pH-responsive hierarchically porous self-assembly bioinspired Al2O3 ceramic membranes

In this work, we present a preparation strategy for pH-responsive hierarchically porous bioinspired Al2O3 ceramic membrane (pH-HPBA-CM). The pore size of the pH-HPBA-CM could be adjusted by altering the pH value. With the increase of the pH value, the porosity gradually decreases and the compressive strength of the pH-HPBA-CM is also affected by the pH value, which presents an increasing trend with the increase of the pH value. The variation of compressive stress versus displacement of the pH-HPBA-CMs (stress-strain relationship) prepared at different pH values was discussed. A mechanical simulation experiment was carried out to better analyze the reason why the honeycomb-like structure of the pH-HPBA-CM has excellent specific strength. In the simulation process, the small pore model (15 mu m) can be regarded as part of the large pore model (35 mu m). The simulation of the total deformation, equivalent stress, and equivalent elastic strain were obtained by setting the load pressure of 100 MPa. At this load pressure, the maximum deformation of the entire ceramic membrane is far lower than the theoretical limit value of its simulation, and all of them are distributed at the junction (connectional pores). This work provides a new insight into the effective preparation of pH-responsive hierar-chically porous bioinspired ceramic membranes with high porosity, excellent mechanical performance, and tunable pore size.