Cubic graphene is an intrinsic semiconductor with hollow geometric structure and entirely sp² hybridization state. In this paper, using first principles calculations, we investigate the phonon transport properties of this novel carbon allotrope. The calculations show that at room temperature the thermal conductivity of cubic graphene is approximately 266.17 W/mK, which is obviously lower than that of diamond with fully sp³ hybridization state (2033 W/mK). Such low thermal conductivity mainly originated from the distorted sp² bond and complex structure which give rise to the flatted and mixed phonon branches as well as strong phonon anharmonicity. Meanwhile, to provide detectable structure fingerprints for experiment, the Raman spectrum and vibrational features of Raman-active phonon modes are also calculated in this work. These results elucidate the intrinsic phonon transport properties of cubic graphene as compared with the case of diamond, and could underpin its potential applications in the field of thermal management.

立方石墨烯是具有空心几何结构和完全sp ²杂交状态的本征半导体。在本文中，使用第一性原理计算，我们研究了这种新型碳同素异形体的声子输运性质。计算表明，在室温下，立方石墨烯的热导率约为266.17 W / mK，明显低于具有完全sp ³杂交状态的金刚石的热导率（2033 W / mK）。如此低的热导率主要源于变形的sp ²键和复杂的结构会导致声子分支扁平和混合以及强声子非调和性。同时，为提供可检测的结构指纹用于实验，还计算了拉曼活性声子模的拉曼光谱和振动特征。这些结果阐明了立方石墨烯与金刚石相比的固有声子输运特性，并有可能支持其在热管理领域的潜在应用。