Luminescent rare earth complexes based on interconfigurational 5d-4f transition have characteristics of adjustable emission spectra and short excited state lifetimes,showing potential applications in display,lighting ...Luminescent rare earth complexes based on interconfigurational 5d-4f transition have characteristics of adjustable emission spectra and short excited state lifetimes,showing potential applications in display,lighting and other fields.In this work,nine Ce^(3+),Eu^(2+)and Yb^(2+)complexes with spiro-bis(pyrazolyl)borate ligands,where pyrazolyl stands for pyrazolyl,3-methylpyrazolyl,or 3,5-dimethylpyrazolyl,were designed and synthesized.Ce^(3+)complexes show emission colors of blue,with photoluminescence quantum yields(PLQYs)of 94%-100%;Eu^(2+)complexes show emission colors of yellow-green,with PLQYs of 60%-78%;Yb^(2+)complexes show emission colors of orange or red,with PLQYs of 3%-4%.In addition,the crystal structures and theoretical calculation results show C-H…M interactions between bridge-head H atoms of the spirane and central metal ions in these complexes.It is found that the introduction of spirane with large steric hindrance and the existence of C-H…M interactions can improve the stability of the complexes in air atmosphere.展开更多
基金Project supported by the National Key R&D Program of China(2021YFB3500400,2021YFB3501800,2022YFB3503700,2023YFB3506901)the National Natural Science Foundation of China(22071003,92156016,62104013)。
文摘Luminescent rare earth complexes based on interconfigurational 5d-4f transition have characteristics of adjustable emission spectra and short excited state lifetimes,showing potential applications in display,lighting and other fields.In this work,nine Ce^(3+),Eu^(2+)and Yb^(2+)complexes with spiro-bis(pyrazolyl)borate ligands,where pyrazolyl stands for pyrazolyl,3-methylpyrazolyl,or 3,5-dimethylpyrazolyl,were designed and synthesized.Ce^(3+)complexes show emission colors of blue,with photoluminescence quantum yields(PLQYs)of 94%-100%;Eu^(2+)complexes show emission colors of yellow-green,with PLQYs of 60%-78%;Yb^(2+)complexes show emission colors of orange or red,with PLQYs of 3%-4%.In addition,the crystal structures and theoretical calculation results show C-H…M interactions between bridge-head H atoms of the spirane and central metal ions in these complexes.It is found that the introduction of spirane with large steric hindrance and the existence of C-H…M interactions can improve the stability of the complexes in air atmosphere.
