Metal nanomaterials with high thermal conductivity are ideal promoters for enhanced gas hydrate formation, including metal?based nanoparticles, metal oxides, and metalloid oxides. In this paper, the effects of different kinds of metal nanomaterials on the formation of gas hydrates were reviewed, and the effects of parameters such as the induction time and gas consumption of enhanced hydrate formation were introduced from the three aspects of additive concentration, particle size and surface properties. The results show that the heat transfer effect of metal?based nanoparticles is better, and some metal oxides and metalloid oxides will exhibit an inhibitory effect; the appropriate addition concentration and particle size have an important impact on the formation of hydrates. In addition, the combination of metal nanomaterials and chemical reagents can significantly improve the dispersion stability of nanoparticles, thereby promoting the efficient generation of hydrates.

As the greenhouse effect becomes gradually significant, CO₂ capture and storage (CCS) has turned into a potential emission reduction measure, and the adsorption method of CO₂ capture is one of the most promising technologies. Porous solid adsorbents have attracted widespread attention due to their excellent CO₂ adsorption performance. This review focused on the research of CO₂ removal by adsorption. Five different adsorption materials were introduced, and the main factors affecting CO₂ adsorption were summarized, as well as the adsorption performance of modified materials. The results show that the changes of temperature, pressure, and pore structure can affect the physical adsorption properties of the materials; reduction, oxidation, and metal ion loading modification can improve the CO₂ adsorption performance by Changing the type or number of functional groups on the surface of the material.

The sol?gel method was used to modify the multi?walled carbon nanotubes, so that SnO₂ was combined with MWCNTs and doped with Cu ions. The samples M, M+Cu, M+Sn, and M+Sn+Cu were characterized by SEM, XRD, and FTIR. The surface microstructure was analyzed. The static adsorption method was used to measure the saturated adsorption capacity of different samples to VOCs. The VOCs gas volume concentration, temperature, and effects of metal doping were analyzed respectively. The results show that the saturation adsorption capacity of the four adsorbent samples is linearly related to the volume concentration and temperature of VOCs, and the larger the value of the two samples, the smaller the saturation adsorption capacity; at normal temperature (25 ℃) and normal pressure, MWCNTs adsorption capacity is almost 0, the saturation adsorption capacity of M+Cu is slightly smaller than M+Sn, and the adsorption capacity of M+Sn+Cu is about twice of M+Sn, up to 37.4 mg/g.