【摘 要】
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Photon upconversion of lanthanides has been a powerful means to convert low-energy photons into high-energy ones.However,in contrast to the mostly investigated lanthanide ions,it has remained a challenge for the efficient upconversion of Nd3+due to the de
【机 构】
：
State Key Laboratory of Luminescent Materials and Devices,Guangdong Provincial Key Laboratory of Fib
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Photon upconversion of lanthanides has been a powerful means to convert low-energy photons into high-energy ones.However,in contrast to the mostly investigated lanthanide ions,it has remained a challenge for the efficient upconversion of Nd3+due to the deleterious concentration quenching effect.Here we report an efficient strategy to enhance the upconversion of Nd3+through the Yb3+-mediated energy cycling in a core-shell-shell nanostructure.Both Nd3+and Yb3+are confined in the interlayer,and the presence of Yb3+in the Nd-sublattice provides a more matched energy for the upconversion tran-sitions occurring at the intermediate state of Nd3+towards much better population at its emissive levels.Moreover,this design also minimizes the possible cross-relaxation processes at both intermediate level and the emissive levels of Nd3+which are the primary factors limiting the upconversion performance for the Nd3+-doped materials.Such energy cycling-enhanced upconversion shows promise in temperature sensing.
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