## 3 Results and Discussion  
### Physical Properties and Surface Characteristics of CP and CDPC  
The thermal analysis results of the CP sample are depicted in Figure 2. As shown in Figure 2, the differential thermal analysis (DTA) curve exhibits two distinct exothermic peaks at temperatures of 318 \({}^{\circ}\)C and 597 \({}^{\circ}\)C. Simultaneously, the thermogravimetric (TG) analysis curve displays two stages of mass loss. The initial stage, occurring within the temperature range of roughly 500-650 \({}^{\circ}\)C and accounting for an 82.16% reduction in mass, is attributed to the combustion of constituents contained within the CP. Beyond 800 \({}^{\circ}\)C, the sample's mass demonstrates a state of relative stability. It can be inferred that at this stage, the remaining components of coal oxide of low temperature at 800 \({}^{\circ}\)C are potentially intermixed with trace amounts of metal oxides found in the coal. In Figure 3a,b, SEM images of CP and CDPC illustrate distinct surface morphologies between the two materials. Specifically, the CP material consists of particles with an average size of approximately 20-20 \(\upmu\)m, while CDPC exhibits a structure characterized by small, porous pieces with a variety of mesopores and macropores. Figure 2: Thermogravimetric (TG—black) and differential thermal analysis (DTA—red) of CP. From SEM images (Figure 3a,b), it can be observed that after oxidation, a rough surface with wrinkles and folds is formed, which was the result of deformation upon the exfoliation and restacking processes. These changes in morphology can be due to sp3 carbons and various GO structural defects like the formation of oxygen-containing functional groups in the basal planes [17]. The existence of macropores and mesopores will not only assist electrolytes in penetrating the materials in full depth but also shorten the ion diffusion paths effectively. The micropores could further provide more active sites for the insertion of lithium ions [30]. Figure 3f is a TEM image of CDPC, displaying a richer porous structure and more even pore size distribution. The sheet-like structure of graphene at a higher resolution, as shown in Figure 3g, reveals that the porous carbon material has sizes ranging from 3 to 10 nm. The well-developed pore distribution, presence of numerous  
Figure 3: (**a,b**) SEM images of CP and CDPC; (**c**) EDX spectrum of CDPC; (**d**) XRD pattern of CP (black) and CDPC (red); (**e**) Raman spectra of CP (black) and CDPC (red); (**f**) TEM of CDPC with low resolution and (**g**) with high resolution. active sites, and appropriate migration channels for ions enhance the electrochemical parameters necessary for the fabrication of supercapacitors, batteries, and electrochemical sensors [6; 12; 18; 19]. The EDX analysis results (presented in Figure 3c and Table 1) reveal that the primary constituents of the CDPC material are carbon with a content of 80.88% by weight, alongside trace amounts of various impurities, including oxygen, aluminum, silicon, sulfur, and manganese (Mn). The XRD analysis presented in Figure 3d reveals distinct diffraction peaks for CP occurring at scattering angles between 20 and 30 degrees and weaker diffraction peaks between 41 and 45 degrees, corresponding to the (002) and (100) planes of disordered carbon. The narrower and sharper diffraction peaks of (002) and (100) signify a more ordered crystal structure of the carbon sample, with a higher degree of graphitization [31]. The CDPC phase composition is mainly graphite, along with phases of MnO, MnO\({}_{2}\), and MnS. The obtained result is consistent with the above EDX analysis results. Figure 3e shows the G-band of 1592 cm\({}^{-1}\), which represents a shift to a larger wavenumber than that of graphite (1570 cm\({}^{-1}\)) due to graphite oxidation. The D-band (1349 cm\({}^{-1}\)) characterizes defect formation and distortion due to the presence of in-plane heteroatoms, grain boundaries, and aliphatic chains.