New ordered 3D NPG materials will realize better refrigeration systems based on the new operating principle with a uniform hierarchical structure (nm-to-mm scale) and resilience against deformation upon pressurization during the refrigeration cycle. A major impediment to efficient RMPTA systems is the uneven deformation of porous carbon materials under external pressurization. As shown in Fig. , a sharp drop in temperature is observed during the compulsive liquid-gas phase transition upon pressurization, whereas nearly no heating is discernible despite the total recovery of the gas-phase pressure upon release. This irreversibility could be owing to the lack of local structural robustness toward nonuniform stress. The uneven and irreversible structural changes in the nanopores are partly attributed to the structural heterogeneity of the NPGs owing to the inheritance of the irregular secondary particle structure appearing in their template materials, such as Al2O3 and zeolites. Other issue is the low thermal conductivity, and uniform nanographene growth in NPGs can also be achieved through improved CVD chemistry (Fig. ).