Akademik Veri Yönetim Sistemi
Ceramics International, 2026 (SCI-Expanded, Scopus)
MnO2-coated TiO2 nanotube arrays were fabricated on titanium plates via electrochemical anodization followed by sol–gel spin coating using precursor concentrations of 5, 25, and 50 mM. Comprehensive analyses were conducted to evaluate the structural, morphological, optical, and surface wettability characteristics of the samples. Additionally, their photocatalytic efficiency in degrading methylene blue (MB) under visible light was evaluated. While X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) measurements revealed the coexistence of anatase TiO2 and crystalline MnO2 phases, scanning electron microscope (SEM) analysis confirmed the preservation of the well-ordered nanotubular shape following MnO2 deposition. UV–Vis diffuse reflectance spectroscopy revealed that MnO2 coating reduced the band gap to 3.05 eV, thereby enhancing visible-light absorption. MnO2-coated samples exhibited a significant decrease in emission intensity according to photoluminescence spectroscopy, suggesting that charge carrier recombination was suppressed. Under visible light, the 25 mM MnO2-coated TiO2 nanotubes demonstrated the best photocatalytic activity of all the compositions, removing 85.56 % of the MB in 8 h. Compared to previous MnO2/TiO2 studies predominantly employing nanoparticles or bulk coatings, this work demonstrates that conformal MnO2 layers can be directly deposited onto ordered TiO2 nanotubes using a simple and scalable spin-coating process. This strategy enhances visible-light photocatalytic performance by enabling optimal light–matter interactions and tunable MnO2 loading, highlighting the potential of MnO2-modified TiO2 nanotubes as efficient and durable photocatalysts for wastewater treatment.