First-principles insight into Li and Na ion storage in graphene oxide
Zhong Shu-Ying, Shi Jing, Luo Wen-Wei, Lei Xue-Ling
       

Total DOS of GO with O coverages of (a) 12.5% (C8O1), (b) 25% (C8O2), (c) 37.5% (C8O3), and (d) 50% (C8O4). The Fermi levels are set to zero.