Porous Metal Organic Framework (MOF) derived dimorphic (n-ZnO/p-NiO) Z-scheme heterojunction anchored with MWCNTs (ternary nano-architecture): A novel approach for optimization of photodegradation mechanism and kinetics of Congo red (CR) dye

Abstract

Global efforts to combat water pollution, especially from organic dyes like Congo red, emphasize the use of advanced nanomaterials for sewage purification. Metal-Organic Frameworks (MOFs), known for their crystalline structures and versatile properties, have become pivotal in wastewater treatment research. Integrating MWCNTs into MOF derived composite nanostructures is a strategic advancement, boosting the efficiency of photocatalytic systems and addressing environmental concerns. This study details the synthesis of a novel Z-scheme heterojunction nanocomposite (n-ZnO/p-NiO) incorporating multi-walled carbon nanotubes (MWCNTs), achieved via a solvothermal method using metal-organic framework (MOF) as a template. The study uses XRD, FTIR, FESEM, BET, UV, and PL for comprehensive nanocomposite characterization, offering insights into its structural, morphological, and optical properties. The resultant nanocomposite displays high surface area, sturdy pore arrangement, and consistent morphology. MWCNTs influence crystal growth and optical absorption, enhancing surface hydroxyl group concentration and acting as electron acceptors. This results in decreased photo oxidation and improved overall stability under light exposure in the composite. The composite achieves 92 % Congo red degradation in 60 min under UV light, showcasing superior dye adsorption capacity. This underscores its potential as an efficient photocatalyst for environmental remediation and wastewater treatment.