The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adma.202105178.-1), the batteries still exhibit ≈80% capacity retention over 100 cycles, showing great potential for practical application.

Bimetallic phosphides have been identified as promising alternative electrode materials owing to their admirable conductivity and electrochemical activity.

In this study, simulations of dissipative particle dynamics (DPD) were 1 employed to investigate the efficiency of polyether demulsifiers, substituting 2 polyoxypropylene (PPO) hydrophobic blocks for polybutylene oxide (PBO) and 3 polytetrahydrofuran (PTF) in ultra-heavy crude oil emulsions. The simulation results 4 showed that the demulsifiers with polybutylene oxide (PBO) hydrophobic blocks 5 favor high level of demulsification while the demulsifiers with polyoxypropylene 6 (PPO) hydrophobic blocks exhibit better dehydration rates. The kinetics equation 7 demonstrates that the demulsification process is controlled by the combination of 8 flocculation and coalescence. As time progresses, the rate-controlling process of 9 demulsification changes from coalescence controlled to flocculation controlled. 10 Moreover, high performance demulsifiers which have higher rate constants for 11 coalescence could accelerate the rate of drainage of the film much faster, thereby 12 promoting coalescence. The root mean square end-to-end distance 〈R〉 for 13 demulsifiers continues to grow with time, such that their configurations become more 14 stretched. This results to interface arraying and demulsifiers build up a continuous 15 open network which leads to a higher possibility of droplet-droplet coalescence. The 16 variation in radial distribution function (RDF) indicates that there is a rather strong 17 and remarkably structured interaction between asphaltenes and demulsifiers,

Thermoresponsive microgels with a hollow capsule architecture have been widely used in drug delivery and molecular encapsulation, and their efficacy is contingent on the internal structure in the deswelling dynamics process. Despite a large number of experimental studies on microgels, proper theoretical methods based on an individual microgel capsule are still a few because of the complexity of the microgels. Herein, we first propose a novel methodology to investigate the structural properties and deswelling dynamics of microgel capsules by integrating a temperature-dependent Morse potential with Langevin dynamics simulation. Different properties, including volume phase transition temperature, temperature-dependent diameter, and structural morphologies of individual microgels, are assessed to rationalize our simulation method, and a good agreement between simulation predictions and experimental observations has been obtained. Depending on the system temperature, the morphological transition of three regimes in the shell structure is identified: scattered nanogels, progressively porous sponge gels, and dense ribbonlike gels. The temperature-switchable sensors composed of microgel capsules on the substrates are devised, which exhibit tunable reflectivity or thickness by simply varying the system temperature. Our mesoscale results provide helpful insights into the transient structure within the networked microgels and the design of smart polymeric nanomaterials, such as biosensors, drug delivery systems, and actuators.

In this paper, dissipative particle dynamics simulations are performed to study the interfacial and emulsion stabilizing properties of various systems of amphiphilic nanosheets (ANs) self-assembled at the oil/water (O/W) interface. The ANs have a dimensional symmetry structure that encompasses a triangular-plate at the center and two soft comb-like shells constructed with hydrophilic and hydrophobic polymers. As the simulation results show, the AN molecules are highly oriented in interfacial films with their triangular nanosheets parallel to the O/W interface, while their hydrophobic and hydrophilic segments attempt to immerse into the oil phase and aqueous phase, respectively. These results reveal that the rotation of ANs at oil/water interfaces is greatly restricted, meanwhile, their nanosheet (or planar) configuration facilitates their favorable orientation thereby, thus making the emulsion more stable. At higher concentrations, a wrapped-like or micelle morphology is observed. The O/W emulsions stabilized by ANs were also simulated, and it is interesting to find AN 'patches' at the O/W interface which resembles the leather patches on a football. By introducing the "amphiphilic nanosheet balance" concept, the hydrophilic-lipophilic balance (HLB) values of ANs were calculated. Due to their properties of two-dimensional symmetry, the HLB values of ANs tend to approximately 1 which reveals a stronger stability for emulsions.

In the present work, the effects of shear fields on the aggregation of asphaltene molecules in heptane were investigated by means of dissipative particle dynamics simulations. The geometries of asphaltene aggregates without shear fields were studied, and the simulation results provide an interpretation of the experimental results on the microscopic level. The effects of shear fields on asphaltene aggregates were also investigated by accessing the radial distribution functions, spatial orientation correlation functions, and the radii of gyrations. We show that the shear fields can destroy the conformational order of the aggregates by damaging the organized structure and isolating the asphaltenes. As the radius of gyration results show, the asphaltene molecules are elongated to be alike-polymers by shear fields. Moreover, the reason why the viscosity decreases under shear fields is that the shear fields lead to the increase of dimerization free energies.

Emulsions with interface-active components at the water/oil (w/o) interface are of fundamental and practical interest in many fields. Here we investigate the interfacial films of asphaltenes and asphaltenes/polyacrylamide (PAM) at the w/o interface of water-in-crude oil emulsions. With the combination of the dissipative particle dynamics simulation and experimental observation, the molecular interactions of asphaltenes and asphaltenes/PAM at the w/o interface are extensively analyzed. We show that the rigid mechanical film of asphaltenes originates from a rigid structure of polycyclic aromatic hydrocarbons (PAHs) and the π–π bonding interactions between the PAHs of asphaltenes, and at a higher concentration of asphaltenes, the nanoaggregates of asphaltenes, acting as a space fortress at the w/o interface, make the drop–drop coalescence more difficult. In addition, a layer-by-layer assembled architecture film of asphaltenes/polyacrylamide formed at the w/o interface is identified, and we observe that the inner layer is composed of PAM with a network structure and the outer layer is composed of rigid asphaltenes. While the rigidity and stability of this film are attributed to the viscoelasticity and rheology of PAM and the “synergy effect” between asphaltenes and PAM, its presence greatly enhances the stability of water-in-oil emulsions. We further conclude that PAM with higher concentrations and molecular weights can generate a more ordered network structure, leading to a more stable asphaltenes/PAM film at the w/o interface. This combined study provides helpful insight into the demulsification of water-in-oil emulsion.

The dissipative particle dynamics (DPD) method is used to investigate the adsorption behavior of PEO-PPO-PEO triblock copolymers at the liquid/solid interface. The effect of molecular architecture on the self-assembled monolayer adsorption of PEO-PPO-PEO triblock copolymers on hydrophobic surfaces is elucidated by the adsorption process, film properties, and adsorption morphologies. The adsorption thicknesses on hydrophobic surfaces and the diffusion coefficient as well as the aggregation number of Pluronic copolymers in aqueous solution observed in our simulations agree well with previous experimental and numerical observations. The radial distribution function revealed that the ability of self-assembly on hydrophobic surfaces is P123 > P84 > L64 > P105 > F127, which increased with the EO ratio of the Pluronic copolymers. Moreover, the shape parameter and the degree of anisotropy increase with increasing molecular weight and mole ratio of PO of the Pluronic copolymers. Depending on the conformation of different Pluronic copolymers, the morphology transition of three regimes on hydrophobic surfaces is present: mushroom or hemisphere, progressively semiellipsoid, and rectangle brush regimes induced by decreasing molecular weight and mole ratio of EO of Pluronic copolymers.