Surface Structure and Interaction of Surface/Interface Probed by Mesoscale Simulations and Experiments

Heterogenous catalysis, fluid transportation, wetting, nanofriction, and protein adsorption are important phenomena in chemical and biological engineering. Mesoporous materials show great prospect in heterogenous catalysis. However, the reaction and transport in mesopores differ from that in the macroscale, so the complicated structure and intra-/interaction of the interface must be clarified to reveal the mechanism of regulation. Wetting is of key importance for many applications. Ionic liquids (ILs) are a new promising class of lubricants; its performance strongly depends on the wetting behavior at interface. The frictional properties of thin films depend on the film packing density, structure, and crystallinity. Protein adsorption onto surfaces is fundamental for the development of low-fouling surfaces, protein immobilization, and protein separations. The adsorbed proteins act as an intermediary between the implanted material and the surrounding tissues, subsequently influencing the host responses. Therefore, surface repellence to protein is critical for the development of advanced biomaterials. These microscopic phenomena cannot be accurately analyzed by only using simple experiment. Using molecular simulation, it has been found that the flow of polar liquid on the surface of TiO₂ can be improved significantly. Coupling different simulation methods is needed to consider the behavior of fluid on rough interface with reaction. We can investigate the reaction mechanism and the relationship between changes of the composition quantitatively, using ReaxFF method that considers reaction and transition simultaneously for a large system. Due to a greater impact of interfacial roughness on the stability of the catalytic, the new method "interface coarse-grained mesoscopic simulation" should be adopted. Because of the large size of the protein molecule, mesoscale approaches are needed. Researchers used coarse-grained simulation methods to study its adsorption and interfacial behavior and obtained a lot of results. Atomic force microscopy (AFM) can be used to measure the force of clusters or fluids on surfaces with different roughness in mesoscopic directly and then draw the law of interface behaviors. People can establish the relationship between AFM measurement results and coarse-grained force field; it is expected to become a powerful medium-scale method to promote the study of the current mesoscale phenomena and mechanisms.