Page 115 - Read Online

Page 46 of 64 Rehman et al. Energy Mater 2024;4:400068 https://dx.doi.org/10.20517/energymater.2024.06

Figure 20. (A) (a) XRD pattern of BTO@SnO @P-C and SnO @P-C, (b) SEM image, (c) TEM with SAED pattern image (inset), and (d)
2 2
-1
-1
HR-TEM image. (B) Long cycle performance of BTO@SnO @P-C at (a) 2 A g and (b) 10 A g . (C) In-situ XRD analysis of
2
-1
BTO@SnO @P-C at the initial cycle: (a) Voltage-time curves at 0.1 A g (left) and BTO (1 1 0) plane contour pattern (right), (b) XRD
2
profile of BTO (1 1 0) when discharged from 1.5 to 0.1 V, and (c) Corresponding voltage-2θ curves, (d) XRD profile of BTO (1 1 0)
[206]
charged from 0.1 to 1.5 V, and (e) Corresponding voltage-2θ curves. Reproduced with permission from . Copyright © 2022 Elsevier.
provided the built-in electric field effect generated by the BTO layer due to ferroelectric polarization, further
augmented by the piezoelectric effect that could increase due to volume expansion during alloying of SnO
2
in the core-shell structure. These synchronous effects highly improved the performance as an SIB anode
with an awe-inspiring reversible capacity of 144.4 mAh g over 10,000 cycles at 10 A g with extra fast
-1
-1
charging (99% charged in 1 min), as shown in Figure 20B. Detailed in-situ XRD studies [Figure 20C] proved
that the BTO (110) plane showed evident peak shifts during (dis)charging and participated in the stability of
the anode.
A rGO composite of Sn/Sb as an SIB anode delivered a capacity of 320 mAh g over 300 cycles at
-1
-1
500 mAh g . However, upon continued cycling 600 times, the capacity continuously faded to
175 mAh g -1[275] . Multiple reports have realized that the potential of Sb SnO (SSO) can be at par with other
5
2
-1
commercial anodes because of its high theoretical capacity of 1,195 mAh g . Main issues that need to be
addressed are its slow ion transfer kinetics and poor electronic conductivity. Chen et al. have recently
[276]
developed an electrospun PCNF matrix embedding SSO nanoparticles along with a Sn/Sb array . The
hybrid can cope with the above issues. In addition, it can inhibit side reactions, offer volume buffering, and
+
expand grain boundaries with more active sites for Na storage. The material showed a capacity retention of
-1
-1
-1
440 mAh g over 450 cycles at 0.5 C while sustaining a rate capability of 281.8 mAh g at 500 mA g . In
another recent report, Sn and Sb oxides composited within porous carbon wires showed decent Na storage
+
-1
capacity as an anode. The SSO-based composite delivered a sustaining capacity of 448 mAh g at 50 mA g
-1
after 150 cycles . At a high current density of 3 A g , the composited SSO anode showed a capacity of
[277]
-1
-1
427 mAh g after 200 cycles. The performance was attributed to the hybrid structural design in which the
porous C wires encompassed the metallic Sn, Sb, and the oxide SSO state that could excellently bear the
volumetric stress. The unique morphology provides abundant diffusion pathways in the form of channel-
like arrays that make ionic diffusion faster. It also bears a high number of active sites that, along with well-
distributed metallic and oxide domains, can enhance the conductivity and improve the kinetics of the
charge transfer process.