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Updated: May 16, 2026

A Standard and Reliable Method to Fabricate Two-Dimensional Nanoelectronics
Published on: August 28, 2018
Two viable three-dimensional carbon semiconductors with an entirely sp2 configuration
Chaoyu He1, Lizhong Sun, Chunxiao Zhang
1Laboratory for Quantum Engineering and Micro-Nano Energy Technology, Xiangtan University, Xiangtan 411105, China.
Abstract:
Using the first-principles method, we investigate the energetic stability, dynamic stability and electronic properties of two viable three-dimensional (3D) carbon semiconductors with an entirely sp(2) configuration, sp(2)-diamond and cubic-graphite. Both allotropes are more stable than the previously proposed K4-carbon and T-carbon and were confirmed to be dynamically stable. Interestingly, sp(2)-diamond and cubic-graphite behave as semiconductors, which is contrary to previously proposed all-sp(2) metallic carbons. sp(2)-Diamond is a semiconductor with a direct band gap of 1.66 eV and cubic-graphite is an indirect semiconductor with a band gap of 2.89 eV. Further studies show that both sp(2)-diamond and cubic-graphite possess structural all-sp(2) configurations but not electronic sp(2) hybridizations. The very low densities and entirely sp(2) configurations of sp(2)-diamond and cubic-graphite can be potentially applied in hydrogen-storage, photocatalysts and molecular sieves.
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