Counterion engineered surfactants for the novel synthesis of colloidal metal and bimetal oxide/SiO ₂ materials with catalytic applications

Surfactants with modified counterions consisting of transition metals and lanthanides are relatively new and not much explored in terms of the possibilities of their applications. Herein, we reported the room temperature synthesis of the colloidal dispersions of metals and bimetal (Cu, Ni, Cu-Ni) oxide/SiO ₂ particles following a single-step in-situ protocol. The procedure simply involved hydrolysis and condensation of tetraethyl orthosilicate (TEOS) in the presence of a cationic surfactant with modified counterions. The synthesized materials were characterized with the help of field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), powder x-ray diffraction, (P-XRD), and energy dispersive x-rays (EDX) spectroscopy. Furthermore, the catalytic performance of the synthesized dispersions of different nature was evaluated using a UV–vis (UV–vis) spectrophotometer. It was found that metal counterions could be effectively employed to tune the catalytic properties of the resulting material.