Ultrafast Relaxation Dynamics of Luminescent Rod-Shaped, SilverDoped AgxAu25-x Clusters

	Ultrafast Relaxation Dynamics of Luminescent Rod-Shaped, SilverDoped AgxAu25-x Clusters
	Zhou, Meng 1; Zhong, Juan 2; Wang, Shuxin 3,4; Guo, Qianjin 1; Zhu, Manzhou 3,4; Pei, Yong 2; Xia, Andong 1
刊名	JOURNAL OF PHYSICAL CHEMISTRY C
	2015-08-13
卷号	119 期号:32 页码:18790-18797
英文摘要	The luminescent ligand protected metal clusters have attracted considerable attentions while the origin of the emission still remains elusive. As recently reported in our previous work, the rod-shaped Au-25 cluster possesses a low photoluminescence quantum yield (QY = 0.1%), whereas substituting silver atoms for central gold atom in the rod-shaped Au-25 cluster can drastically enhance the photoluminescence with high quantum yield (QY = 40.1%). To explore the enhancement mechanism of fluorescence, femtosecond transient absorption spectroscopy is performed to determine the electronic structure and ultrafast relaxation dynamics of the highly luminescent silver-doped AgxAu25 cluster by comparing the excited state dynamics of doped and undoped Au-25 rod cluster, it is found that the excited state relaxation in AgxAuls, is proceeded with an ultrafast ps) internal conversion and a subsequent nuclear relaxation (-20.7 ps), followed by slow (7.4 ms) decay back to the ground state. Meanwhile, the observed nuclear relaxation is much faster in AgxAu25. ('-.'20.7 ps) compared to that in undoped Au-25 rod (,52 ps). We conclude that it is the central Ag atom that stabilizes the charges on LUMO orbital and enhances the rigidity of Agx.Au-25, cluster that leads to strong fluorescence. Meanwhile, coherent oscillations around similar to 08 THz were observed in both clusters, indicating the symmetry preservation from Au cluster to Ag alloying Au clusters. The present results provide new insights for the structure-related excited state behaviors of luminescent ligand protected Ag alloying Au clusters.
收录类别	SCI
语种	英语
公开日期	2016-05-09
内容类型	期刊论文
源URL	[http://ir.iccas.ac.cn/handle/121111/27740]
专题	化学研究所_光化学实验室
作者单位	1.Chinese Acad Sci, Inst Chem, Key Lab Photochem, BNLMS, Beijing 100190, Peoples R China 2.Xiangtan Univ, Minist Educ, Key Lab Environm Friendly Chem & Applicat, Dept Chem, Xiangtan 411105, Hunan, Peoples R China 3.Anhui Univ, Dept Chem, Hefei 230601, Anhui, Peoples R China 4.Anhui Univ, Ctr Atom Engn Adv Mat, Hefei 230601, Anhui, Peoples R China
推荐引用方式 GB/T 7714	Zhou, Meng,Zhong, Juan,Wang, Shuxin,et al. Ultrafast Relaxation Dynamics of Luminescent Rod-Shaped, SilverDoped AgxAu25-x Clusters[J]. JOURNAL OF PHYSICAL CHEMISTRY C,2015,119(32):18790-18797.
APA	Zhou, Meng.,Zhong, Juan.,Wang, Shuxin.,Guo, Qianjin.,Zhu, Manzhou.,...&Xia, Andong.(2015).Ultrafast Relaxation Dynamics of Luminescent Rod-Shaped, SilverDoped AgxAu25-x Clusters.JOURNAL OF PHYSICAL CHEMISTRY C,119(32),18790-18797.
MLA	Zhou, Meng,et al."Ultrafast Relaxation Dynamics of Luminescent Rod-Shaped, SilverDoped AgxAu25-x Clusters".JOURNAL OF PHYSICAL CHEMISTRY C 119.32(2015):18790-18797.