Unexpected electrosorption capacity and selectivity of fungal hyphae derived carbon film for nitrate removal

Selective adsorption is of high value in many important areas, but this is a well-known challenge. Here, a self-supporting carbon film electrode, used as anode for selective adsorption of NO 3 – , was fabricated successfully by using fungus hyphae as feedstock. The removal of NO 3 – by the carbon film electrode is 0.345 m mol/g anode , accounting for 85.2 % of the total removed anions. The selectivity of NO 3 – over Cl - and NO 3 – over SO 4 2- is 6.7 and 13.8, respectively. The preferential electrosorption is relevant to the narrow micropores structure and the nitrogen doping of the carbon film, based on the pore size analysis and density functional calculation. This work opens a hopeful window in providing an effective approach to fabricate electrosorption materials and also could inspire the future development of selective materials for electrosorption of target ions.