CsPbBr3钙钛矿/Pt杂化纳米结构中等离激元-激子耦合引起的发光猝灭和辐射速率减小

摘要

研究了半导体纳米粒子(SNPs)-金属纳米颗粒(MNPs)耦合导致的SNPs的发光强度猝灭和荧光寿命增强潜在的物理机制,并用传统F?ster共振能量传递(FRET)理论描述和分析实验结果.光致发光光谱(PL)和时间分辨光谱观测表明,SNPs的PL强度发生了明显的猝灭,荧光寿命从17.7 ns到30.8 ns延长了近2倍.这种杂化纳米结构表现出不同于杂化前各独立组分的新的协同相互作用光学性质.胶体化学使杂化SNPS-MNP纳米结构中SNPS和MNP构成一个新的单元称为等离激子激元(Plexciton)或激子等离子激元(Exci-mon),这已在一系列杂化结构中被确认.基于泵浦-探测技术的飞秒瞬态吸收(TA)的实验结果证实了这种从激子-等离激元到等离激子的转换.实验结果分析表明,传统F?ster共振能量传递理论不能很好地描述实验结果,在金属存在的情况下,还需要对该理论进一步调整和改进.%The mechanism of photoluminescence ( PL) quenched and lifetime enhanced by semicon-ductor nanoparticles ( SNPs )-metal nanoparticles ( MNPs ) couple were investigated and the experi-mental results have been described and analyzed by the conventional F?ster resonance energy transfer ( FRET) . The plasmonically coupled SNPs have demonstrated the PL quenched obviously and lifetime enhanced from 17. 7 ns to 30. 8 ns, near to 2 times. The hybrid colloidal CsPbBr3 perovskite SNPs/Pt MNPs ( S-M) structures exhibit novel optical properties due to the synergetic interaction between the individual components. In hybrid S-M nanostructures, colloidal chemistry incorporates SNP and MNP into a single unit resulting in the formation of plexciton ( or excimon) which has now been established in a series of hybrid structures. The experimental results of femtosecond transient absorption ( TA) spectroscopy based on the time-resolved pump-probe confirm the transformation from excitons to plex-citons. It was found that the experimental data can't be well described by the theory based on conven-tional FRET. To modify and improve the conventional FRET is needed.