Khosravi Azadeh, Fereidoon Abdolhosein, Ahangari Morteza Ghorbanzadeh, Ganji Masoud Darvish, Emami Seyede Negar
Department of Mechanical Engineering, Semnan University, Semnan, Iran.
J Mol Model. 2014 May;20(5):2230. doi: 10.1007/s00894-014-2230-8. Epub 2014 Apr 29.
Ab initio vdW calculations with the DFT level of theory were used to investigate hydrogen (H₂) adsorption on Pt-adsorbed graphene (Pt-graphene). We have explored the most energetically favorable sites for single Pt atom adsorption on the graphene surface. The interaction of H₂ with the energetically favorable Pt-graphene system was then investigated. We found that H₂ physisorbs on pristine graphene with a binding energy of -0.05 eV, while the binding energy is enhanced to -1.98 eV when H₂ binds Pt-adsorbed graphene. We also found that up to four H₂ molecules can be adsorbed on the Pt-graphene system with a -0.74 eV/H₂ binding energy. The effect of graphene layer stretching on the Pt-graphene capacity/ability for hydrogen adsorption was evaluated. Our results show that the number of H₂ molecules adsorbed on the Pt-graphene surface rises to six molecules with a binding energy of approximately -0.29 eV/H₂. Our first-principles results reveal that the Young's modulus was slightly decreased for Pt adsorption on the graphene layer. The first-principles calculated Young's modulus for the H₂-adsorbed Pt-graphene system demonstrates that hydrogen adsorption can dramatically increase the Young's modulus of such systems. As a result, hydrogen adsorption on the Pt-graphene system might enhance the substrate strength.
采用密度泛函理论（DFT）水平的从头算范德华（vdW）计算方法，研究了氢（H₂）在铂吸附的石墨烯（Pt-石墨烯）上的吸附情况。我们探索了石墨烯表面上单铂原子吸附的能量最有利位点。然后研究了H₂与能量有利的Pt-石墨烯体系的相互作用。我们发现，H₂在原始石墨烯上物理吸附的结合能为-0.05 eV，而当H₂与铂吸附的石墨烯结合时，结合能提高到-1.98 eV。我们还发现，在Pt-石墨烯体系上最多可以吸附四个H₂分子，结合能为-0.74 eV/H₂。评估了石墨烯层拉伸对Pt-石墨烯吸附氢的容量/能力的影响。我们的结果表明，吸附在Pt-石墨烯表面的H₂分子数量增加到六个，结合能约为-0.29 eV/H₂。我们的第一性原理结果表明，铂吸附在石墨烯层上时，杨氏模量略有降低。H₂吸附的Pt-石墨烯体系的第一性原理计算杨氏模量表明，氢吸附可以显著提高此类体系的杨氏模量。因此，氢在Pt-石墨烯体系上的吸附可能会增强基底强度。
