Facile synthesis of novel hierarchical TiO2@Poly(o-phenylenediamine) core–shell structures with enhanced photocatalytic performance under solar light

• Synthesis of conducting TiO2@PoPD core–shell nanocomposites by chemical oxidative polymerization.
• TiO2 nanoparticles were surrounded by uniform thin PoPD film and the particles are well dispersed in the PoPD matrix.
• TiO2@PoPD core–shell nanocomposites have a broad and strong absorption in visible range.
• Remarkable enhancement in the photodegradation rate of Rhodamine B dye was observed for TiO2@PoPD nanocomposites than for TiO2 under solar irradiation.

The present work describes a novel contribution to the development of a new photocatalyst based on titanium dioxide (TiO2)@poly(o-phenylenediamine) (PoPD) core–shell nanocomposites for the mineralization of Rhodamine B (RB) dye under sun light irradiation. The core–shell feature of the nanocomposites was proved by Atomic Force Microscopy (AFM) and Transmission Electron Microscopy (TEM). Ultraviolet–visible Diffuse Reflectance Spectra (UV–vis DRS) revealed that TiO2@PoPD core–shell composites show broad and stronger absorption than TiO2 in the whole range of visible light indicating the sensitizing effect of PoPD. Structure of the TiO2@PoPD nanocomposite was confirmed by Fourier Transform Infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) pattern. The hybrid photocatalysts possess dramatic photocatalytic activity for the degradation of the RB under solar light irradiation. A plausible pathway and mechanism for the photocatalytic degradation of RB was also discussed.

The present study shows synthesis and fabrication of TiO2@PoPD core–shell nanocomposites by chemical oxidative polymerization for solar light photocatalysis. The TiO2@PoPD core–shell nanocomposites were produced with pre-aggregated or glued titanium in the cores (inside black components) and polymer in the shells (outside white components); the entire surface of the TiO2 particles was surrounded by uniform thin PoPD film layer and the TiO2 nanoparticles are well dispersed in the polymer matrix. The TiO2-PoPD core–shell nanocomposites possess dramatic photocatalytic activity for the degradation of the RB under solar light irradiation.Figure optionsDownload as PowerPoint slide