Rational design of thermoresponsive functionalized MCM-41 and their decoration with bimetallic Ag-Pd nanoparticles for catalytic application

MCM-41 was functionalized with thermoresponsive poly (N-isopropyl acrylamide) (p-NIPAM) by free radical polymerization. The surface of the p-NIPAM-coated on MCM-41 (MCM-41/p-NIPAM) nanocatalyst was decorated with bimetallic Ag-Pd nanoparticles for catalytic applications. The nanocatalyst was characterized by X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, nitrogen adsorption/desorption analysis, then mograviametric analysis (TGA), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HRTEM) with energy dispersive X-ray (EDX) spectroscopy, x-ray photoelectron spectroscopy (XPS), and dynamic light scattering (DLS). The thermoresponsive behavior of the synthesized nanocatalyst was analyzed by UV-vis spectroscopy (UV-vis) and DIS analysis. The distribution of bimetallic nanoparticles and their compositions on the polymer-coated mesoporous silica surface were investigated by EDX mapping analysis. The specific surface area was characterized by nitrogen adsorption/desorption analysis. The nanocatalyst was tested for the catalytic reduction of benzaldehyde by UV-vis analysis. Interestingly, the bimetallic nanoparticle-supported MCM-41/p-NIPAM nanocatalyst showed higher activity compared to the other counterparts. In addition, the nanocatalyst showed thermoresponsive behavior at different temperatures and could be recycled for consecutive five cycles with minimal loss in activity. This study is expected to open promising probability for the use of the above material for a range of catalytic applications.