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Flask-like Janus Colloidal Motors with Explicit Direction and Tunable Speed
Yingchun Long1,2, Qiuhua Wu2, Xiuyuan Zuo1,2
1Department of Chemical Engineering, Tsinghua University, Beijing100084, P.R. China.
ACS Nano
|October 17, 2022
Summary
Researchers developed flask-like Janus particles (FJPs) with controlled neck lengths. These anisotropic nanoparticles, loaded with platinum (Pt), function as efficient colloidal motors with tunable speeds and directionality.
Area of Science:
- Materials Science
- Nanotechnology
- Colloidal Science
Background:
- Anisotropic nanoparticles with controlled morphology and composition are crucial for diverse applications.
- Precisely regulating nanoparticle growth and final shape remains a significant challenge in materials science.
Purpose of the Study:
- To fabricate flask-like Janus particles (FJPs) with controllable neck lengths and segmented compositions.
- To investigate the influence of tunable neck length on the performance of FJPs as colloidal motors.
Main Methods:
- Sol-gel process utilizing different silane precursors to synthesize FJPs.
- Selective loading of platinum (Pt) catalyst into the cavities of FJPs.
- Characterization of FJP morphology and catalytic activity.
Main Results:
- Flask-like Janus particles (FJPs) with tunable neck lengths were successfully synthesized.
- Platinum (Pt) catalyst was selectively loaded into the FJP cavities.
- The resulting FJPs@Pt demonstrated explicit directionality and tunable speeds as colloidal motors, with a maximum diffusion coefficient of 18.2 μm² s⁻¹.
Conclusions:
- The sol-gel method provides precise control over FJP morphology, particularly neck length.
- Tunable neck length in FJPs directly impacts their performance as anisotropic colloidal motors.
- These engineered FJPs offer a promising platform for developing advanced nanomachinery.
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