The invention relates to
rare earth upconversion materials and preparation methods thereof, in particular to a dye-sensitized
rare earth upconversion material and a preparation method thereof and aims to solve the technical problem of low light emitting efficiency of existing dye-sensitized upconversion materials. The dye-sensitized
rare earth upconversion material is in a five-layer hollow spherical shell structure which is composed of an inner layer, an inner transmitting layer, a light emitting layer, an outer transmitting layer and an outer layer sequentially from inside to outside, and
infrared dye molecules are connected to surfaces of the inner layer and the outer layer of the hollow spherical shell structure. The preparation method includes: taking a
silicon dioxide nanosphere as a template,
coating the spherical surface of the template with an upconversion shell layer as the light emitting layer,
etching the
silicon dioxide to obtain a hollow upconversion spherical shell namely the light emitting layer, and simultaneously
coating inner and outer surfaces of the hollow spherical shell with Yb<3+>-containing transmitting shell
layers and Nd<3+>-containing surface shell
layers to construct efficient bidirectional energy transmitting passages, and finally simultaneously connecting the dye molecules to the inner and outer surfaces of the spherical shell to serve as
energy absorption antennas. The dye-sensitized rare earth upconversion material is applicable to the biological field of
drug loading and
controlled release.