The conversion reaction mechanism of bimetallic Ni–Fe hydroxycarbonate and its encapsulation in carbon nanospheres for achieving excellent Li-ion storage performance

Abstract

The search for promising anode materials with optimum compositions for use in lithium ion batteries (LIBs) is still underway.

Novel synthesis method of cobalt hydroxycarbonate hydrate‐reduced graphene oxide composite microspheres for lithium‐ion battery anode

“…The peaks at 1631, 1452, 1401, and 1114 cm À1 are matched with the C=O stretching, CO 3 stretching, C-O stretching vibration, and CO 3 in-plane scissoring, respectively. 1,30,31 Another peak at 3500 cm À1 consistent with the O-H stretching vibration and the peak at 751 cm À1 corresponded to the C-C stretching vibration. 32,33 The Raman spectrum of CoHC-rGO in Figure 2B exhibits two peaks at 1348 and 1599 cm À1 , which correspond to the D and G bands of rGO, respectively.…”

“…2,35 The O 1s spectrum (Figure 2E) displays several peaks of OH À (530.4 eV), CO 3 2À (531.0 eV), and H 2 O (532.5 eV). 1,33 The C 1s spectrum in Figure 2F exhibits peaks at 285.5, 287.9, and 289.0, consonant with C-C, C-O, and CO 3 2À , respectively. 33,36 The overall fitted spectra of CoHC-rGO indicate the formation of a Co 2 CO 3 (OH) 2 -0.22H 2 O phase.…”

“…Diverse compositions of anode materials have been explored for lithium-ion batteries (LIBs). [1][2][3][4][5][6] Transition metal compounds (TMCs) with multiple anions convert into individual TMCs during the first cycle. This makes TMCs with multiple anions exhibit superior electrochemical properties compared to single-component TMCs.…”

“…10,[15][16][17][18][19][20] Park et al synthesized hollow carbon nanospheres embedded in nickel-iron hydroxyl carbonate (NiFeHC) nanocrystals and achieved reversible discharge capacities of 593 mA h g À1 up to 700 cycles. 1 Lim et al developed cobalt hydroxy sulfide embedded within the shells of hollow carbon nanospheres. 2 The carbon shell and synergetic effect of nanocomposite formation from the doubleanion TMC contributed to superior cycle and rate performance of the cobalt hydroxy sulfide anode material.…”

“…The synthesis process also affected the electrochemical properties of the TMCs due to the formation of different morphologies and sizes. 1,5,16,[21][22][23] Multiple anions TMCs have mainly been synthesized using a liquid solution process. [24][25][26] Spray pyrolysis is suitable for the production of microspheres composited with carbonaceous materials and has been successfully applied to the synthesis of nanostructured TMCs.…”