Congratulations to Shao-Wei on his recent publication which investigated alkylated polyaniline redox polymers as highly-selective electrosorbents for the selective capture of nitrate from wastewater.
Published in Nature Communications, this work develops electrosorbents by tuning the hydrophobicity of redox polymers to preferentially bind the less-hydrated nitrate ion over chloride for selective electrochemical separation. By introducing tailored alkylation patterns onto a PANI backbone, the study achieves high nitrate uptake, strong nitrate-over-chloride selectivity, and excellent regeneration. A combination of electrosorption and AIMD simulations showed that alkylated PANIs exhibit strong binding affinity for nitrate via amine groups along with hydrophobic repulsion of chloride due to alkyl groups. This work highlights how controlling solvation in electroactive polymers can enhance nitrate selectivity and guide the design of next-generation redox-mediated separations