How Implementation of Entropy in Driving Structural Ordering of Nanoparticles Relates to Assembly Kinetics: Insight into Reaction-Induced Interfacial Assembly of Janus Nanoparticles
How Implementation of Entropy in Driving Structural Ordering of Nanoparticles Relates to Assembly Kinetics: Insight into Reaction-Induced Interfacial Assembly of Janus Nanoparticles
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熵在驱动纳米颗粒结构排序中的实现如何与组装动力学相关：深入了解反应诱导的 Janus 纳米颗粒界面组装
DOI：
10.1021/acs.langmuir.8b01378
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发表时间：
2018
期刊：
影响因子：
3.9
通讯作者：
Yan Li-Tang
中科院分区：
文献类型：
--
作者：
Yang Ye;Chen Pengyu;Cao Yufei;Huang Zihan;Zhu Guolong;Xu Ziyang;Dai Xiaobin;Chen Shi;Miao Bing;Yan Li-Tang
理解和利用熵对有序转变的贡献的能力对于具有良好控制结构的自组装系统的设计至关重要。然而，人们对组装动力学在熵驱动相行为中的作用知之甚少。在这里，通过结合计算机模拟和理论分析，我们报告说，驱动相变的熵的实现很大程度上取决于新设计的纳米粒子系统的反应诱导自组装的动力学过程。特别是，此类系统在流体-流体界面处包含二元 Janus 纳米颗粒，并经历由熵驱动的相变，并由仅纳米颗粒一种成分的表面引发的聚合反应控制。我们的模拟表明，反应速率和纳米颗粒扩散动力学之间的竞争控制着熵的实现，驱动这些界面纳米颗粒混合物中从随机混合相到插层相的相变，从而导致不同的动力学途径。在低反应速率下，该转变表现出混合参数的突然跳跃，类似于一阶平衡相变。增加反应速率会减少跳跃，直到转变变得连续，表现为类似二阶的相变，其中可以识别表征转变的临界指数。我们最终开发了聚合物链斑点理论的分析模型，以补充模拟结果并揭示熵驱动相行为的基本标度定律。实际上，我们的结果提供了进一步的机会，通过动力学控制来放大熵对材料设计的贡献。
The ability to understand and exploit entropic contributions to ordering transition is of essential importance in the design of self-assembling systems with well-controlled structures. However, much less is known about the role of assembly kinetics in entropy-driven phase behaviors. Here, by combining computer simulations and theoretical analysis, we report that the implementation of entropy in driving phase transition significantly depends on the kinetic process in the reaction-induced self-assembly of newly designed nanoparticle systems. In particular, such systems comprise binary Janus nanoparticles at the fluid–fluid interface and undergo phase transition driven by entropy and controlled by the polymerization reaction initiated from the surfaces of just one component of nanoparticles. Our simulations demonstrate that the competition between the reaction rate and the diffusive dynamics of nanoparticles governs the implementation of entropy in driving the phase transition from randomly mixed phase to intercalated phase in these interfacial nanoparticle mixtures, which thereby results in diverse kinetic pathways. At low reaction rates, the transition exhibits abrupt jump in the mixing parameter, in a similar way to first-order, equilibrium phase transition. Increasing the reaction rate diminishes the jumps until the transitions become continuous, behaving as a second-order-like phase transition, where a critical exponent, characterizing the transition, can be identified. We finally develop an analytical model of the blob theory of polymer chains to complement the simulation results and reveal essential scaling laws of the entropy-driven phase behaviors. In effect, our results allow for further opportunities to amplify the entropic contributions to the materials design via kinetic control.