Titania nanotube stabilized BiOCl nanoparticles in visible-light photocatalysis

Photocatalysis is a green approach in environmental organic pollutant decomposition. Lately, considerable improvement in the activity of photocatalysts has been achieved with the realization of p-n heterostructures due to the lifetime extension of the photogenerated charge carriers. Herein, we report a facile synthesis approach for decorating n-type titanate nanotubes with p-type V-VI-VII compound semiconductor BiOCl nanoparticles. It is well-known that BiOX ( X = Cl, Br, I) materials form nanometer-thick platelets, which can eventually assemble into micrometer size flower-like 3D structures. Here, we demonstrate that the tubular titanate support can stabilize BiOCl on its surface in the form of nanoparticles measuring a few nanometers in diameter, instead of forming the well-known bismuthoxyhalide nanoflowers. Subsequent calcination at 400 degrees C transforms the pristine titanate structures into one-dimensional anatase nanotubes, along with the formation of a heterojunction at the interface of the emerging Bi2Ti2O7 and anatase phases. The resulting nanocomposite shows activity in visible-light photocatalytic test reactions.