Mei Sheng, Zhou Jiajia, Sun Hong-Tao, Cai Yangjian, Sun Ling-Dong, Jin Dayong, Yan Chun-Hua
Institute for Biomedical Materials & Devices (IBMD) Faculty of Science University of Technology Sydney New South Wales 2007 Australia.
Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications PKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistry College of Chemistry and Molecular Engineering Peking University Beijing 100871 China.
Adv Sci (Weinh). 2021 Jan 29;8(6):2003325. doi: 10.1002/advs.202003325. eCollection 2021 Mar.
At the organic-inorganic interface of nanocrystals, electron-phonon coupling plays an important but intricate role in determining the diverse properties of nanomaterials. Here, it is reported that highly doping of Yb ions within the nanocrystal host can form an energy-migration network. The networking state Yb shows both distinct Stark splitting peak ratios and lifetime dynamics, which allows quantitative investigations of quenching and thermal activation of luminescence, as the high-dimensional spectroscopy signatures can be correlated to the attaching and de-attaching status of surface molecules. By in-situ surface characterizations, it is proved that the Yb-O coordination associated with coordinated water molecules has significantly contributed to this reversible effect. Moreover, using this approach, the prime quencher -OH can be switched to -CH in the wet-chemistry annealing process, resulting in the electron-phonon coupling probability change. This study provides the molecular level insights and dynamics of the surface dark layer of luminescent nanocrystals.
在纳米晶体的有机-无机界面处，电子-声子耦合在决定纳米材料的多样性质方面起着重要但复杂的作用。在此，有报道称在纳米晶体基质中高度掺杂镱离子可形成能量迁移网络。处于网络状态的镱表现出独特的斯塔克分裂峰比率和寿命动力学，这使得能够对发光的猝灭和热激活进行定量研究，因为高维光谱特征可与表面分子的附着和脱附状态相关联。通过原位表面表征，证明与配位水分子相关的Yb-O配位对这种可逆效应有显著贡献。此外，使用这种方法，在湿化学退火过程中，主要猝灭剂-OH可转变为-CH，导致电子-声子耦合概率发生变化。这项研究提供了发光纳米晶体表面暗层的分子水平见解和动力学。
