Degradation of methylene blue using inutile LCD panels as novel anodes: A potential replacement for platinum-based electrodes

Abstract

Conventional methods of wastewater treatment are often insufficient for effectively treating textile dyes and effluents, leading to poor water quality in the receiving water bodies. To combat this, an electrochemical advanced oxidation process, namely the electro-peroxone process, has been proven to be very promising for wastewater treatment. In this study, a carbon-based cathode, reticulated vitreous carbon (RVC), and a novel anode repurposed from an obsolete desktop liquid crystal display (LCD) unit were evaluated for their performance in the electro-peroxone process for the removal of methylene blue dye and wastewater contaminants. This is supported by FTIR, TGA, and XRD characterization techniques of LCD, as well as BET and TGA analysis of RVC. The •OH formation is verified using ESR. Additionally, the performance of the LCD electrode was compared with that of a standard platinum-coated titanium electrode, and the effects of various electrolytes (Na2SO4, NaCl, K2SO4) were examined to understand their influence on degradation efficiency. The results showed that K2SO4 enabled the highest dye degradation (95.36%), while Na2SO4 and NaCl achieved ∼90% degradation. The LCD electrode achieved a removal efficiency of ∼95%, closely approaching the complete removal achieved by Pt/Ti, suggesting its strong potential as a practical substitute. Real wastewater treatment further demonstrated the effectiveness of the system, achieving 30% TOC mineralization, a 75% reduction in COD, an 80% reduction in turbidity, and a 57% reduction in TSS in 6 h. Overall, the results demonstrated that the LCD-RVC electro-peroxone system provided robust pollutant removal, confirming LCD as a promising low-cost electrode material for advanced oxidation applications. © 2026