Cellulose derivatives crosslinked by citric acid on electrode surface as a heavy metal absorption/sensing matrix

Modification of cellulose derivatives with citric acid leads to gain in sorption capacity towards metal ions, which has been many times applied for heavy sequestration. This work, the first time, investigated in-situ coating a carbon electrode acid-crosslinked derivatives. The occurrence crosslinking bonds was revealed using infrared spectroscopy and thermogravimetric analysis, while other features were electrochemical methods. Electrodes modified by casting aqueous solutions (hydroxyethyl cellulose, HEC thermally pre-treated carboxymethyl T-CMC) mixed (CA) on surface, followed thermal treatment (110 °C, 1 h) reach requested HEC-CA T-CMC-CA hydrogels coated glassy electrodes. After absorption cations from solution, electrodes both exhibited stripping voltammetry peaks Pb, Cd Cu, contrary prepared without crosslinking. It also observed that surface change its impedance reversibly after deposition acid-induced removal Pb2+. Assessment Pb2+ sensing properties detection limit 0.39 mg L−1 sensitivity 9.91 μA L mg−1. Therefore, can be employed preparation cheap sustainable sensors similar surfaces.