## 3 Results  
### Exposure  
Let us first consider the exposure of a single flake at 300 K. Even at this stage of simulation, a difference in the behavior of nanoparticles in contact with a graphene flake simulated with different potentials is observed. As can be seen from Figure 1a, the behavior of a Cu nanoparticle inside GF for the EAM-Morse and Morse potentials is very similar and quite different from that for GF simulated with the BOP potential. When a GF is simulated with the BOP potential, the Cu nanoparticle attracts the sides of graphene, while for a GF simulated with the EAM-Morse and Morse potential, the Cu nanoparticle repulses the sides of the GF. It can also be seen that, with the use of the EAM potential, the Cu nanoparticle preserves the crystalline order better than with the BOP and pure Morse potentials. The Cu nanoparticle inside GF simulated with the BOP potential changes its shape to become more spherical. However, for a single GF it is seen that the interaction of Cu and GF is weaker than within Cu atoms in the nanoparticle and the GF is opened as for the Morse potential.  
From Figure 1b, it can be seen that Cu nanoparticles simulated with BOP are attracted to GFs. In contrast, for composite precursors simulated with the EAM-Morse and Morse potentials, Cu nanoparticles move in opposite directions from GFs, interact with each other or coagulate. For all three cases, GFs open, but for CG-Cu\({}_{BOP}\), GFs with attached Cu nanoparticles can be seen, while, for CG-Cu\({}_{EM}\) and CG-Cu\({}_{M}\), there are graphene layers with coagulated nanoparticles. The behavior of the structure simulated with the BOP potential can be explained by the fact that this potential was developed to investigate the growth of graphene on a copper substrate and, therefore, in this case, the strongest bond between a graphene flake and a copper nanoparticle is expressed [20]. Potential parameters were chosen to reproduce graphene adsorption on Cu and, consequently, the C-Cu interaction is much stronger than the simple van der Waals interaction. Moreover, in contrast to AIREBO used with the EAM-Morse and Morse potentials, the BOP potential results in worse interaction between GFs--the GFs are rotated more randomly during exposure. Use of AIREBO results in the formation of layered structures and more curved GFs.  
As was mentioned in Section 2, the results for one Cu atom and graphene showed a significant difference in the distance between the Cu atom and graphene for the BOP and Morse potentials. It can be concluded that there is no connection to the interaction between one Cu atom with graphene and the interaction of the number of graphene flakes and Cu nanoparticles. We started with simulation of graphene and one Cu atom to obtain a better understanding of this difference. It can initially be concluded that, for separate Cu atoms and one graphene plane, or for a Cu substrate and separate C atoms, it is better to use the BOP potential. However, when we try to understand the complex system composed of crumpled graphene flakes and Cu nanoparticles, we do not need to reproduce such strong adhesion. If we move from a system composed of a Cu atom and graphene to a system composed of nanoparticles and graphene flake, we see very different behavior--nanoparticles do not move so far from the flake. Here, the Morse potential is much more suitable, leading to the conclusion that different potentials can be used to solve different problems.