Synthesis of SnO₂versus Sn crystals within N-doped porous carbon nanofibers via electrospinning towards high-performance lithium ion batteries

Abstract

The design of tin-based anode materials (SnO2 or Sn) has become a major concern for lithium ion batteries (LIBs) owing to their different inherent characteristics. Herein, particulate SnO2 or Sn crystals coupled with porous N-doped carbon nanofibers (denoted as SnO2/PCNFs and Sn/PCNFs, respectively) are fabricated via the electrospinning method. The electrochemical behaviors of both SnO2/PCNFs and Sn/PCNFs are systematically investigated as anodes for LIBs. When coupled with porous carbon nanofibers, both SnO2 nanoparticles and Sn micro/nanoparticles display superior cycling and rate performances. SnO2/PCNFs and Sn/PCNFs deliver discharge capacities of 998 and 710 mA h g(-1) after 140 cycles (at 100, 200, 500 and 1000 mA g(-1) each for 10 cycles and then 100 cycles at 100 mA g(-1)), respectively. However, the Sn/PCNF electrodes show better cycling stability at higher current densities, delivering higher discharge capacities of 700 and 550 mA h g(-1) than that of SnO2/PCNFs (685 and 424 mA h g(-1)) after 160 cycles at 200 and 500 mA g(-1), respectively. The different superior electrochemical performance is attributed to the introduction of porous N-doped carbon nanofibers and their self-constructed networks, which, on the one hand, greatly decrease the charge-transfer resistance due to the high conductivity of N-doped carbon fibers; on the other hand, the porous carbon nanofibers with numerous voids and flexible one-dimensional (1D) structures efficiently alleviate the volume changes of SnO2 and Sn during the Li-Sn alloying-dealloying processes. Moreover, the discussion of the electrochemical behaviors of SnO2vs. Sn would provide new insights into the design of tin-based anode materials for practical applications, and the current strategy demonstrates great potential in the rational design of metallic tin-based anode materials.

Metallic Sn‐Based Anode Materials: Application in High‐Performance Lithium‐Ion and Sodium‐Ion Batteries

“…Moreover, the intertwined 1D network structures can promote the charge‐transfer process and improve rate performance. Up to now, many 1D Sn‐based materials have been fabricated to be applied as anodes, such as 1D nanowires,19, 57, 59, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155 1D nanotubes,156, 157, 158, 159, 160 and 1D nanoarrays,5, 161, 162, 163, 164, 165, 166, 167 etc.…”

Pressure‐Induced Synthesis of Homogeneously Dispersed Sn/SnO2/C Nanocomposites as Advanced Anodes for Lithium‐Ion Batteries

“…As Sn/SnO 2 /C shows the best cyclability, its lithium storage performances were further tested. The CV curves show the cathodic peaks at 0.2–0.7 V and anodic peaks at 0.4–0.8 V, which correspond to the formation of Li−Sn alloy phases (Li 4.4 Sn, Li 3.5 Sn, LiSn, and Li 0.4 Sn) and extraction of Li from alloy phases, respectively (Figure a) . According to the first Coulombic efficiency (CE) of 79.9%, the first discharge and charge capacities are obtained as 941.0 and 752.2 mAh g −1 (Figure b), respectively.…”

“…According to the first Coulombic efficiency (CE) of 79.9%, the first discharge and charge capacities are obtained as 941.0 and 752.2 mAh g −1 (Figure b), respectively. The 20.1% irreversible capacity arises from formation of Li 2 O and the solid electrolyte interphase (SEI) layer . Figure c shows Nyquist plots, wherein the diameter of the semicircles represents the charge transfer resistance ( R ct ).…”

A Robust Hybrid of SnO2 Nanoparticles Sheathed by N‐Doped Carbon Derived from ZIF‐8 as Anodes for Li‐Ion Batteries

“…The high‐rate capacity and excellent reversibility of the electrode mainly originate from the specific NC matrices, which effectively alleviate the volume change and prevent the aggregation of SnO 2 particles, ensuring the outstanding rate performance. It is worth mentioning that the rate performance and reversibility of SnO 2 ‐NC polyhedrons are superior to the SnO 2 /N‐doped carbon nanofiber and other related N‐doped materials reported in the literature (Table S1, Supporting Information) . To gain further insights of the electrochemical performance, electrochemical impedance spectroscopy (EIS) measurements were conducted with a frequency range of 100 kHz to 10 mHz (Figure d and Figure S12, Supporting Information).…”