Reversible On-Off Switching of Excitation-Wavelength-Dependent Emission of a Phosphorescent Soft Salt Based on Platinum(II) Complexes

Jiangang Li, Kexin Chen, Juan Wei, Yun Ma, Ruyi Zhou, Shujuan Liu, Qiang Zhao, Wai Yeung Wong

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)


Excitation-wavelength-dependent (Ex-De) emission materials show excellent potential in diverse advanced photonic areas. Of significant importance is the on-demand regulation of the Ex-De luminescence behavior of these materials, which is previously unprecedented. In this study, we report on a platinum(II) complex-based phosphorescent soft salt S1 ([Pt(tpp)(ed)]+[Pt(ftpp)(CN)2]- (where ttp = 2-(4-(trifluoromethyl)phenyl)pyridine, ed = ethane-1,2-diamine, and ftpp = 2-(4-fluoro-3-(trifluoromethyl)phenyl)pyridine)) with Ex-De photoluminescence (PL) property. UV-visible absorption and PL spectra of S1 were recorded in DMSO-H2O mixture (1 × 10-3 M) with various H2O fractions to investigate its ground and excited states. Interestingly, the PL spectra of S1 powder show that its maximum emission peak is red-shifted from 595 to 644 nm upon excitation at different wavelengths from 360 to 520 nm, accompanied by an obvious emission color change from yellow-orange to red. Furthermore, confocal laser scanning fluorescence microscopy was employed to determine the PL property of self-assembled uniform S1 nanostructure, and the result shows that the Ex-De emission behavior is absent. On the basis of these results, we conclude the various Pt(II)···Pt(II) distances that exist are the major factor responsible for the properties of the Ex-De PL of S1 powder. Thus, for the first time, reversible on-off switching of Ex-De PL of S1 was achieved by manipulating its Pt(II)···Pt(II) distances through mechanical stress and vapor fuming. Finally, we demonstrate the high-level anticounterfeiting applications via on-demand multicolor displays.

Original languageEnglish
Pages (from-to)18317-18324
Number of pages8
JournalJournal of the American Chemical Society
Issue number43
Publication statusPublished - 3 Nov 2021

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

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