Layer-by-Layer Assembly of Polyelectrolytes on Urchin-like MnO2 for Extraction of Zn2+, Cu2+ and Pb2+ from Alkaline Solutions

Abstract

Three-dimensional (3D) urchin-like MnO2@poly (sodium 4-styrene sulfonate) (PSS)/poly (diallyl dimethylammonium chloride) (PDDA)/PSS particles were prepared via the layer-by-layer (LBL) assembly of polyelectrolytes for the extraction of Zn2+ from alkaline media. The adsorption performance of Zn2+ on MnO2, MnO2@PSS/PDDA/PSS, and MnO2@(PSS/PDDA)3/PSS was investigated in batch experiments. The adsorption of Zn2+ on MnO2@PSS/PDDA/PSS has been studied under various conditions, such as initial Zn2+ concentration, adsorbent dosage, the solution’s pH, and reaction time. The Zn2+ adsorption process is well represented by the pseudo-second-order kinetic model, and the equilibrium data fit the Freundlich isotherm well. MnO2@PSS/PDDA/PSS also showed high efficiency for Pb2+ and Cu2+ removal from slightly alkaline water. Thus, our research provides a deep insight into the preparation of 3D manganese oxides with polyelectrolyte films for the extraction of heavy metal ions, such as Pb2+, Cu2+, and Zn2+, from slightly alkaline wastewater.

Potential of MnO2‐based composite and numerous morphological for enhancing supercapacitors performance

“…SEM images of (A) nanowire, 131 (B) nanoflower, 132 (C) urchin‐like, 133 (D) nanorods, 134 (E) staghorn coral shape, 135 (F) nanorods, 136 (G) flower‐like, 136 (H) honeycomb‐like, 137 and (I) nanofiber 138 …”

“…Figure 4 shows various MnO 2 morphologies to create supercapacitors and reveals an electrochemical performance improvement whenever morphological alterations are made from one form to another. 131 (B) nanoflower, 132 (C) urchin-like, 133 (D) nanorods, 134 (E) staghorn coral shape, 135 (F) nanorods, 136 (G) flower-like, 136 (H) honeycomb-like, 137 and (I) nanofiber. 138…”