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   https://doi.org/10.1039/D0RA03579C  

   Park, J.; Yang, X.; Wickramasinghe, D.; Sundhoro, M.; Orbey, N.; Chow, Kwok-Fan; Yan, M. (January 2020, RSC advances)
2. Crystallization and melting of polymer chains on graphene and graphene oxide

   https://doi.org/10.1039/D3NR00817G  

   Ghasemi, Arman; Liao, Yangchao; Li, Zhaofan; Xia, Wenjie; Gao, Wei (July 2023, Nanoscale)

   This study employs all-atomistic (AA) molecular dynamics (MD) simulations to investigate the crystallization and melting behavior of polar and nonpolar polymer chains on monolayers of graphene and graphene oxide (GO). Polyvinyl alcohol (PVA) and polyethylene (PE) are used as representative polar and nonpolar polymers, respectively. A modified order parameter is introduced to quantify the degree of two-dimensional (2D) crystallization of polymer chains. Our results show that PVA and PE chains exhibit significantly different crystallization behavior. PVA chains tend to form a more rounded, denser, and folded-stemmed lamellar structure, while PE chains tend to form an elongated straight pattern. The presence of oxidation groups on the GO substrate reduces the crystallinity of both PVA and PE chains, which is derived from the analysis of modified order parameter. Meanwhile, the crystallization patterns of polymer chains are influenced by the percentage, chemical components, and distribution of the oxidation groups. In addition, our study reveals that 2D crystalized polymer chains exhibit different melting behavior depending on their polarity. PVA chains exhibit a more molecular weight-dependent melting temperature than PE chains, which have a lower melting temperature and are relatively insensitive to molecular weight. These findings highlight the critical role of substrate and chain polarity in the crystallization and melting of polymer chains. Overall, our study provides valuable insights into the design of graphene-based polymer heterostructures and composites with tailored properties. 

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3. Spontaneous adsorption of ions on graphene at the electrolyte–graphene interface

   https://doi.org/10.1063/5.0023191  

   Sun, Jianbo; Camilli, Luca; Caridad, José M.; Santos, Jaime E.; Liu, Yuxin (November 2020, Applied Physics Letters)

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4. Discovery of Graphene‐Water Membrane Structure: Toward High‐Quality Graphene Process

   https://doi.org/10.1002/advs.202201336  

   Okmi, Aisha; Xiao, Xuemei; Zhang, Yue; He, Rui; Olunloyo, Olugbenga; Harris, Sumner B.; Jabegu, Tara; Li, Ningxin; Maraba, Diren; Sherif, Yasmeen; et al (January 2022, Advanced Science)
5. In-plane thermoelectric properties of graphene/xBN/graphene van der Waals heterostructures

   https://doi.org/10.1088/1361-648X/acb89e  

   Makumi, Sylvester W.; Bem, Daniel; Musila, Nicholas; Foss, Cameron J; Aksamija, Zlatan (February 2023, Journal of Physics: Condensed Matter)

   2D materials have attracted broad attention from researchers for their unique electronic proper-ties, which may be been further enhanced by combining 2D layers into vertically stacked van der Waals heterostructures. Among the superlative properties of 2D systems, thermoelectric energy (TE) conversion promises to enable targeted energy conversion, localized thermal management, and thermal sensing. However, TE conversion efficiency remains limited by the inherent tradeoff between conductivity and thermopower. In this paper, we use first-principles calculation to study graphene-based van der Waals heterostructures (vdWHs) composed of graphene layers and hexagonal boron nitride (h-BN). We compute the electronic band structures of heterostructured systems using Quantum Espresso and their thermoelectric (TE) properties using BoltzTrap2. Our results have shown that stacking layers of these 2D materials opens a bandgap, increasing it with the number of h-BN interlayers, which significantly improves the power factor (PF). We predict a PF of ~1.0x10 11 W/K 2 .m.s for the vdWHs, nearly double compared to 5x10 10 W/K 2 .m.s that we obtained for single-layer graphene. This study gives important information on the effect of stacking layers of 2D materials and points toward new avenues to optimize the TE properties of vdWHs. 

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