Array of nanosheets render ultrafast and high-capacity Na-ion storage by tunable pseudocapacitance

Abstract

Sodium-ion batteries are a potentially low-cost and safe alternative to the prevailing lithium-ion battery technology. However, it is a great challenge to achieve fast charging and high power density for most sodium-ion electrodes because of the sluggish sodiation kinetics. Here we demonstrate a high-capacity and high-rate sodium-ion anode based on ultrathin layered tin(II) sulfide nanostructures, in which a maximized extrinsic pseudocapacitance contribution is identified and verified by kinetics analysis. The graphene foam supported tin(II) sulfide nanoarray anode delivers a high reversible capacity of ∼1,100 mAh g−1 at 30 mA g−1 and ∼420 mAh g−1 at 30 A g−1, which even outperforms its lithium-ion storage performance. The surface-dominated redox reaction rendered by our tailored ultrathin tin(II) sulfide nanostructures may also work in other layered materials for high-performance sodium-ion storage.

Encapsulation of CoSx Nanocrystals into N/S Co‐Doped Honeycomb‐Like 3D Porous Carbon for High‐Performance Lithium Storage

“…According to Equation (3), by plotting I ( V )/ v 1/2 versus v 1/2 at different potentials, one can calculate the values of k 1 (slope) and k 2 (intercept) from the straight lines. We can distinguish the fraction of the current from surface capacitance and Li + semiinfinite linear diffusion 62. As a result, 67% of the total capacity is identified as the capacitive contribution at the scan rate of 1 mV s −1 (Figure 6c).…”

Holey 2D Nanomaterials for Electrochemical Energy Storage

“…Chao et al fabricated the flexible graphene foam (GF)-supported SnS electrodes by a rapid one-step in situ hot bath route. [62] The as-synthesized GF-supported SnS showed an average lateral size of 50-70 nm and thickness of ≈5 nm. Interestingly, these thin SnS nanosheets contained numerous tiny nanoclusters (≈5 nm) and nanocavities (3-5 nm), and formed the hierarchical porous structure within the composites.…”

Vertically Aligned Graphene Nanosheet Arrays: Synthesis, Properties and Applications in Electrochemical Energy Conversion and Storage

“…Thus far, these lowdensity GFs have demonstrated decent performance in electricdouble-layer capacitors (EDLCs). [13,18] In addition, doping [19] and compositing 3D GFs with other active materials (e.g., CNTs, [20] polymer, [21] Si, [22] metal, [23] metal oxides, [24] metal sulfides, [25] ) further extend their applications to fields such as lithium-ion batteries (LIBs), pseudocapacitors, and electrocatalysts. [8,14,15] Recently, another type of 3D graphene, i.e., VAGNAs, has attracted increasing interest for its application as electrochemical electrodes due to its superior reaction kinetics and mass transportation capability to that of GFs.…”