Graphene-based derivatives with covalent functionalization and well-defined stoichiometry are highly desirable in view of their application as functional surfaces. Here, we have evaluated by ab initio calculations the energy of formation and the phase diagram of hydroxylated graphane structures, i.e., fully functionalized graphene derivatives coordinated with –H and –OH groups. We compared these structures to different hydrogenated and non-hydrogenated graphene oxide derivatives, with high level of epoxide and hydroxyl groups functionalization. Based on our calculations, stable phases of hydroxylated graphane with low and high contents of hydrogen are demonstrated for high oxygen and hydrogen partial pressure, respectively. Stable phases of graphene oxide with a mixed carbon hybridization are also found. Notably, the synthesis of hydroxylated graphane has been recently reported in the literature.

中文翻译：

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一个从头羟基化石墨烷的研究

考虑到它们作为功能性表面的应用，非常需要具有共价官能化和定义明确的化学计量的基于石墨烯的衍生物。在这里，我们通过从头算起进行了评估计算羟基化石墨烷结构的形成能和相图，即与–H和–OH配位的完全官能化的石墨烯衍生物。我们将这些结构与不同的氢化和非氢化氧化石墨烯衍生物进行了比较，这些衍生物具有高水平的环氧和羟基官能团。根据我们的计算，分别针对高氧分压和高氢分压证明了氢含量低和高的羟基化石墨烷的稳定相。还发现了具有混合碳杂化的氧化石墨烯的稳定相。值得注意的是，最近在文献中已经报道了羟基化石墨烷的合成。