School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
Shandong Provincial Engineering and Technical Center of Light Manipulations, Shandong Provincial Key Laboratory of Optics and Photonic Device, School of Physics and Electronics, Shandong Normal University, Jinan 250100, China.
Anal Chem. 2022 Mar 1;94(8):3718-3726. doi: 10.1021/acs.analchem.1c05597. Epub 2022 Feb 15.
Singlet oxygen (O) is an important reactive oxygen species (ROS) that is intensively involved in natural photochemical and photobiological processes. Herein, selectively lighting up O is achieved in the aggregation-induced emission (AIE) of electrochemiluminescence (ECL) from the Zn-mediated AIE assembly of Au nanoclusters (Zn-AIE-AuNCs). Zn-AIE-AuNCs can exhibit efficient AIE ECL and photoluminescence (PL) along with O generation in energy and charge transfer routes, respectively. The AIE ECL of the Zn-AIE-AuNCs/tripropylamine (TEA) system in carbonate buffer is located around 703 nm with the dimeric aggregate of O as an emitter because electrochemically oxidizing coexisted Zn-AIE-AuNCs and TEA in carbonate buffer would promote the oxygen vacancy (O) of Zn-AIE-AuNCs, which could selectively enable the generation of emissive singlet oxygen in the energy transfer route by effectively transferring the energy from excited singlet Zn-AIE-AuNCs to the triplet ground state of dissolved oxygen (O). No emissive O is detected via electrochemically oxidizing the Zn-AIE-AuNCs in the case without either carbonate buffer or TEA, and the Zn-AIE-AuNCs/TEA system can only exhibit AIE ECL around 485 nm with Zn-AIE-AuNCs as the emitter in carbonate-free buffers. Photoexciting Zn-AIE-AuNCs merely brings out band-gap-engineered AIE PL around ∼485 nm with Zn-AIE-AuNCs as the emitter, which manifests that the O generated in the charge transfer route via photoexciting Zn-AIE-AuNCs is un-emissive. This work not only proposes an effective strategy for AIE with O as an emitter but also opens a promising way to selectively light up O.
单线态氧（O）是一种重要的活性氧物种（ROS），它广泛参与自然光化学和光生物学过程。在此，通过锌介导的金纳米团簇（Zn-AIE-AuNCs）的聚集诱导发光（AIE）的电化学发光（ECL）实现了对 O 的选择性点亮。Zn-AIE-AuNCs 可以在能量和电荷转移途径中分别表现出高效的 AIE ECL 和光致发光（PL）以及 O 的产生。在碳酸盐缓冲液中，Zn-AIE-AuNCs/三丙胺（TEA）体系的 AIE ECL 位于 703nm 左右，因为电化学氧化共存的 Zn-AIE-AuNCs 和 TEA 在碳酸盐缓冲液中会促进 Zn-AIE-AuNCs 的氧空位（O），这可以通过有效地将激发态 Zn-AIE-AuNCs 的能量转移到溶解氧（O）的三重基态，从而选择性地在能量转移途径中产生发射单线态氧。如果没有碳酸盐缓冲液或 TEA，通过电化学氧化 Zn-AIE-AuNCs 不会检测到发射单线态氧，并且 Zn-AIE-AuNCs/TEA 体系只能在无碳酸盐缓冲液中以 Zn-AIE-AuNCs 为发射体在 485nm 左右发出 AIE ECL。光激发 Zn-AIE-AuNCs 只能发出带隙工程化的 AIE PL，其发射体约为 485nm，这表明通过光激发 Zn-AIE-AuNCs 在电荷转移途径中产生的 O 是不发射的。这项工作不仅提出了一种以 O 为发射体的 AIE 的有效策略，而且为选择性点亮 O 开辟了一条有前途的途径。
