Design of multifunctional 1D/2D polypyrrole nanotubes@pg-C3N4 binary nanocomposite for removal of mercury (Hg2+) from wastewater and supercapacitor applications

A multifunctional, highly efficient, 1D/2D Polypyrrole nanotubes@pg-C3N4 binary nanocomposite was prepared using a one-pot ultra-sonication approach. The influence of 1D and 2D nanomaterials on the behavior of developed PPy-NTs-based nanocomposite for eliminating Hg2+ ions was explored. The developed nanocomposite revealed greater adsorption performance to eliminate Hg2+ions from contaminated water. The PPy-NTs/pg-C3N4 potential as an excellent sorbent for the removal of Hg2+ and possible mechanisms were assessed using batch experiments involving multiple factors that can also optimize the maximum adsorption conditions that were found to be at pH = 5, 1 h stirring time, and 0.5 g/L adsorbent dosage. The maximum Hg2+ absorption capacity reached was 197 mg/g. The data were well fitted with the pseudo-second-order kinetic model, which indicates that the chemisorption process controls the Hg2+ ions adsorption onto the pg-C3N4/PPy-NTs. The four adsorption isotherms models were applied to analyze the adsorption of Hg2+ ions on the developed adsorbent. The data were well described with Freundlich isotherm, revealing the presence of heterogeneous adsorption sites. The effect of temperature and thermodynamic considerations were investigated, showing that Hg2+ ion adsorption is endothermic. Additionally, the prepared material was explored for the supercapacitor application. It delivered an outstanding electrochemical supercapacitor performance and remarkable cycling stability. (c) 2023 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.