Aggregation modeling of the influence of pH on the aggregation of variably charged nanoparticles

AbstractThe aggregation of variably charged nanoparticles is usually induced by the changes in internal and external conditions, such as solution temperature, pH, particle size, van der Waals force, and electrostatic repulsion among particles. In order to explore the effect of pH on the aggregation of variable charge nanoparticles, this paper proposed an extended model based on the 3D on-lattice Cluster–Cluster Aggregation (CCA) model. The extended model successfully established the relationship between pH and sticking probability, and used Smoluchowski theory to calculate the aggregation rate of nanoparticles. The simulation results showed that: (1) the change of the aggregation rate of the variable charge nanoparticles with pH conforms to the Gaussian distribution, (2) the initial particle concentration has a significant effect on the aggregation rate of the nanoparticles, and (3) pH can affect the competition between van der Waals force and electrostatic repulsion between particles, thereby affecting the degree of openness of clusters. The research demonstrated the extended CCA model is valuable in studying the aggregation of the variably charged nanoparticles via transforming the corresponding influence factors into the influence on the sticking probability.

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Aggregation modeling of the influence of pH on the aggregation of variably charged nanoparticles

10.21203/rs.3.rs-670340/v1 ◽

2021 ◽

Author(s):

Yu Xiong ◽

Hailing Xiong

Keyword(s):

Van Der Waals ◽

Influence Factors ◽

Van Der Waals Force ◽

Sticking Probability ◽

Solution Temperature ◽

Electrostatic Repulsion ◽

Extended Model ◽

Aggregation Rate ◽

Variable Charge ◽

Charged Nanoparticles

Abstract The aggregation of variably charged nanoparticles is usually induced by the changes in internal and external conditions, such as solution temperature, pH, particle size, van der Waals force, and electrostatic repulsion among particles. In order to explore the effect of pH on the aggregation of variable charge nanoparticles, this paper proposed an extended model based on the 3D on-lattice Cluster-Cluster Aggregation (CCA) model. The extended model successfully established the relationship between pH and sticking probability, and used Smoluchowski theory to calculate the aggregation rate of nanoparticles. The simulation results showed that: (1) the change of the aggregation rate of the variable charge nanoparticles with pH conforms to the Gaussian distribution, (2) the initial particle concentration has a significant effect on the aggregation rate of the nanoparticles, and (3) pH can affect the competition between van der Waals force and electrostatic repulsion between particles, thereby affecting the degree of openness of clusters. The research demonstrated the extended CCA model is valuable in studying the aggregation of the variably charged nanoparticles via transforming the corresponding influence factors into the influence on the sticking probability.

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First direct measurement of van der Waals force

AccessScience ◽

10.1036/1097-8542.br0718131 ◽

2015 ◽

Keyword(s):

Direct Measurement ◽

Van Der Waals ◽

Van Der Waals Force

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FLUCTUATION-INDUCED RADIATIVE HEAT TRANSFER AND VAN DER WAALS FORCE FOR SPHERICAL SHAPES

Proceeding of First Thermal and Fluids Engineering Summer Conference ◽

10.1615/tfesc1.fnd.012853 ◽

2016 ◽

Author(s):

Yi Zheng ◽

Alok Ghanekar

Keyword(s):

Heat Transfer ◽

Radiative Heat Transfer ◽

Radiative Heat ◽

Van Der Waals ◽

Van Der Waals Force

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First-Principles Study on Graphene/Mg2Si Interface of Selective Laser Melting Graphene/Aluminum Matrix Composites

Metals ◽

10.3390/met11060941 ◽

2021 ◽

Vol 11 (6) ◽

pp. 941

Author(s):

Zhanyong Zhao ◽

Shijie Chang ◽

Jie Wang ◽

Peikang Bai ◽

Wenbo Du ◽

...

Keyword(s):

Interfacial Energy ◽

First Principles ◽

Lattice Mismatch ◽

Van Der Waals ◽

Aluminum Matrix ◽

Van Der Waals Force ◽

Aluminum Matrix Composites ◽

Matrix Composites ◽

Charge Density Difference ◽

Interface Charge

The bonding strength of a Gr/Mg2Si interface was calculated by first principles. Graphene can form a stable, completely coherent interface with Mg2Si. When the (0001) Gr/(001) Mg2Si crystal plane is combined, the mismatch degree is 5.394%, which conforms to the two-dimensional lattice mismatch theory. At the interface between Gr/Mg2Si, chemical bonds were not formed, there was only a strong van der Waals force; the interfaces composed of three low index surfaces (001), (011) and (111) of Mg2Si and Gr (0001) have smaller interfacial adhesion work and larger interfacial energy, the interfacial energy of Gr/Mg2Si is much larger than that of α-Al/Al melt and Gr/Al interfacial (0.15 J/m2, 0.16 J/m2), and the interface distance of a stable interface is larger than the bond length of a chemical bond. The interface charge density difference diagram and density of states curve show that there is only strong van der Waals force in a Gr/Mg2Si interface. Therefore, when the Gr/AlSi10Mg composite is stressed and deformed, the Gr/Mg2Si interface in the composite is easy to separate and become the crack propagation source. The Gr/Mg2Si interface should be avoided in the preparation of Gr/AlSi10Mg composite.

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