## 3 Results
### Electrochemical Properties
In contrast, the specific discharge capacity of PVDF@Sb\({}_{2}\)O\({}_{3}\) and CMC@Sb\({}_{2}\)O\({}_{3}\) decreases to 286.3 and 272.3 mAh g\({}^{-1}\) after 200 cycles, respectively. The abnormal cycling performance and coulomb efficiency of PVDF@Sb\({}_{2}\)O\({}_{3}\) after 150 cycles may be caused by the collapse of the electrode structure with shedding of active materials. The excellent cycling stability of CMC-FA@Sb\({}_{2}\)O\({}_{3}\) electrode may be ascribed to that the cross-linking network could reinforce the electrode, as well as accommodate the volume change of the electrode in repeated lithiation and delithiation process. Figure 3: (**a–c**) Cyclic voltammetry curves of PVDF@Sb\({}_{2}\)O\({}_{3}\), CMC@Sb\({}_{2}\)O\({}_{3}\) and CMC-FA@Sb\({}_{2}\)O\({}_{3}\) at scan rate of 0.2 mV s\({}^{-1}\); (**d–f**) galvanostatic charge-discharge profiles of PVDF@Sb\({}_{2}\)O\({}_{3}\), CMC@Sb\({}_{2}\)O\({}_{3}\) and CMC-FA@Sb\({}_{2}\)O\({}_{3}\) in the initial five cycles at 0.2 A g\({}^{-1}\). Figure 4b shows the rate capabilities of PVDF@Sb\({}_{2}\)O\({}_{3}\), CMC@Sb\({}_{2}\)O\({}_{3}\) and CMC-FA@Sb\({}_{2}\)O\({}_{3}\) at current density ranging from 0.05 to 0.5 A g\({}^{-1}\). At a current density of 50 and 100 mA g\({}^{-1}\), capacity of CMC-FA@Sb\({}_{2}\)O\({}_{3}\) is lower than PVDF@Sb\({}_{2}\)O\({}_{3}\) and CMC@Sb\({}_{2}\)O\({}_{3}\) under low current density. This may be due to the slow activation of electrodes under the effect of aggregated Sb\({}_{2}\)O\({}_{3}\) and CMC-FA binder. PVDF@Sb\({}_{2}\)O\({}_{3}\) and CMC@Sb\({}_{2}\)O\({}_{3}\) have same downward trends even though they have higher specific discharge capacity than CMC-FA@Sb\({}_{2}\)O\({}_{3}\), whose specific discharge capacity is relatively stable. When current density was increased to 0.2, 0.3 and 0.5 A g\({}^{-1}\), the reversible capacities of CMC-FA@Sb\({}_{2}\)O\({}_{3}\) were 382.9, 344.3 and 295.4 mAh g\({}^{-1}\), respectively, which is better than PVDF@Sb\({}_{2}\)O\({}_{3}\) and CMC@Sb\({}_{2}\)O\({}_{3}\). Moreover, when the current density returns to the initial, the capacity of CMC-FA@Sb\({}_{2}\)O\({}_{3}\) could recover to ~569 mAh g\({}^{-1}\), implying the good rate capability. The EIS measurements were conducted to test the electrochemical kinetics of different kinds of electrodes, and the test frequencies ranged from 0.1 to 100 kHz. Figure 4c,d show the Nyquist plots of three kinds of electrodes in initial states and after 200 cycles at 0.2 A g\({}^{-1}\), respectively. The equivalent circuit (inset in Figure 4c,d) was obtained using Nova software. For the impedance spectra before the discharge as shown in Figure 4c, the semicircles in the high-frequency region correspond to charge-transfer resistance (R\({}_{\rm ct}\)) in the interface of electrodes and electrolyte, and the inclined lines in the low frequency region are attributed to insertion of lithium-ions into the negative electrode [48]. R\({}_{\rm e}\) was the internal resistance of the as-assembled cell, CPE\({}_{\rm i}\) represents constant phase element of the electrode/electrolyte interface, and Z\({}_{\rm w}\) represents the Warburg impedance. The R\({}_{\rm ct}\) of the initial CMC-FA@Sb\({}_{2}\)O\({}_{3}\) electrode is ~269 \(\Omega\), and the PVDF@Sb\({}_{2}\)O\({}_{3}\) and CMC@Sb\({}_{2}\)O\({}_{3}\) are about 733 and 593 \(\Omega\), respectively, much larger than the CMC-FA@Sb\({}_{2}\)O\({}_{3}\). It can be seen in Figure 4d that in the impedance spectra after 200 cycles, the semicircle in the high frequency region corresponds to the resistance of SEI film, and the semicircle at middle frequency correspond to R\({}_{\rm ct}\), the inclined line at low frequency reflections are attributed to insertion of lithium-ions into the negative electrode [49].