LAUSR

Abstract For developing novel photothermal converting agent with temperature self-reading-out function in photothermal therapy, NaYF4:Dy3+/Yb3+@NaYF4:Er3+/Yb3+ core-shell nanostructure was designed and prepared via a thermal decomposition technique. The temperature sensing, fluorescence temperature quenching and photothermal conversion properties were investigated. The measurement of fluorescence intensity ratios (FIRs) indicated that the NaYF4:Er3+/Yb3+ shell has a good performance in temperature sensing. Meanwhile, it was also confirmed that the temperature quenching of Er3+ green fluorescence was mainly induced by the increasing nonradiative transition probability of 4S3/2 state with elevating sample temperature. Furthermore, the photothermal conversion was studied based on the experimentally confirmed temperature sensing of the shell structure. It was proved that the core-shell nanoparticles can effectively convert the excitation luminous energy into heat energy. All the results indicated that the designed nanoparticles might be an excellent photothermal converter with optical temperature sensing for promising application in photothermal therapy.