Integration of ZnO into Polyhedral Oligomeric Silesquioxane (POSS) for Enhanced Adsorption and Removal of Malachite Green Dye from Aqueous Solution

An enhanced inorganic–organic hybrid material known as polyhedral oligomeric silesqioxane (POSS) cross linked with glutaraldehyde and further incorporation of zinc oxide nanoparticles (ZnO Nps) has been accomplished to use it as an adsorbent to remove the cationic dye i.e., malachite green (MG) from water. To analyze the features of synthesized adsorbent, it was further characterized by PXRD, SEM, FTIR, FESEM, TGA, BET, and HRTEM. The obtained results correspond to the formation of spherical morphology for the created POSS material, while small spheres suggest the presence of ZnO NPs on the POSS material. The nanoparticle-based adsorbent was further utilized as an adsorbent for MG dye, and the adsorption study was extended with various factors like adsorbent dose, pH, agitation time, and dye concentration. Adsorption kinetics and isotherm data were well analyzed via pseudo-first-order reaction and Langmuir adsorption isotherm. The maximum adsorption capacity observed for the MG dye was 78.125 mg g⁻¹. The desorption study was also done by using methanol as well as HCl and regeneration of the adsorbent was studied by the repetitive cycles. The adsorption analysis suggests that the synthesized ZnO@Glu@POSS can be referred to as a novel adsorbent, which is effective in removing MG dye from the aqueous solution.