Lanthanide nanoparticles ignite dark molecular triplets

• 作者: Jin Xu Xueyuan Chen
• 来源期刊: 中国科学：化学（英文版）
• 年，卷（期）: 2021,（4）
• 所属期刊栏目: HIGHLIGHTS
• 页码范围: 511-512
• 页数: 2页
• 语种: 英文

摘要

Molecular triplets have attracted great interest across multidisciplinary fields of the research ranging from thermally activated delayed fluorescence [1], triplet-triplet annihilation (TTA) upconversion [2], to photodynamic therapy relying on TTA between triplet photosensitizers and surrounding triplet oxygen to generate singlet oxygen species [3].Molecular triplets are normally'dark states' because of the spin-forbidden nature of direct optical transition from a singlet ground state (S0) to a triplet excited state (T1).To circumvent this limitation, triplet dynamics are conventionally controlled via the heavy atom effect to enhance intersystem crossing from the singlet to the triplet excited state (Sn→Tn) [4], or via highest occupied molecular orbital-lowest unoccupied molecular orbital engineering to tune the gap between excited singlet and triplet states.However, it remains challenging to break the spin-forbidden rule for accomplishing the direct optical transition from S0 to T1.