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.
Division of Advanced Materials, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences , Suzhou 215123, China.
ACS Nano. 2017 Apr 25;11(4):3776-3785. doi: 10.1021/acsnano.6b08641. Epub 2017 Apr 13.
Integrating a plasmonic metal and a semiconductor at the nanoscale is of great importance for exploring their optical coupling properties. However, the synthesis and fine structural control of such nanostructures remain challenging. Herein we report the facile aqueous-phase Se-mediated overgrowth of metal selenides onto Au nanocrystals. Taking plasmonic CuSe as an example, the introduction of a Se template allows deposition of large CuSe crystalline grains onto Au nanocrystal seeds in various shapes, including spheres, rods, and plates. Moreover, the configuration of Au-CuSe hybrids can be tuned from core-shell to heterodimer structure by controlling the growth behavior of the Se template. Se overgrowth depends critically on the absorption strength of stabilizers on Au seeds: a strongly absorbing stabilizer inhibits isotropic overgrowth, which is in agreement with molecular dynamics simulations. The resultant Au-CuSe hybrid nanocrystals possess multiple surface plasmon resonance modes. Finally, our synthetic strategy can be extended to prepare other Au-metal selenide hybrids such as Au-AgSe and Au-CdSe with controllable morphologies.
在纳米尺度上整合等离子体金属和半导体对于探索它们的光学耦合性质非常重要。然而,这种纳米结构的合成和精细结构控制仍然具有挑战性。在此,我们报告了在水相环境中通过硒介导的方法在金纳米晶上生长金属硒化物的简便方法。以等离子体 CuSe 为例,引入硒模板可以使各种形状的金纳米晶种子(包括球体、棒体和板体)上沉积大的 CuSe 晶畴。此外,通过控制硒模板的生长行为,可以将 Au-CuSe 杂化结构从核壳结构调谐为异质二聚体结构。硒的外延生长取决于 Au 种子上稳定剂的吸收强度:强吸收稳定剂抑制各向同性外延,这与分子动力学模拟结果一致。所得的 Au-CuSe 杂化纳米晶体具有多种表面等离子体共振模式。最后,我们的合成策略可以扩展到制备其他具有可控形貌的 Au-金属硒化物杂化物,如 Au-AgSe 和 Au-CdSe。