Fig. 3: Enhanced stability and conductivity of ZIF-8-GO nano-sandwiches.
From: Sandwiching of MOF nanoparticles between graphene oxide nanosheets among ice grains
a, b Powder X-ray diffraction experiments and N2 adsorption isotherm showed the stability of ZIF-8-GO nano-sandwiches after exposure to dilute hydrochloric acid (pH = 2) and boiling water. c Energy profiles associated with a linker vacancy formation reaction in bulk (black dashed line) and on (100) crystal surface (blue dashed line) between ZIF-8 with HCl/H2O. The reaction consists of two steps. In the first step (labeled I), a HCl molecule is adsorbed onto Zn cations and then breaks a Zn-N bond by donating a proton to the N of the ligand to form a dangling linker. In the subsequent step (labeled II), a water molecule attaches to Zn and attacks a second Zn-N bond to generate a protonated organic ligand. Molecular (atomic) densities of ZIF-8 (black line), water (blue line), GO (purple line), Cl- (green line), and H3O+ (red line) obtained from the MD simulation of ZIF-8 in solution without (d) and with (e) a GO nanosheet. Snapshots of the simulated system at t = 300 ns from MD simulation of ZIF-8 in solution without (f) and with (g) the GO nanosheet. h Optical image and inserted schematic of the two-electrode device. i Conductivity of ZIF-8-GO with different oxidation degrees. Each conductivity was averaged from 50 independent experiments. Error bars are the standard errors of the mean. j Conductivity of ZIF-8-GO nano-sandwiches after harsh treatment (pH = 2). Each conductivity was averaged from 50 independent experiments. Error bars are the standard errors of the mean. Source data are provided as a Source Data file.
