Material Science & Engineering World Conference 2026

Abstract

Capacitive deionization (CDI) represents a critical membrane-free electrochemical technology for advanced water purification based on electrosorption within the electrical double layer. This work reports the synthesis and structural engineering of novel composite electrodes based on activated carbon (AC), zinc oxide nanorods (ZnO NRs), and reduced graphene oxide (rGO) deposited onto extruded graphite substrates. A comprehensive multi-scale characterization was carried out utilizing Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Raman spectroscopy, and Brunauer-Emmett-Teller (BET) surface area analysis to correlate the material morphology and porous architecture with its compositional formulation. SEM analysis confirmed the successful anchoring of rod-like ZnO nanostructures within the interconnected AC matrix. Electrochemical performance evaluated via Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) revealed a remarkable increase in specific capacitance, rising from 233.8 F g-1 for AC/ZnO NRs to 342.0 F g-1 upon rGO incorporation, demonstrating enhanced charge transfer kinetics and charge storage capability. Structural evaluation showed specific surface areas of 182 m2 g-1 and 186 m2 g-1 for the binary and ternary composite architectures, respectively. Scaled performance tests in a continuous-flow engineering module containing nine optimized electrode pairs (100 mm x 100 mm active area) with 0.4 M NaCl exhibited a salt adsorption capacity of 9.9 mg g-1 and an energy consumption profile of 6.0 kWh m-3. These findings highlight the significant potential of ternary nano-architecture for scalable, energy-efficient electrochemical desalination technologies.