Materials Chemistry

Bright Room-Temperature Phosphorescence from Mixed Mothballs Enabling Specific Identification of the Illegal Component

Authors

  • Xuepeng Zhang The Hong Kong University of Science and Technology & University of Science and Technology of China ,
  • Junkai Liu The Hong Kong University of Science and Technology ,
  • Biao Chen University of Science and Technology of China ,
  • Xuewen He The Hong Kong University of Science and Technology ,
  • Xueyu Li Hokkaido University ,
  • Peifa Wei The Hong Kong University of Science and Technology ,
  • Peng Fei Gao The Hong Kong University of Science and Technology ,
  • Guoqing Zhang University of Science and Technology of China ,
  • Jacky W. Y. Lam The Hong Kong University of Science and Technology ,
  • Ben Zhong Tang The Chinese University of Hong Kong, Shenzhen

Abstract

Ultralong organic room-temperature phosphorescence (RTP) with high brightness was rarely achieved to date despite their huge potential in various applications such as lighting, sensing, anti-counterfeiting and imaging. Herein, by exploiting π-π* nature of the lowest excited triplet state of naphthalene (NL, the traditional active ingredient for mothball) and intersystem crossingpromoting factors from 1,4-dichlorobenzene (DCB, a safer alternative to NL as mothball), we report a simple and novel guest/host system, namely NL/DCB, that could produce strong green RTP with quantum yield > 20% and lifetime > 0.76 s (afterglow duration > 10 s) at ambient conditions. The RTP performance with simultaneous high efficiency and ultralong lifetime is superior to that of most purely organic (metal-free) RTP materials reported so far. Control experiments with different hosts and first-principle theoretical calculations revealed that the robust RTP behavior in the unique NL/DCB system was mainly attributed to a combination of clusterexciton formation and external heavy atom effect. Meanwhile, the remarkable “turn-on” type RTP to naked eyes allows fast and specific detection of illegal NL mothball using DCB as a sensor, which is valuable in household as well as industrial applications.

Content

Thumbnail image of Manuscript PDF.pdf

Supplementary material

Thumbnail image of Supporting Information.pdf
Supporting Information for "Bright Room-Temperature Phosphorescence from Mixed Mothballs Enabling Specific Identification of the Illegal Component"
Materials, methods, supplementary photophysical properties at RT and 77 K and DFT data, including Figures S1-S12.