Self-assembled palladium nanoflowers supported on fullerene: Electrochemical catalytic performance for the reduction of 4-nitrophenol

Abstract

Loading metal nanoparticles on the surface of nanosheet supports is an attractive approach to enhancing their catalytic performance. Herein, palladium nanoflowers (Pd NFs) were prepared on amino-functionalized fullerene (C60-NH2) by hydrothermal self-assembly using ethylenediamine (EA). Reduction of Pd ions resulted in the formation of Pd nanoflowers with a fullerene bottom layer and Pd petals. Ethylenediamine, a functionalized fullerene precursor, afforded a nitrogen-rich fullerene that ensures strong interactions between Pd2+ and functionalized fullerene and improves the chemical and morphological stability of the resulting Pd nanoflowers. Compared with spherical Pd nanoparticles supported on amino-functionalized fullerene (C60-NH2), the Pd nanoflowers (Pd NFs/C60-NH2) exhibit greatly superior activity towards the reduction of 4-nitrophenol (4-NP). The nanoflowers exhibit not only a remarkable UV–vis response for the conversion of 4-nitrophenol to 4-aminophenol (4-AP) (99% in 2.0 min) with a turnover frequency of 12.35 min−1 but also a high electrochemical sensitivity to 4-nitrophenol over a wide linear concentration range (5–1000 μM), providing a detection limit of 0.09 μM (S/N = 3) at room temperature. The excellent catalytic stability and durability of Pd NFs/C60-NH2 offer promising applications in catalysis. Keywords: 4-Nitrophenol reduction, Fullerene (C60), Self-assembly, Pd nanoflowers