四川大学游劲松团队揭示了窄带荧光发射体设计中的中心对称效应——从单到双二氟硼芯。相关研究成果发表在2024年12月25日出版的国际学术期刊《美国化学会杂志》。

由于制造超高清有机发光二极管显示器（UHD-OLED）的巨大潜力，窄带荧光发射器正受到广泛关注。推出创新机制来设计新的高性能窄带荧光发射器，是学术界和工业界的共同愿望。理论计算表明，与之前报道的具有单氟硼核的不对称结构相比，中心对称的二苯胺联吡啶二氟化硼框架（cs-DAPBF2）的结构弛豫显著降低，为窄带荧光发射体的发展创造了新的机会。

该文中，研究人员提出了一种双螯合辅助的C-H/C-H同源偶联策略，可以有效地合成3,3′-氨基-2,2′-联吡啶骨架，从而能够直接构建一系列对称的基于cs-DAPBF2的荧光发射体。

通过分子优化，研究人员开发了一种高性能的窄带绿色荧光发射体cs-DMeAPBF2-MP，其半峰全宽（fwhm）为20 nm，光致发光量子产率（ΦPL）为98%，摩尔吸光系数（ε）为2.10×10⁴ M^–1 cm^–1，水平偶极比（Θ//）为77%。这些特性使cs-DMeAPBF2-MP成为，制造高效窄带绿色有机发光二极管（OLEDs）的有前景的候选者，其效率衰减最小。

该项研究代表了DAPBF2架构，在高性能OLEDs窄带荧光发射器设计中的首次成功应用。

附：英文原文

Title: Unveiling the Centrosymmetric Effect in the Design of Narrowband Fluorescent Emitters: From Single to Double Difluoroboron Cores

Author: Ge Yang, Junjie Liu, Yudong Yang, Zhengyang Bin, Jingsong You

Issue&Volume: December 25, 2024

Abstract: Narrowband fluorescent emitters are receiving significant attention due to the great potential for creating ultrahigh-definition organic light-emitting diode displays (UHD-OLED). Unveiling innovative mechanisms to design new high-performance narrowband fluorescent emitters is a concerted endeavor in both academic and industrial circles. Theoretical calculations reveal that the centrosymmetric dianilido-bipyridine boron difluoride framework (cs-DAPBF2) exhibits significantly reduced structural relaxation compared to previously reported asymmetric structures with monofluoroboron cores, creating new opportunities for the development of narrowband fluorescent emitters. In this work, we present a dual chelation-assisted C–H/C–H homocoupling strategy to efficiently synthesize the 3,3′-amino-2,2′-bipyridine skeleton, enabling the straightforward construction of a series of symmetric cs-DAPBF2-based fluorescent emitters. Through molecular optimization, we have developed a high-performance narrowband green fluorescent emitter, cs-DMeAPBF2-MP, which demonstrates a narrow full width at half-maximum (fwhm) of 20 nm, a high photoluminescence quantum yield (ΦPL) of 98%, a large molar absorptivity (ε) of 2.10 × 104 M–1 cm–1, and a high horizontal dipole ratio (Θ//) of 77%. These properties make cs-DMeAPBF2-MP a promising candidate for fabricating high-efficiency, narrowband green organic light-emitting diodes (OLEDs) with minimal efficiency roll-off. This study represents the first successful application of the DAPBF2 architecture in the design of narrowband fluorescent emitters for high-performance OLEDs.

DOI: 10.1021/jacs.4c15233

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c15233