Faceted Antimony Particles with Interiors Reinforced with Reduced Graphene Oxide as High-Performance Anode Material for Sodium-Ion Batteries

Abstract

The attainment of "true reinforcement" in a composite and harnessing of the associated beneficial effects have been demonstrated here through the development of faceted crystalline Sb particles having the interiors reinforced with reduced graphene oxide (rGO). Such a unique and "near-ideal" micro/nanocomposite architecture has been achieved via a facile/cost-effective route by facilitating heterogeneous nucleation/growth of Sb-oxide particles on/ around dispersed rGO sheets upon incorporation of the same directly into the precursor suspension, followed by the reduction of Sb-oxide to Sb, in intimate contact with the rGO, during the subsequent single heat-treatment step. As a potential anode material for Na-ion batteries, the as-developed Sb/rGO composite exhibits a reversible Na-storage capacity of ∼550 mAh/g (@ 0.2 A/g) and a fairly high first cycle Coulombic efficiency (CE) of ∼79%, with the good reversibility being attributed to the coarse particle size of Sb and encompassing of rGO sheets inside the Sb particles. Furthermore, despite the coarse particle size, the Sb/rGO-based electrode exhibits outstanding cyclic stability, with negligible capacity fade up to 150 cycles (viz., ∼97% capacity retention), and rate capability, with >86% capacity being obtained upon raising the current density from 0.1 to 2 A/g, resulting in a capacity of ∼490 mAh/g, even at 2 A/g.

Facile and Scalable Development of High-Performance Carbon-Free Tin-Based Anodes for Sodium-Ion Batteries

“…After galvanostatic cycling (for 10 cycles), the resistance associated with the high-to-medium-frequency depressed semicircle (viz., R ct + R sei ) has been found to get significantly lowered for all of the Sn–Bi electrodes. This is presumably due to the removal of a native oxide layer (as was also reported earlier by us for other “alloying-reaction”-based electrodes) and improved wetting of the electrode-active particles with the electrolyte. , More importantly, the slopes obtained from the Warburg component’s lower-frequency region in the Nyquist plots (as in Figure S8) have been found to be relatively lower for the higher Bi-containing Sn–Bi electrodes (as presented in Figure b). Because the slope is inversely proportional to the diffusion coefficient, the EIS measurements corroborate the GITT results, reconfirming the increased overall Na-diffusivity with the Bi content.…”

Synthesis of Sb–pyromellitic acid metal–organic framework material and its sodium storage properties

“…The low initial efficiency mainly arises from the irreversible reduction of Sb 3+ to Sb 0 , and the irreversible consumption of SEI film formation. 42 As shown in Fig. 4(d), the coulombic efficiency increases to 98.6% after two cycles and remains relatively stable in the subsequent cycles.…”

Enabling intercalation‐type TiNb24O62 anode for sodium‐ and potassium‐ion batteries via a synergetic strategy of oxygen vacancy and carbon incorporation

“…Nevertheless, TNO x particles kept intact with rGO and no cracks were observed. rGO standing between clusters of particles might act as a reinforcement layer to provide structural stability to the electrode without losing the improvement in electronic conductivity 63 …”

“…rGO standing between clusters of particles might act as a reinforcement layer to provide structural stability to the electrode without losing the improvement in electronic conductivity. 63 To differentiate the capacity contribution of diffusionand surface-controlled processes in TNO and TNO x /rGO-32, CV curves at different scan rates were recorded in the potential range of 0.01 to 3 V (Figure S10). As the scan rate (ν) increases, the peak currents (i) of both TNO and TNO x /rGO-32 increase.…”