Tunable isoporous ceramic membranes towards precise sieving of nanoparticles and proteins

Abstract

Ceramic membranes have attracted widespread attention in industrial applications due to their excellent performance such as high flux, excellent stability and long lifetime. However, it is still a great challenge to prepare high-performance ceramic membranes with uniform pore size and high porosity using the existing manufacturing process. To this end, we have prepared hierarchical isoporous alumina ceramic membranes (IAMs) aided by the self-assembly of polystyrene-b-polyethylene oxide (PS-b-PEO) block copolymer in a sol-gel system. The packing and coalescence of spherical micelles self-assembled by PS-b-PEO and aluminum oligomers promote the formation of Allihn condenser-like channels in the isoporous separation layer (ISL). Control over the pore structure of ISL is achieved by tailoring the PS segment of PS-b-PEO, leading to the pore window rise from 8.3 to 19.7 nm. The pure water permeability of the corresponding IAMs increases from 151.6 to 223.2 L m−2 h−1 bar−1. The selective separation performance of IAMs is evaluated using gold nanoparticles (5–37 nm) and proteins (lysozyme, ovalbumin, bovine albumin serum and human immunoglobulin). The practicability, tunability and versatility of the strategy provided in this work pave the way for high-performance isoporous ceramic membranes fabrication.