Polarized upconversion luminescence(UCL)of lanthanide-doped micro/nano-crystals has shown great promise in single-particle tracking and super-resolution bioimaging.However,because of the spectral line broadening and m...Polarized upconversion luminescence(UCL)of lanthanide-doped micro/nano-crystals has shown great promise in single-particle tracking and super-resolution bioimaging.However,because of the spectral line broadening and multiple sites of lanthanide in upconversion particles(UCPs),the crystal-field(CF)polarization components of UCL are usually undistinguishable.Herein,we report the linearly polarized UCL in LiLuF_(4):Yb^(3+)/Er^(3+) single microcrystals with resolvable CF transition lines and a polarization degree up to 0.82.The CF levels and CF transition lines of Er^(3+),as well as their emission polarization anisotropy,are unraveled for the first time through low-temperature and high-resolution photoluminescence(PL)and UCL spectroscopies.By taking advantage of the well-resolved and highly-polarized CF transition lines of Er^(3+),we demonstrate the application of LiLuF_(4):Yb^(3+)/Er^(3+) single microcrystals as anisotropic UCL probes for orientation tracking.These findings provide fundamental insights into the polarization anisotropy of UCL in lanthanide-doped single particles,thus laying a foundation for the future design of anisotropic luminescent probes towards versatile applications.展开更多
Lanthanide(Ln^(3+))-doped near infrared(NIR)-II luminescent nanoprobes have shown great promise in many technological fields,but are currently limited by the low absorption efficiency of Ln^(3+)due to the forbidden 4f...Lanthanide(Ln^(3+))-doped near infrared(NIR)-II luminescent nanoprobes have shown great promise in many technological fields,but are currently limited by the low absorption efficiency of Ln^(3+)due to the forbidden 4f→4f transition.Herein,we report a novel NIR-II luminescent nanoprobe based on efficient energy transfer from Ce^(3+)to Er^(3+)and Nd^(3+)in sub-10 nm SrS nanocrystals(NCs),which are excitable by using a commercial blue light-emitting diode(LED).Through sensitization by the allowed 4f→5d transition of Ce^(3+),the NCs exhibit strong NIR-II luminescence from Er^(3+)and Nd^(3+)with quantum yields of 2.9%and 2.3%,respectively.Furthermore,by utilizing the intense NIR-II luminescence of Er^(3+)from the thermally coupled Stark sublevels of ^(4)I_(13/2),we demonstrate the application of SrS:Ce^(3+)/Er^(3+)NCs as blue-LED-excitable NIR-II luminescent nanoprobes for ratiometric thermal sensing.These findings reveal the unique advantages of SrS:Ln^(3+)NCs in NIR-II luminescence,which may open up a new avenue for exploring novel and versatile luminescent nanoprobes based on Ln^(3+)-doped sulphide NCs.展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(CAS,XDB20000000)the National Natural Science Foundation of China(U1805252,21875250,11774345,12074379,21771185,12074380,and 21975257)+1 种基金the Youth Innovation Promotion Association of the CAS(2020305)the Natural Science Foundation of Fujian Province(2020I0037).
文摘Polarized upconversion luminescence(UCL)of lanthanide-doped micro/nano-crystals has shown great promise in single-particle tracking and super-resolution bioimaging.However,because of the spectral line broadening and multiple sites of lanthanide in upconversion particles(UCPs),the crystal-field(CF)polarization components of UCL are usually undistinguishable.Herein,we report the linearly polarized UCL in LiLuF_(4):Yb^(3+)/Er^(3+) single microcrystals with resolvable CF transition lines and a polarization degree up to 0.82.The CF levels and CF transition lines of Er^(3+),as well as their emission polarization anisotropy,are unraveled for the first time through low-temperature and high-resolution photoluminescence(PL)and UCL spectroscopies.By taking advantage of the well-resolved and highly-polarized CF transition lines of Er^(3+),we demonstrate the application of LiLuF_(4):Yb^(3+)/Er^(3+) single microcrystals as anisotropic UCL probes for orientation tracking.These findings provide fundamental insights into the polarization anisotropy of UCL in lanthanide-doped single particles,thus laying a foundation for the future design of anisotropic luminescent probes towards versatile applications.
基金supported by the Science and Technology Cooperation Fund between Chinese and Australian Governments(2017YFE0132300)the National Natural Science Foundation of China(22135008,12074379,21875250,12004384)+1 种基金the Natural Science Foundation of Fujian Province(2020I0037,2021L3024)the Chinese Academy of Sciences/State Administration of Foreign Experts Affairs(CAS/SAFEA)International Partnership Program for Creative Research Teams,and Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZR125)。
文摘Lanthanide(Ln^(3+))-doped near infrared(NIR)-II luminescent nanoprobes have shown great promise in many technological fields,but are currently limited by the low absorption efficiency of Ln^(3+)due to the forbidden 4f→4f transition.Herein,we report a novel NIR-II luminescent nanoprobe based on efficient energy transfer from Ce^(3+)to Er^(3+)and Nd^(3+)in sub-10 nm SrS nanocrystals(NCs),which are excitable by using a commercial blue light-emitting diode(LED).Through sensitization by the allowed 4f→5d transition of Ce^(3+),the NCs exhibit strong NIR-II luminescence from Er^(3+)and Nd^(3+)with quantum yields of 2.9%and 2.3%,respectively.Furthermore,by utilizing the intense NIR-II luminescence of Er^(3+)from the thermally coupled Stark sublevels of ^(4)I_(13/2),we demonstrate the application of SrS:Ce^(3+)/Er^(3+)NCs as blue-LED-excitable NIR-II luminescent nanoprobes for ratiometric thermal sensing.These findings reveal the unique advantages of SrS:Ln^(3+)NCs in NIR-II luminescence,which may open up a new avenue for exploring novel and versatile luminescent nanoprobes based on Ln^(3+)-doped sulphide NCs.
