Justice Babu Kaliyamoorthy, Chazhoor Asokan Anil, Shukla Ayushi, Kaur Arshdeep, Sachdeva Manvi, Ghosh Hirendra N
Institute of Nano Science and Technology, Mohali, Punjab 140306, India.
School of Chemical Science, National Institute of Science Education and Research, Jatni, Bhubaneswar, Odisha 752050, India.
J Phys Chem Lett. 2024 Sep 26;15(38):9677-9685. doi: 10.1021/acs.jpclett.4c01853. Epub 2024 Sep 16.
Colloidal one-dimensional (1D) perovskite nanorods (NRs) and metal epitaxial heterostructures (HSs) are the promising class of new materials for efficient photovoltaic and photocatalytic applications. Besides, fundamental photophysical properties and its device applications of 1D perovskite-metal HSs are limited due to their challenging synthetic protocols and difficulties in forming epitaxial growth between covalent and ionic bonds. Herein, we have synthesized the CsPbBr perovskite NRs-platinum (Pt) nanoparticles (NPs) (CsPbBr/Pt) epitaxial HS using cation exchange followed by chemical reduction methods with the orthorhombic CsCuBr NRs. Here, the tertiary ammonium ions extensively helped to form the 1D CsCuBr, CsPbBr NRs, and CsPbBr/Pt HSs. For CsPbBr/Pt HSs an epitaxial relationship has been established in the (020) plane of orthorhombic CsPbBr with the (020) plane of cubic Pt. Further, femtosecond transient absorption (TA) spectroscopy was employed to study the charge carrier dynamics of CsPbBr/Pt HS. Upon 420 nm photoexcitation, excitons in the conduction band of CsPbBr NRs dissociate by electron transfer (with an ultrafast time of 1.1 ps) to the Pt domain. In addition, charge transfer (CT) was also demonstrated in the CsPbBr/Pt HS, which is ascribed to strong electron coupling and epitaxial growth between CsPbBr and Pt states. This extensive understanding of the electron transfer dynamics of CsPbBr/Pt epitaxial HS may pave the way to designing highly efficient photovoltaic and photocatalytic applications.
胶体一维（1D）钙钛矿纳米棒（NRs）和金属外延异质结构（HSs）是用于高效光伏和光催化应用的一类很有前景的新型材料。此外，由于1D钙钛矿-金属HSs具有挑战性的合成方案以及在共价键和离子键之间形成外延生长的困难，其基本光物理性质及其器件应用受到限制。在此，我们使用阳离子交换，随后采用化学还原方法，以正交晶系的CsCuBr纳米棒合成了CsPbBr钙钛矿纳米棒-铂（Pt）纳米颗粒（NPs）（CsPbBr/Pt）外延异质结构。在此，叔铵离子极大地有助于形成1D CsCuBr、CsPbBr纳米棒和CsPbBr/Pt异质结构。对于CsPbBr/Pt异质结构，已在正交晶系CsPbBr的（020）平面与立方Pt的（020）平面之间建立了外延关系。此外，利用飞秒瞬态吸收（TA）光谱研究了CsPbBr/Pt异质结构的电荷载流子动力学。在420 nm光激发下，CsPbBr纳米棒导带中的激子通过电子转移（超快时间为1.1 ps）解离到Pt域。此外，在CsPbBr/Pt异质结构中也证明了电荷转移（CT），这归因于CsPbBr和Pt态之间的强电子耦合和外延生长。对CsPbBr/Pt外延异质结构电子转移动力学的这种深入理解可能为设计高效的光伏和光催化应用铺平道路。
