ZIF-8/Chitosan Composite Hydrogel as a High-Performance Separator for Bioelectrochemical Systems

Chitosan biopolymer membranes reinforced with channel-selective ZIF-8 nanofillers were developed and characterized for use as separators in bioelectrochemical systems. The study focused on the application of biopolymer chitosan in combination with ZIF-8 as nano reinforcement agents to improve membrane performance. Key properties such as water retention, chemical and thermal stability, surface resistance, antifouling ability, and ionic conductivity of the mixed matrix membranes (Composite ZIF-8/chitosan) were evaluated and compared with commercial Nafion-117 and nanofiltration (NF) membranes. The composite ZIF-8/chitosan membranes exhibited excellent water retention and structural stability under harsh conditions, while reducing surface resistance and effectively rejecting organic contaminants and salts (NaCl, Na₂SO₄). Impressively, the ionic conductivity reached 0.105 S/cm, which is similar to that of Nafion-117. These results suggest that biopolymer chitosan reinforced with ZIF-8 nanofillers offers a sustainable and cost-effective alternative for use as separators in bioelectrochemical systems applications.