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Page 4 of 12 Zhang et al. Energy Mater 2024;4:400043 https://dx.doi.org/10.20517/energymater.2023.102

Figure 1. (A) Preparation strategy of SiO /G/C composite; (B) TEM image and (C) SEM image of SiO /G/C; (D) TEM photo and (E)
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SEM photo of SiO /G composite; (F) TEM image and (G) SEM imageof SiO /C composite. CNT: Carbon nanotube; TEM: transmission
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electron microscopy; SEM: scanning electron microscopy.
carbon. Energy dispersive X-ray spectroscopy mapping shown in Supplementary Figure 1 reveals the
uniformity of the SiO /G/C composite. This close contact between SiO and the dual-carbon network
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buffers volume changes during cycling and enhances electron transport pathways for the SiO /G/C.
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HRTEM images of SiO /G/C in Supplementary Figure 2A confirm the crystalline structure of CNTs and
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graphite [Supplementary Figure 2B] and the amorphous structure of SiO [Supplementary Figure 2C].
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Furthermore, SiO particle sizes, determined to be less than 500 nm, confirm the efficiency of the ball
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milling method. The lattice fringes of graphite in SiO /G/C, corresponding to (002) planes, were calculated
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to be approximately 0.33 nm. However, the TEM image of SiO /G [Figure 1D] illustrates inadequate
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attachment of SiO particles to graphite sheets, even after sonication, indicating the potential for CNTs to
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assist in exfoliating graphite. Additionally, SEM images of SiO /G [Figure 1E] confirm that graphite alone is
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insufficient for rapidly forming a carbon network and embedding SiO . The TEM [Figure 1F] and SEM
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images [Figure 1G] of the SiO /C composite demonstrate efficacy of CNTs in preventing SiO nanoparticle
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aggregation. However, owing to their 1D morphology, SiO particles in the SiO /C composite are more
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exposed than those in the SiO /G/C sample. From the abovementioned results, creating a robust framework
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to stabilize SiO with just one type of carbon material is challenging. However, leveraging the advantages of
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3D graphite and 1D CNTs makes uniform dispersion of SiO within a dual-carbon network achievable. This
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approach ensures structural stability and prevents electrical contact loss during cycling.
To examine the structure and components of the SiO /G/C, SiO /G, and SiO /C composites, different
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techniques, including XRD, Raman, FTIR spectroscopy, and XPS, were employed. XRD analysis [Figure 2A]
elucidated the structural characteristics of the three composites mentioned earlier. Peaks observed at 26.6°,
44.6°, 54.7°, and 77.5° were identified as the diffraction planes of (002), (101), (004), and (110) for graphite
[22]
(JCPDS no. 04-0836) , respectively. The characteristic graphite peak at 26.6° observed in SiO /G also
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appeared in SiO /G/C. Peaks at 26.4° and 44.7° (SiO /C) relatively weaker than graphite in SiO /G/C and
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SiO /G composites corresponded to the (003) and (101) diffraction planes, indicating the presence of
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