Fig. 3

a N2-sorption isotherms of Me-CFZ-900. b XRD patterns of CF-900, CFZ-900, and Me-CFZ-900. c Raman spectra of CF-900, CFZ-900, and Me-CFZ-900. d Bode spectra of CF-900, CFZ-900, and Me-CFZ-900 under a sine wave of 5.0 mV amplitude in the frequency range of 100 kHz to 10 MHz