Precisely tailored shell thickness and Ln³⁺content to produce multicolor emission from Nd³⁺-sensitized Gd³⁺-based core/shell/shell UCNPs through bi-directional energy transfer

Abstract

Precise tailoring of the shell thickness and Ln3+ content produced multicolour emissions from core/shell/shell UCNPs via a bi-directional energy transfer mechanism.

Recent Advances in 2D Rare Earth Materials

“…[79] RE-doped UCNPs are attractive materials for their ability to convert NIR light into VIR emission by the photon UC process. [144][145][146] Typically, these UCNPs are formed by activators like Er 3+ /Ho 3+ and sensitizers like Yb 3+ /Nd 3+ . [54] After continuing absorption of NIR photons of sensitizers, energy transfer from sensitizers induces the electrons of the activators to a higher excited state which can produce photons from UV to NIR band.…”

Terras Raras: Tabela Periódica, Descobrimento, Exploração No Brasil E Aplicações

“…[78][79][80] Em particular, suas propriedades luminescentes, conferidas pelas intensas e estreitas bandas de emissão, resultantes de transições do tipo f-f, geram cores específicas em dispositivos luminescentes. 81,82 Assim, materiais luminescentes contendo terras raras possuem extensa aplicação em dispositivos de iluminação, como displays emissores e lâmpadas fluorescentes, 83,84 sendo extensamente processados na forma de luminóforos de estado sólido, [85][86][87][88][89][90][91][92][93][94][95][96][97][98][99] materiais híbridos e compostos de coordenação, [100][101][102][103][104][105][106][107][108] vidros, [109][110][111][112][113][114] híbridos magnéticos-luminescentes, 115,116 entre muitos outros. Além disso, a utilização de ferramentas teóricas para a descrição da luminescência de lantanídeos é extremamente útil para o aprimoramento e adaptação das propriedades observadas.…”

A UV-visible-NIR active smart photocatalytic system based on NaYbF4:Tm3+ upconverting particles and Ag3PO4/H2O2 for photocatalytic processes under light on/light off conditions

“…The UCPs can successively absorb two or more photons of relatively low energy photons (NIR photons) via intermediate long-lived energy states and then emit higher energy photons (in the UV-Vis region) upon relaxation through a non-linear optical process known as upconversion [41][42][43][44][45] . During this anti-Stokes 8Q emission < Q excitation ) process, the UCPs are excited to a higher energy level through the population of intermediate energy levels and subsequently emit a higher energy photon [44][45][46][47][48][49][50][51][52] . The photons emitted by the UCPs in the UV-Vis region can be exploited to photo-excite any photocatalysts with adequate band gap (E g ) that matches the energy of the emitted photon (E g = hv).…”