Computational and Experimental Design of the Octahedral PdFe Alloy Nanocatalyst for Hiyama Cross-Coupling and Environmental Pollutant Degradation

Abstract

The research on various bimetallic nanoparticles (NPs) is rapidly expanding due to their widespread applications. However, the formation of bimetallic nanostructures in a facile way remains challenging. In the present study, an octahedral (Oh) PdFe alloy nanostructure was designed by following an aqueous medium synthesis strategy. Different metal precursor ratios were varied to observe the change in the shape and distribution of the Oh PdFe alloy nanostructure. Surprisingly, increasing the Fe content directed the finer growth of Oh morphology. However, increasing the Pd amount resulted in an uneven Oh PdFe alloy shape. The catalytic activity of the optimized Oh PdFe alloy was examined for Hiyama cross-coupling, and the degradation of dyes was scrutinized at different pH. The suggested alloy nanostructured catalyst exhibited improved catalytic behavior compared to other nanocatalysts, such as commercial catalyst Pd/C (95%), monometallic Pd Oh (98%), Fe NPs (15%), and PdFe NPs (85%), for the Hiyama cross-coupling reaction. The optimized alloy catalyst with less Pd and more Fe demonstrated 98% yield and excellent reusability up to the fifth consecutive cycle, conveying 80% yield. The stability of the Oh PdFe alloy nanocatalyst and the mechanistic aspects of Hiyama cross-coupling was supported by density functional theory. The degradation of both anionic dyes, Congo red, Eosin Y, and cationic rhodamine B, was performed under normal along with acidic and basic conditions. The degradation reaction was completed in an adequate time interval for all the dyes with no change in the morphology of the synthesized catalyst.