21:I[432972,["/_next/static/chunks/bb923814e1f4d2e9.js","/_next/static/chunks/dd3ee9f5b7716ca6.js","/_next/static/chunks/4204a0ae82542ca8.js","/_next/static/chunks/1270dead247da766.js","/_next/static/chunks/6e1aa89a642f40be.js","/_next/static/chunks/2d7aa753e81324a8.js","/_next/static/chunks/8ffd0b71567920d8.js","/_next/static/chunks/67ea6dfd21f16c5f.js","/_next/static/chunks/24eb4379f68013fd.js","/_next/static/chunks/b8cd775ffdf935bd.js","/_next/static/chunks/983103cd9eb7b428.js","/_next/static/chunks/263f2cdcb9aa2341.js","/_next/static/chunks/294b9525248c8e5f.js"],"default"] 22:T426,Among the various upconversion (UC) materials, sodium yttrium fluoride doped with ytterbium and erbium (NaYF₄:Yb³⁺,Er³⁺) is the most widely studied owing to its high UC efficiency. Nonetheless, UC mechanisms are not yet fully understood and, in particular, near-infrared-to-red UC mechanisms are still under debate. Herein, we examine UC mechanisms in Er³⁺-based UC materials. Most importantly, the ⁴F_3/2 and ⁴F_5/2 states of Er³⁺ were found to be important intermediate states for strong red emission, for the first time. The cross relaxation between the Er³⁺ ions, back energy transfer from Er³⁺ to Yb³⁺, and relative doping concentrations of Er³⁺ and Yb³⁺ in NaYF₄:Yb³⁺,Er³⁺ were found to play important roles in the relative intensity between red and green emissions. The proposed UC mechanism will provide design principles for various Er³⁺-based UC materials.

#	Concept	H-Index	Publications	Citations
1	Engineering	2	2	54
2	Medicine	1	1	21
3	Biomedical Engineering	1	1	21
4	Chemical Engineering	1	1	33
5	Immunology	1	1	21

	Year	Citations

About

Top Concepts