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Laser interaction with nanoparticles in liquid is the fundamental theoretical basis for many applications but it is still challenging to observe this nanoscale phenomenon within a few nanoseconds in liquid by experiment. The successful implementation of the two-temperature method integrated with molecular dynamics (TTM-MD) in laser interaction with bulk material has shown great potential in providing a panoramic view of the laser interaction with the nanoparticles. However, the current TTM-MD model has to divide the system into cubic cells, which leads to mistakes near the nanoparticle’s surface. We introduce the latest model, which performs the TTM-MD on each individual cluster instead of the cubic cells, and its high-performance parallel cluster analysis algorithm to update the cluster size. The cluster-based TTM-MD revealed the nanoparticle formation mechanism of laser fragmentation in liquid (LFL) and facilitated the study of laser fluence’s effect on the size distribution. In addition to LFL, this model is promising to be implemented in the laser thermal therapy of tumors, laser melting in liquid (LML), etc. Although cluster-based TTM-MD has proven to be a powerful tool for studying laser interaction with nanoparticles, a few challenges and future developments for the cluster-based TTM-MD, especially the ionization induced by femtosecond, are also discussed.

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Hydrogen energy is recognized as the clean energy with the most development potential, and hydrogen fuel cell technology is considered the ultimate solution utilizing hydrogen energy. The proton exchange membrane fuel cell (PEMFC) has the merits of high energy efficiency, high energy density, low operating temperature, is clean, and affords environmental protection. Improving the structure of each functional layer could play a significant role in improving PEMFC performance. In addition, membrane electrode assemblies (MEAs) are the core components of a PEMFC, and their structure includes three main parts, namely, the gas diffusion layer (GDL), catalytic layer (CL), and proton exchange membrane (PEM). Therefore, this review focuses on progress in the modeling and simulation of the material structure in MEAs. First, the GDL simulation models are critically reviewed, including two-phase calculation models and microscopic simulation models. Second, CL microstructure models are comprehensively evaluated, involving power density enhancement, catalyst loading distribution, electrochemical reaction and its performance optimization. Third, the PEM simulation model, relating to molecular dynamics (MD) simulation techniques, 3D numerical techniques, and multiphysics simulation, are reviewed. Finally, the three aspects of similarity, individuality, and complementarity of these simulation models are discussed, and necessary outlooks, including the current limitations and challenges, are suggested, providing a reference for low-cost, high-performing PEMFC membrane electrodes for the future.

Transparent nano-ceramics have an important high-transmittance, material-integrating structure and function and a variety of potential applications, such as use in infrared windows, optical isolators, composite armors, intelligent terminal screens, and key materials of solid-state lasers. Transparent ceramics were originally developed to replace single crystals because of their low fabricating cost, controllable shape, and variable composition. Therefore, this study reviews and summarizes the development trends in transparent nano-ceramics and their potential applications. First, we review the research progress and application of laser nano-ceramic materials, focusing on the influence of controllable doping of rare earth ions on thermal conductivity and the realization of large-scale fabrication technology. Second, the latest research progress on magneto-optical transparent nano-ceramics, mainly including terbium gallium garnet (Tb3Ga5O12, TGG) ceramics and terbium aluminum garnet (Tb3Al5O12, TAG) ceramics, are summarized, and their performance is compared. Third, the research progress of transparent armor nano-ceramic materials, represented by MgAl2O3 and Aluminum oxynitride (AlON), are reviewed. Lastly, the progress in electro-optical transparent nano-ceramics and scintillation transparent nano-ceramics is reported, and the influence of the material-fabrication process on electro-optic effect or luminous intensity is compared. Moreover, the effect of particle diameter on fabrication, the relationship between nano powder and performance, and different sintering methods are discussed. In summary, this study provides a meaningful reference for low-cost and sustainable production in the future.