Role of surfactant type on morphological, textural, optical, and photocatalytic properties of ZnO nanoparticles obtained by modified sol–gel

In our study, we focused on the optimization of synthesis ZnO nanoparticles by modified sol–gel method using ZnCl2 as precursor and two different surfactants cetyltrimethylammonium bromide (CTAB) as cationic and triblock copolymer pluronic (EO106 PO70 EO106, F127) as the nonionic one. Therefore, the addition of two organic surfactants is important due to their influence on physicochemical properties. From analysis, the ZnO synthesis parameters were optimized using the response surface methodology (RSM) for optimal recoveries of synthesis. In fact, the structural, crystallite size, morphological, thermal stability, surface area, and optical properties of the ZnO nanoparticles are well characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Nitrogen adsorption-desorption N2, UV–visible and photoluminescence PL. The XRD confirms the formation of pure wurtzite ZnO phase with crystallite size in the range of 27.6–36.6 nm, SEM and TEM shows spherical and nanobattonet ZnO particles depending of surfactant used. From the optical studies, it is found that the band gap energy increase from 3.10 to 3.18 eV with the increase in the surfactant concentrations of CTAB and pluronic F127. The effects of type surfactant on the photocatalytic activity of ZnO nanoparticles were examined by the degradation of Rhodamine B in water under UV irradiation and sunlight. As a result, ZnO has higher photocatalytic activity for the degradation of Rhodamine B under UV irradiation and sunlight. This process was described by the pseudo-first-order kinetic model and Z2F which prepared with pluronic F127 has an excellent response after degradation.