## 3 Results and Discussion  
The carbon phase in SiOC significantly influences their properties as matrices for alloying nanoparticles [11] as well as their electrochemical performance. As we described in our recent work [35], not only is the amount of carbon important but also its structure. We showed that the incorporation of the ordered carbon phase in the form of small graphitic flakes in the SiOC structure is beneficial for electrochemical activity towards lithium ions and cycling stability. A thorough analysis of SiOC/Sn and SiOC/C/Sn composites by means of Raman spectroscopy helps to correlate the carbon structure with the composites' properties. The Raman spectra of all investigated materials (Figure 1a) exhibited D and G modes at \(\sim\)1340 cm\({}^{-1}\) and \(\sim\)1580 cm\({}^{-1}\), respectively, characteristic of carbonaceous materials. For further analysis, these modes were deconvoluted into five peaks [42], as presented in Figure 1b-f, Figure S1, and Table S1 and Table S2 (in the Supplementary Materials). Pure SiOC exhibits a typical response with a strong D1 peak (\(I_{\text{D1}}\) = 0.950), related to the disordered forms of carbon, and about half-size G and D2 peak intensities (\(I_{G}\) = 0.441 and \(I_{D2}\) = 0.379), corresponding to the ideal and damaged graphitic lattice, respectively [42; 43]. The addition of the tin precursor to SiOC (SiOC/Sn-40% sample) led to minor changes in the carbon structure compared to pure SiOC--slightly less intense D1 and D2 bands. On the other hand, replacing part of the ceramic with graphite (in the case of ternary SiOC/C/Sn composites) caused a significant rise in the G band intensity, which is an expected effect for the introduction of ordered carbon networks in the material. An interesting effect is noted when one compares samples with the same amount of graphite but of different tin content. The SiOC:C\({}_{0.2}\)/Sn-60% sample exhibits a lower \(I_{\text{D1}}\)/\(I_{\text{G}}\) ratio than the SiOC:C\({}_{0.2}\)/Sn-40% sample (0.481 vs. 0.551, respectively), suggesting a higher fraction of ordered carbon in sample SiOC:C\({}_{0.2}\)/Sn-40%. This indicates that tin oxide consumes mainly the disordered free carbon phase during the carbothermal reduction process. The structure was further investigated by means of XRD analysis (Figure 2). Pure SiC (Figure 2 black curve) displayed only a noisy signal with a halo at \(\sim\)22\({}^{0}\), which is typical for these types of amorphous materials [44]. All ternary composites exhibited a series of sharp peaks coming from graphite and tin. The peaks at 26.2\({}^{\circ}\) and 55\({}^{\circ}\) confirm the presence of a hexagonal structure of graphite within the composite materials. Other graphitic peaks are missing, probably because of hindrance by the ceramic phase. The remaining peaks of ternary composites correspond to \(\beta\)-tin (the PDF card Sn-ref_00-004-0673 is presented in Table S4 in Supplementary Materials). No signals related to SnO\({}_{2}\) were observed, suggesting complete carbothermal reduction of SnO\({}_{2}\) during pyrolysis. The relative intensities between graphitic and \(\beta\)-Sn depend on the composition, with the graphitic peak more pronounced for the graphite-rich SiO:C\({}_{0.2}\)/Sn-40% sample and the \(\beta\)-Sn peaks the most intense for the SiC:C\({}_{0.1}\)/Sn-60% material. Figure 1: (a) Raman spectra of SiC, graphite and composite materials after background subtraction with custom settings, fitting results for (**b**) pure SiOC, (**c**) SiOC/Sn-40%, (**d**) SiOC:C\({}_{0.1}\)/Sn-60%, (**e**) SiOC:C\({}_{0.2}\)/Sn-60%, and (**f**) SiOC:C\({}_{0.2}\)/Sn-40%. The investigations of morphology, structure, and composition were conducted using SEM-EDX techniques. Figure 3a,b show the morphology of SiOC and SiOC:C\({}_{0,2}\)/Sn-40%, respectively. The pure SiOC powder consisted exclusively of slate rock-like particles of various sizes and shapes.