Doped Graphene Sheets As Anode Materials with Superhigh Rate and Large Capacity for Lithium Ion Batteries

Abstract

One great challenge in the development of lithium ion batteries is to simultaneously achieve high power and large energy capacity at fast charge and discharge rates for several minutes to seconds. Here we show that nitrogen- or boron-doped graphene can be used as a promising anode for high-power and high-energy lithium ion batteries under high-rate charge and discharge conditions. The doped graphene shows a high reversible capacity of >1040 mAh g(-1) at a low rate of 50 mA g(-1). More importantly, it can be quickly charged and discharged in a very short time of 1 h to several tens of seconds together with high-rate capability and excellent long-term cyclability. For example, a very high capacity of ∼199 and 235 mAh g(-1) was obtained for the N-doped graphene and B-doped graphene at 25 A g(-1) (about 30 s to full charge). We believe that the unique two-dimensional structure, disordered surface morphology, heteroatomic defects, better electrode/electrolyte wettability, increased intersheet distance, improved electrical conductivity, and thermal stability of the doped graphene are beneficial to rapid surface Li(+) absorption and ultrafast Li(+) diffusion and electron transport, and thus make the doped materials superior to those of pristine chemically derived graphene and other carbonaceous materials.

B, N Codoped and Defect‐Rich Nanocarbon Material as a Metal‐Free Bifunctional Electrocatalyst for Oxygen Reduction and Evolution Reactions

“…A new peak observed at 397.6 eV for B,N‐carbon can be attributed to the N—B bond 42, 43. For B 1S, three B‐containing species can be clearly observed for B‐carbon, which are corresponded to the BC 3 (190.2 eV), BC 2 O (191.1 eV), and BCO 2 (192.3 eV) groups,14, 15, 44 while a new deconvoluted peak observed at 190.7 eV for B,N‐carbon is attributed to the B—N bond 42, 43, 45, 46, 47. Based on the above analyses, B and N heteroatoms are successfully introduced into the carbon matrix (Figure 2), which is also supported by the C 1s and O 1s spectra (Figure S5, Supporting Information).…”

Critical Insight into the Relentless Progression Toward Graphene and Graphene‐Containing Materials for Lithium‐Ion Battery Anodes

“…N-and B-doped graphenes showed large reversible capacity (exceeding 1000 mAh g −1 ) and, most interestingly, an impressive rate capability with capacities of about 200 and 235 mAh g −1 at a massive current of 25 A g −1 , for N-and B-doped samples, respectively [ 57 ] (Table 1 ). Despite the promising results, the authors estimated power and energy density on a single electrode basis (in half-cell confi guration), hence, providing meaningless values.…”

“…In all these cases, however, only modest improvements (especially in terms of cycling stability) were observed with respect to the reports published few years before. Although several publications reported the active material mass loadings, [ 58,60,65,129,130,132,138,142,147,168,172,[177][178][179][180] as well as the tap density of the active material [ 57 ] and the density of the electrode, [ 63 ] no considerations about volumetric capacity were made. Some progression on composite anodes based on graphene and germanium (i.e., alloy material), MFe 2 O 4 (M = Co, Ni, Cu) and M x S y (M = Sn, Sb, In) were reported in 2012.…”

A Fe/Fe3O4/N-carbon composite with hierarchical porous structure and in situ formed N-doped graphene-like layers for high-performance lithium ion batteries

“…The low reversible capacity (∼260 mA h g −1 ) of the RHC matrix under the same conditions also confirms the validity of N doping and activated nanoparticle association by facile treatment. 16,18,33,34 Among these two factors, N-doping is the main because the capacity increase is ∼100 mA h g The microstructure variation of Fe/Fe 3 O 4 /N-carbon after 100 discharge-charge cycles was examined using TEM (Fig. S5 †).…”