Hydrothermal growth of Cobalt germanate/reduced graphene oxide nanocomposite as superior anode materials for Lithium-ion batteries

Unique Structural Design and Strategies for Germanium‐Based Anode Materials Toward Enhanced Lithium Storage

“…Graphene is an optimal surface modification choice for germanium-based materials [28,45,58,60,63,64] due to its remarkable mechanical flexibility, electrical conductivity, and open channels for lithium-ion diffusion. It is difficult, however, to thoroughly and uniformly encapsulate germanium particles in graphene sheets during the synthesis.…”

“…Ternary germanium‐based compounds, such as CuGeO 3 , Co 2 GeO 4 , SrGe 4 O 9 , BaGe 4 O 9 , Zn 2 GeO 4 , and Ca 2 Ge 7 O 16 , have been studied for application as anode materials for lithium‐ion batteries. Zn 2 GeO 4 has drawn increasing attentions due to its low cost (only 27% mass percentage of germanium in the compound) .…”

Electrochemical Performance of M2GeO4(M = Co, Fe and Ni) as Anode Materials with High Capacity for Lithium-Ion Batteries

“…The reduction peak at 0.02 V was associated with the alloying reaction of lithium with Ge to form the Li 4.4 Ge phase, as presented in equation 2 [26]. The small and broad oxidation peaks at 0.52 and 1.38 V during anodic scan could be attributed to the dealloying reaction of Li 4.4 Ge into Ge followed by the formation of GeO 2 [24]. The broad peak at a higher potential between 1.80 and 2.50 V elucidates the multiple oxidation reaction of Co 0 to Co 2+ and Co 2+ to Co 3+ [27].…”

“…After the first cycle, the reversible reactions take place according to the electrochemical reactions given in equation 2to (4). The redox peaks observed at 0.02/0.52, 0.82/1.38 and 1.26-1.53/ 1.97-2.22 V correspond to the alloying/de-alloying reaction of Ge, and the conversion reaction of GeO 2 and cobalt oxide, respectively [24]. In Fig.…”

“…3. The Co 2 GeO 4 electrode shows two reduction peaks at 0.78 and 0.37 V in the first cycle, which can be assigned to the disintegration of Co 2 GeO 4 crystal structure into its individual components such as Co, Ge, and the formation of Li 2 O, as given in equation (1) and the electrolyte decomposition [24,25]. The reduction peak at 0.02 V was associated with the alloying reaction of lithium with Ge to form the Li 4.4 Ge phase, as presented in equation 2 [26].…”