The exploration of catalysts for energy conversion lies at the center of sustainable development. The combination of experimental and computational approaches can provide insights into the inner laws between the catalytic performance and the structural and electronic properties of catalysts. Owing to the inherent advantages of 2D materials over their 3D counterparts, including high specific surface area and abundant surface defects that could provide sufficient active sites, 2D materials are promising candidates and have attracted wide interest in catalysis. Importantly, 2D materials are the most widely computationally investigated models with which to relate computational prediction with experimental confirmation conveniently. Recently, more 2D catalysts have been prepared in experiments while more accurate computational methods have been used to disclose catalytic performance, and explore the mechanism at an atomic level. In this review, recent advances are summarized related to the development and design of 2D electro/photocatalysts. The main emphasis is put on the unique properties of 2D catalysts investigated by the combination of experiments and computations. Computational methods closer to experimental environments are introduced with particular attention to bridge the gap between experiments and computations. In addition, the challenges of computations and experiments are also discussed for 2D catalysts.

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A theoretical model which includes considerations of the effects of an interfacial nanolayer formed by liquid molecule layering on the particle/liquid interface and of micro-convection caused by thermal motion of nanoparticles has been proposed to calculate the effective thermal conductivity of nanofluids. This model accounts for the enhancement in effective thermal conductivity of a nanofluid with respect to the suspended nanoparticle size, volume fraction, temperature and thermal conductivities of the nanoparticle and base fluid. The predicted results are in good agreement with some recently available experimental data.

Spray drying method was used to prepare cocrystals of hexanitrohexaazaisowurtzitane (CL-20) and cyclotetramethylene tetranitramine (HMX). Raw materials and cocrystals were characterized using scanning electron microscopy, X-ray diffraction, differential scanning calorimetry, Raman spectroscopy, and Fourier transform infrared spectroscopy. Impact and friction sensitivity of cocrystals were tested and analyzed. Results show that, after preparation by spray drying method, microparticles were spherical in shape and 0.5–5 µm in size. Particles formed aggregates of numerous tiny plate-like cocrystals, whereas CL-20/HMX cocrystals had thicknesses of below 100 nm. Cocrystals were formed by C–H⋯O bonding between –NO2 (CL-20) and –CH2– (HMX). Nanococrystal explosives exhibited drop height of 47.3 cm, and friction demonstrated explosion probability of 64%. Compared with raw HMX, cocrystals displayed significantly reduced mechanical sensitivity.

To improve the safety of RDX (hexogen), an energetic polymer (HP‐1) was introduced to coat RDX with 2,4,6‐trinitrotoluene (TNT) by combining the solvent–nonsolvent and the aqueous suspension‐melting method. Scanning electron microscope (SEM), transmission electron microscope (TEM), and X‐ray photoelectron spectrometry (XPS) were employed to characterize the samples, and the role of HP‐1 in the coating process was discussed. The impact sensitivity, friction sensitivity, and the thermal stability of unprocessed and coated RDX were investigated, and the explosion heat of samples was also estimated. Results indicate that HP‐1 improves the wetting ability of the liquid coating material on RDX surface and reinforces the connection between RDX and the coating material. By surface coating, the impact and friction sensitivity of RDX decrease obviously; the drop height (H50) is increased from 37.2 to 58.4 cm, and the friction probability is reduced from 92 to 38%. The activation energy (E) and the self‐ignition temperature increase by 10457.38 J⋅mol−1 and 1.8 K, respectively. The explosion heat is reduced merely by 0.93%.

Ultrafine hexanitrohexaazaisowurtzitane (CL‐20) samples were prepared by a ultrasound‐ and spray‐assisted precipitation method. Raw CL‐20 and ultrafine CL‐20 samples were characterized by SEM, FT‐IR spectroscopy, XRD, and particle size analysis. The impact sensitivity and thermal stability of two CL‐20 samples were also tested and compared. The results indicate that by this recrystallization process, the mean particle size of CL‐20 is 470 nm, and the particle size distribution was in the range from 400–700 nm. The particle morphology is nearly spheric with a smooth surface. Compared with raw CL‐20, the impact sensitivity of the ultrafine sample is significantely reduced and the drop height (H50) is increased from 12.8 to 37.9 cm. The critical explosion temperature of ultrafine CL‐20 decreased from 235.6 to 229.0 °C, which suggests that the thermal stability of ultrafine CL‐20 is lower than that of raw CL‐20.