Eco-friendly alginate-doped cotton pad as a separator for zinc-ion batteries

In this study, we successfully prepared an alginate-doped cotton pad biocomposite by a facile one-step dip-coating method. Herein, zinc acetate was used as the green electrolyte. The structure, ionic conductivity, and cycle performance of the prepared composites were estimated. The composite here showed favorable fibrous structure. Furthermore, the introduction of alginate into the cotton pad improved its surface hydrophilicity, electrolyte uptake ability, and mechanical stiffness. Tensile strength and elongation at break were found to be 11-13 MPa and 49-54%, respectively. Young's modulus was in the range of 214-287 MPa. The alginate-doped cotton pad also showed substantial ionic conductivity ranging from 0.91 to 1.96 mS/cm. This composite offered a balance between excellent mechanical properties, electrochemical stability, and ion flow. Additionally, the preliminary electrochemical studies showed that the half zinc-ion battery assembled with the alginate-doped cotton pad separator was stable throughout 200 h of cycling. This work implemented the versatility of cotton and alginate as a biocomposite in energy storage application. Cotton matrix, alginate and electrolyte are entirely green component which is not a threat to the environment. The findings established the employment of the simple and low-cost yet effective of cotton and alginate as an alternative separator material for zinc-ion batteries.

Automated summary

In this study, an alginate-doped cotton pad biocomposite was prepared using a dip-coating method. The composite showed a favorable fibrous structure, improved hydrophilicity, and enhanced mechanical stiffness due to the introduction of alginate. The composite also exhibited substantial ionic conductivity and stability in zinc-ion battery cycling.