Degradation of PCP-Na with La–B co-doped TiO2 series synthesized by the sol–gel hydrothermal method under visible and solar light irradiation

A series of photocatalysts was synthesized by doping TiO2 with La and B via the sol–gel hydrothermal route. The photocatalytic capability of the catalysts under visible and solar light was evaluated in terms of sodium pentachlorophenate (PCP-Na) decomposition and dechlorination. The structural and physicochemical properties of these nanocatalysts were characterized by XRD, DRS, ICP-OES, TEM, XPS, and N2 adsorption–desorption techniques. B doping enlarged the anatase framework, and La doping hindered the crystallization and growth of the mesoporous structure in both singly La-doped and La–B co-doped catalysts. B implantation mainly resulted in visible-light response, whereas overload La2O3 coating worsened visible light absorption, as confirmed by DRS and XPS. XPS and ICP-OES analyses revealed that the B and La content increased approximately by 1.6 and 4.8 times from the interior to the surface of modified TiO2, which dominantly existed in the form of La2O3 and interstitial B structure. The co-doped sample with 1% La and 5% B doping (LA10B50) exhibited maximum photocatalytic activity under visible and solar light compared with the mono-doped samples, which was attributed to synergetic effects, namely, efficient separation of photo-generated carriers by La and response to the extended visible region due to B. An increase in hydroxyl groups and the photosensitivity of carbon on the surface also contributed to the improvement of photoactivity.

A series of novel photocatalysts was synthesized by doping TiO2 with La and B via the sol–gel hydrothermal route. The co-doped sample exhibited maximum photocatalytic capability under visible and solar light in terms of PCP-Na decomposition and dechlorination. Schematic illustration of the photocatalysis by the La–B co-doped catalyst under solar light irradiation is shown.Figure optionsDownload high-quality image (127 K)Download as PowerPoint slideHighlights
► Novel La–B–TiO2 synthesized by sol–gel hydrothermal route with high activity.
► Efficient decomposition and dechlorination of PCP-Na under visible and sun light.
► Synergetic effects of La and B implantation.
► Variation of catalytic activity with the action of the dopants in modified system.