Fabrication of coal-based oxygen-rich porous carbon nanosheets for high-performance supercapacitors

Fig.1 SEM images of (a) MgAl-LDH, (b) PC-700, and (c, d) OPCN-700; (e, f) TEM images of OPCN-700 Fig.2 (a) XRD patterns of PC-700, PCN-600, OPCN-700, OPCN-800, and OPCN-900; (b) Raman spectra of PC-700, PCN-600, OPCN-700, OPCN-800, and OPCN-900; (c) N2 adsorption/desorption curves of PC-700, PCN-600, OPCN-700, OPCN-800, and OPCN-900; (d) Pore size distribution of PC-700, PCN-600, OPCN-700, OPCN-800, and OPCN-900; (e) XPS spectra of PC-700 and OPCN-700; (f) C1s and O 1s high-resolution spectra of OPCN-700Fig.3 (a) The O content of as-prepared PC-700, PCN-600, OPCN-700, OPCN-800, and OPCN-900 samples; Contact angle test of (b) PC-700; (c)OPCN-600; (d) OPCN-700; (e) OPCN-800; (f) OPCN-900 Fig.4 (a) CV curves of carbon samples at scanning rate of 10 mV s-1; (b) CV curves of OPCN-700; (c) GCD curves of OPCN-700; (d) The specific capacitances of carbon samples at different current density; (e) Nyquist plots of carbon samples; (f) Cyclic performance of OPCN-700Table 1 Pore structure parameters of PC-700, PCN-600, OPCN-700, OPCN-800, and OPCN-900