The critical role of Tween 80 as a ‘green’ template on the physical properties and photocatalytic performance of TiO2 nanoparticles for Rhodamine B photodegradation

A popular non-toxic surfactant, Tween 80 (T80), is widely used in foods, cosmetics, and pharmaceuticals. This eco-friendly surfactant should be promising to be utilized as a non-ionic template in the preparation of TiO2 nanoparticles. Moreover, few studies deal with Tween 80 as a template in the synthesis of various nanoparticles. Different concentrations of T80/isopropanol solutions (0–50%) were used in a modified template-assisted sol–gel route, where the synthesized xerogels were denoted by x%T80-TiO2. Different techniques such as DRS, XRD, SEM, HR-TEM, and N2 adsorption–desorption isotherms were utilized to characterize the as-prepared x%T80-TiO2 catalysts. The obtained results showed that the whole physical properties, such as crystalline parameters, optical properties, micromorphology, nanomorphology, and surface parameters, were affected by the concentration of T80 (T80%). In addition, T80% significantly changed the photoactivity of the synthesized samples toward the photodegradation of Rhodamine B (RB) as a pollutant model. 5%T80-TiO2 nanoparticles were the most reactive catalyst referring to its unique rod structure and existence of a small content of Rutile phase. Finally, tetra (4-carboxyphenyl) porphyrin (TCPP) was anchored on TiO2 nanorods to be used as a visible antenna to enhance its photocatalytic activity toward the visible light irradiation. Briefly, TCPP-sensitized T80-TiO2 nanoparticles showed an enhanced performance toward the degradation of RB under various light sources.