hongbo
AU - Yao, Chunxia
AU - Wang, Zewei
AU - Wang, Nan
AU - Yin, Xiaodong
AU - Qiao, Yali
AU - Liang, Fushun
N1 - Publisher Copyright:
© 2025 American Chemical Society
PY - 2026/1/14
Y1 - 2026/1/14
N2 - A series of spirofluorene–triarylborane derivatives bearing tunable triarylamine donors (–H, –OMe, –SMe) were designed and synthesized to systematically investigate substituent effects on their photophysical behaviors. The methoxy-substituted compound FXylB-DOBPDA exhibits efficient thermally activated delayed fluorescence (TADF), characterized by a small singlet–triplet energy gap (ΔEST) of 0.05 eV, along with notable aggregation-induced emission enhancement (AIEE). Remarkably, through a host–guest doping strategy using triphenylamine (TPA) as the matrix, the system displays clearly visible afterglow under ambient conditions. In particular, the FXylB-DOBPDA@TPA codoped system achieves TADF-promoted long afterglow with lifetimes exceeding 100 ms. Additionally, reversible mechanochromic luminescence is observed, indicating multistimuli-responsive behavior. The combination of experimental analyses and theoretical calculations reveals that subtle changes in substituents critically influence intramolecular charge transfer and excited-state dynamics. These results offer valuable insights into molecular design strategies for achieving tunable emission in solid-state materials. With their integrated TADF, afterglow, and stimuli-responsive properties, these multifunctional materials demonstrate significant potential for applications in organic light-emitting diodes (OLEDs), mechanical sensors, anticounterfeiting labels, and optical storage technologies.
AB - A series of spirofluorene–triarylborane derivatives bearing tunable triarylamine donors (–H, –OMe, –SMe) were designed and synthesized to systematically investigate substituent effects on their photophysical behaviors. The methoxy-substituted compound FXylB-DOBPDA exhibits efficient thermally activated delayed fluorescence (TADF), characterized by a small singlet–triplet energy gap (ΔEST) of 0.05 eV, along with notable aggregation-induced emission enhancement (AIEE). Remarkably, through a host–guest doping strategy using triphenylamine (TPA) as the matrix, the system displays clearly visible afterglow under ambient conditions. In particular, the FXylB-DOBPDA@TPA codoped system achieves TADF-promoted long afterglow with lifetimes exceeding 100 ms. Additionally, reversible mechanochromic luminescence is observed, indicating multistimuli-responsive behavior. The combination of experimental analyses and theoretical calculations reveals that subtle changes in substituents critically influence intramolecular charge transfer and excited-state dynamics. These results offer valuable insights into molecular design strategies for achieving tunable emission in solid-state materials. With their integrated TADF, afterglow, and stimuli-responsive properties, these multifunctional materials demonstrate significant potential for applications in organic light-emitting diodes (OLEDs), mechanical sensors, anticounterfeiting labels, and optical storage technologies.
KW - aggregation-induced emission enhancement (AIEE)
KW - long afterglow
KW - mechanochromism
KW - spirofluorene–triarylborane
KW - thermally activated delayed fluorescence (TADF)
UR - https://www.scopus.com/pages/publications/105027595310
U2 - 10.1021/acsami.5c21611
DO - 10.1021/acsami.5c21611
M3 - Article
C2 - 41424114
AN - SCOPUS:105027595310
SN - 1944-8244
VL - 18
SP - 2277
EP - 2288
JO - ACS Applied Materials and Interfaces
JF - ACS Applied Materials and Interfaces
IS - 1
ER -