橡胶
化学
光子上转换
超快激光光谱学
激发态
光化学
单重态裂变
三重态
自由基离子
离子
猝灭(荧光)
单重态
量子产额
原子物理学
荧光
光谱学
分子
有机化学
物理
量子力学
作者
Jeffrey T. DuBose,Gábor Szabó,Jishnudas Chakkamalayath,Prashant V. Kamat
标识
DOI:10.1021/acs.jpca.2c04499
摘要
The ability to manipulate low-energy triplet excited states into higher-energy emissive singlet states, a process known as photon upconversion (UC), has potential applications in bioimaging, photocatalysis, and in increasing the efficiency of solar cells. However, the overall UC mechanism is complex and can involve many intermediate states, especially when semiconductors such as lead halide perovskites are used to sensitize the required triplet states. Using a combination of pulse radiolytic and electrochemical techniques, we have now explored the transient features of rubrene─a commonly employed triplet annihilator in UC systems. The rubrene triplet, radical anion, and radical cation species yield unique spectra that can serve as spectral fingerprints to distinguish between transient species formed during UC processes. Using detailed kinetic studies, we have succeeded in establishing that the rubrene triplets are susceptible to self-quenching (kquench = 3.6 × 108 M-1 s-1), and as the triplets decay, an additional transient feature is observed in the transient absorption spectra. This new feature indicates a net electron transfer process occurs to form the radical cation and anion as the triplets recombine. Taken together, this work provides a comprehensive picture of the excited state and transient features of rubrene and will be crucial for understanding the mechanism(s) of photon upconversion systems.
科研通智能强力驱动
Strongly Powered by AbleSci AI