Ou Weihui, Zou Yu, Wang Kewei, Gong Wenbin, Pei Renjun, Chen Liwei, Pan Zhenghui, Fu Dongdong, Huang Xin, Zhao Yanfei, Lu Weibang, Jiang Jiang
i-Lab and Division of Nanobiomedicine, CAS Key Laboratory of Nano-Bio Interface, CAS Center for Excellence in Nanoscience, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences , Suzhou 215123, China.
University of Chinese Academy of Sciences , Beijing 100049, China.
J Phys Chem Lett. 2018 Jan 18;9(2):274-280. doi: 10.1021/acs.jpclett.7b03305. Epub 2018 Jan 2.
Active control of nanocrystal optical and electrical properties is crucial for many of their applications. By electrochemical (de)lithiation of CuSe, a highly doped semiconductor, dynamic and reversible manipulation of its NIR plasmonics has been achieved. Spectroelectrochemistry results show that NIR plasmon red-shifted and reduced in intensity during lithiation, which can be reversed with perfect on-off switching over 100 cycles. Electrochemical impedance spectroscopy reveals that a Faradaic redox process during CuSe (de)lithiation is responsible for the optical modulation, rather than simple capacitive charging. XPS analysis identifies a reversible change in the redox state of selenide anion but not copper cation, consistent with DFT calculations. Our findings open up new possibilities for dynamical manipulation of vacancy-induced surface plasmon resonances and have important implications for their use in NIR optical switching and functional circuits.
对纳米晶体光学和电学性质进行主动控制对其许多应用至关重要。通过对高掺杂半导体CuSe进行电化学（脱）锂处理，实现了对其近红外等离子体激元的动态可逆操纵。光谱电化学结果表明，在锂化过程中，近红外等离子体激元发生红移且强度降低，在100个循环中可实现完美的开-关切换，且这种变化是可逆的。电化学阻抗谱表明，CuSe（脱）锂过程中的法拉第氧化还原过程是光学调制的原因，而非简单的电容充电。X射线光电子能谱分析确定了硒化物阴离子而非铜阳离子的氧化还原状态发生了可逆变化，这与密度泛函理论计算结果一致。我们的研究结果为动态操纵空位诱导的表面等离子体共振开辟了新的可能性，并对其在近红外光开关和功能电路中的应用具有重要意义。
