Photoinduced nanobubble-driven superfast diffusion of nanoparticles imaged by 4D electron microscopy.
Photoinduced nanobubble-driven superfast diffusion of nanoparticles imaged by 4D electron microscopy.
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通过4D电子显微镜成像的纳米颗粒的光诱导的纳米驱动的超快速扩散。
DOI：
10.1126/sciadv.1701160
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发表时间：
2017-08
期刊：
影响因子：
13.6
通讯作者：
Zewail AH
中科院分区：
文献类型：
--
作者：
Fu X;Chen B;Tang J;Zewail AH
由光诱导纳米气泡驱动的超快弹道和扩散金纳米粒子的直接可视化。非平衡状态下的主动或推进布朗粒子的动力学最近引起了包括人造微/纳米电机和生物实体在内的许多领域的极大兴趣。了解它们的动态可以深入了解远离平衡的物理和生物系统的统计特性。我们报告了通过具有高时空分辨率的液池四维电子显微镜（4D-EM）成像的光子激活金纳米颗粒（NP）在水中的平移动力学。在飞秒激光脉冲的激发下，我们观察到这些纳米粒子表现出超快的扩散平移，其扩散常数比没有激光激发时大四到五个数量级。测量的扩散常数分别遵循对激光注量的幂律依赖性以及随激光重复率的线性增加。纳米颗粒的这种超快扩散是由纳米颗粒表面附近的光诱导蒸汽纳米气泡（NB）产生的强大随机驱动力引起的。相比之下，纳米粒子在低至纳秒的短时间内表现出超快的弹道平移。结合物理模型模拟，本研究揭示了用于推进运动的光诱导NB推进机制，为更好地设计光激活人造微/纳米电机提供了物理见解。液体细胞 4D-EM 还提供了研究其原生环境中其他数值动力学行为的潜力。
Direct visualization of superfast ballistic and diffusive gold nanoparticles driven by photoinduced nanobubbles. Dynamics of active or propulsive Brownian particles in nonequilibrium status have recently attracted great interest in many fields including artificial micro/nanoscopic motors and biological entities. Understanding of their dynamics can provide insight into the statistical properties of physical and biological systems far from equilibrium. We report the translational dynamics of photon-activated gold nanoparticles (NPs) in water imaged by liquid-cell four-dimensional electron microscopy (4D-EM) with high spatiotemporal resolution. Under excitation of femtosecond laser pulses, we observed that those NPs exhibit superfast diffusive translation with a diffusion constant four to five orders of magnitude greater than that in the absence of laser excitation. The measured diffusion constant follows a power-law dependence on the laser fluence and a linear increase with the laser repetition rate, respectively. This superfast diffusion of the NPs is induced by a strong random driving force arising from the photoinduced steam nanobubbles (NBs) near the NP surface. In contrast, the NPs exhibit a superfast ballistic translation at a short time scale down to nanoseconds. Combining with a physical model simulation, this study reveals a photoinduced NB propulsion mechanism for propulsive motion, providing physical insights into better design of light-activated artificial micro/nanomotors. The liquid-cell 4D-EM also provides the potential of studying other numerical dynamical behaviors in their native environments.
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影响因子：
2.9
作者：
Dou, YS;Zhigilei, LV;Garrison, BJ
通讯作者：
Garrison, BJ
影响因子：
1.6
作者：
Erdmann, U;Ebeling, W;Schweitzer, F
通讯作者：
Schweitzer, F
影响因子：
38.3
作者：
Lukianova-Hleb, Ekaterina Y.;Kim, Yoo-Shin;Lapotko, Dmitri O.
通讯作者：
Lapotko, Dmitri O.
影响因子：
17.1
作者：
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通讯作者：
Cichos, Frank
影响因子：
8.6
作者：
Cohen, AE
通讯作者：
Cohen, AE