Tailoring Photocatalytic Efficiency: DFNS/WO3 Nanocomposite with Engineered Interface for Enhanced Oxygen Evolution

Abstract

Here, we report the synthesis of novel DFNS/WO₃ photocatalysts through a hydrothermal method. A thorough exploration of the crystal phase purity, optical absorption properties, and morphology of DFNS/WO₃ was undertaken, employing techniques such as powder X-ray diffraction (P-XRD), ²⁹Si cross-polarization magic angle spinning NMR (²⁹Si CPMAS NMR), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), ultraviolet-visible diffuse reflectance spectroscopy (UV-DRS), and Brunauer–Emmett–Teller (BET) analysis. This comprehensive characterization revealed the existence of a distinctive interface between WO₃ nanoparticles and the dendritic fibrous nanosilica (DFNS) surface. In photocatalytic water-splitting experiments, the DFNS/WO₃ nanocomposite, featuring 7 wt% of WO₃ on DFNS, demonstrated a remarkable increase in oxygen evolution rate (1863 μmol h^–1 g^–1_cat) compared to pure WO₃ (361 μmol h^–1 g^–1_cat), marking a notable five-time improvement. This study presents an innovative approach to developing an efficient photocatalytic system by incorporating DFNS/WO₃ nanocomposites, where WO₃ possesses an optimal band gap of 2.96 eV, making it highly suitable for photocatalytic water splitting. The DFNS/WO₃ photocatalyst demonstrates remarkable catalytic activity, stability, and reusability, addressing key considerations for practical applications. This study provides an innovative strategy for designing advanced photocatalytic systems capable of efficient and sustainable oxygen evolution under visible light.