Wood-Derived Carbon with Selectively Introduced C═O Groups toward Stable and High Capacity Anodes for Sodium Storage

Abstract

Biomass-derived carbon is a promising sustainable anode material for sodium-ion batteries (SIBs). Although the electrochemical performance can be improved by introducing functional groups, the selective introduction of single functional groups into biomass carbon remains difficult. Here, we overcome this challenge by developing a wood-derived carbon with selectively introduced CO groups by combining tetramethoxysilane (TMOS) with wood cellulose pulps. The integration of TMOS introduces abundant CO groups into the carbon during the polycondensation and pyrolysis process. The CO groups play a dominant role in anode surface-controlled processes, and this leads to improvements in pseudo-capacity and fast electrode process kinetics. Besides, the introduction of CO groups generates oxygen functional active sites that promote Na + adsorption and creates a sufficiently large graphene interlayer distance. The as-obtained carbon shows a high capacity of 330 mAh g −1 at 40 mA g −1 and excellent cycling stability. Moreover, our strategy is simple and uses wood cellulose pulps as precursors. It therefore enables lowcost and large-scale synthesis of carbon anode materials for SIBs.

Carboxyl‐Dominant Oxygen Rich Carbon for Improved Sodium Ion Storage: Synergistic Enhancement of Adsorption and Intercalation Mechanisms

“…C1600-M can deliver a large discharge capacity of 382 mAh g −1 at a low current density of 30 mA g −1 ; even at a high current density of 2 A g −1 , a specific capacity of 152 mAh g −1 can still be sustained, indicating the superior rate capacities that are also comparable to many reported advanced carbon-based SIBs anodes. [21,25,32,37,[54][55][56][57][58][59] When the current density recovers to 0.1 A g −1 , the capacity restores to 255.3 mAh g −1 , suggesting an excellent electrochemical stability of C1600-M. By contrast, both C1600 and C1600-M-R show much inferior capacities to C1600-M within all the tested current densities, implying the significant enhancement effects of carboxyl groups on reversible Na + storage. Figure 3e gives the long-term cycling stabilities of the three anodes at the current density of 1.5 A g −1 from which C1600-M anode can maintain a high reversible capacity of 141 mA h g −1 (80.2% retention) after 2000 cycles with the Coulombic efficiency keeping around 100%, demonstrating the excellent stability of oxygen-containing groups during long-term cycling.…”

In Situ Nitrogen Retention of Carbon Anode for Enhancing the Electrochemical Performance for Sodium‐Ion Battery

“…All the samples were mainly composed of C, and contained around 20 % of O and N in total. O came from the stabilisation in air atmosphere, which provided bridges for crosslinking reactions and eventually formed into functional active sites to promote Na + adsorption [20] . The ratio of O/C of PAZ‐CF‐1100 was the lowest.…”

“…O came from the stabilisation in air atmosphere, which provided bridges for crosslinking reactions and eventually formed into functional active sites to promote Na + adsorption. [20] The ratio of O/C of PAZ-CF-1100 was the lowest. N was from the polymer chains, and PANIA originally had 11.15 % of N (Figure S6).…”

Stable fast‐charging electrodes derived from hierarchical porous carbon for lithium‐ion batteries

“…During the cathodic scan at the first cycle of CV, small reduction peaks were detected at 0.85 V in AC, which indicate a reaction between Li-ions and functional groups on the carbons. [21][22][23] In addition, the broad peaks detected in the range between 0.4 and 0.8 V, during the cathodic process, corresponded to decomposition and formation of a solid electrolyte interphase (SEI) film on the carbon surface. 21 However, those peaks disappeared at the third cycles, as shown in Figure 2A, due to the stabilization of SEI layer.…”

“…[21][22][23] In addition, the broad peaks detected in the range between 0.4 and 0.8 V, during the cathodic process, corresponded to decomposition and formation of a solid electrolyte interphase (SEI) film on the carbon surface. 21 However, those peaks disappeared at the third cycles, as shown in Figure 2A, due to the stabilization of SEI layer. The SEI layer significantly affects the first cycle of the CV and the Coulombic efficiency.…”