A Venus-flytrap-inspired pH-responsive porous membrane with internal crosslinking networks

摘要: A Venus-flytrap-inspired pH-responsive polybenzimidazole (PBI) porous membrane is designed and fabricated for flow battery application. In the design, PBI membranes with tunable pores are firstly created by introducing hydrophilic sulfonated poly(ether ether ketone) (SPEEK) into casting solution. Then internal crosslinking networks built on pore walls in situ acid–base reaction between SPEEK to improve selectivity, while keeping high conductivity. The process closely resembles trapping mechanism of Venus flytrap plant, whose lobes close when they sense contact an external force. Moreover, a vanadium (VFB) resultant exhibits outstanding performance coulombic efficiency 99.5% energy 89.1% at current density 80 mA cm−2, which much higher than commercial Nafion 115 (93.4%, 82.5%). Most importantly, VFB prepared keeps stable after continuously running more 10 000 cycles 140 showing super-high stability. This work provides simple biomimetic strategy fabricate conductivity