Preparation and Application of a Hydrochar-Based Palladium Nanocatalyst for the Reduction of Nitroarenes

Abstract

In the present study, a novel heterogeneous catalyst was successfully fabricated through the decoration of palladium nanoparticles on the surface of designed Fe3O4-coffee waste composite (Pd-Fe3O4-CWH) for the catalytic reduction of nitroarenes. Various characterization techniques such as XRD, FE-SEM and EDS were used to establish its nano-sized chemical structure. It was determined that Pd-Fe3O4-CWH is a useful nanocatalyst, which can efficiently reduce various nitroarenes, including 4-nitrobenzoic acid (4-NBA), 4-nitroaniline (4-NA), 4-nitro-o-phenylenediamine (4-NPD), 2-nitroaniline (2-NA) and 3-nitroanisole (3-NAS), using NaBH4 in aqueous media and ambient conditions. Catalytic reactions were monitored with the help of high-performance liquid chromatography. Additionally, Pd-Fe3O4-CWH was proved to be a reusable catalyst by maintaining its catalytic activity through six successive runs. Moreover, the nanocatalyst displayed a superior catalytic performance compared to other catalysts by providing a shorter reaction time to complete the reduction in nitroarenes.

Polyethylenimine as a Versatile Simultaneous Reducing and Stabilizing Agent Enabling One-Pot Synthesis of Transition-Metal Nanoparticles: Fundamental Aspects and Practical Implications

“…Indeed, the values are compatible with the rate constants reported for the catalytic performance of similar transition-metal nanoparticles; ,− nevertheless, the chemical nature of the metallic core, and presumably the morphology of the nanoparticles, notably influence the behavior. The apparent rate constant ( K app ) is roughly 10-fold higher in the presence of PdNPs@BPEI as compared to AgNPs@BPEI.…”

Electrochemical Sensor Based on Spent Coffee Grounds Hydrochar and Metal Nanoparticles for Simultaneous Detection of Emerging Contaminants in Natural Water

“…As shown in Figure 1A, the HDC material exhibits porous, rough and irregular surface morphology, having a honeycomb-like structure with microstructural fragmentation [33,34]. Hydrochars are generally amorphous materials with a low degree of crystallinity [35]. Furthermore, pore formation on its surface is related to reaction time and temperature, and high temperatures are expected to cause an expansion of pores [33].…”

Automated Recognition of Nanoparticles in Electron Microscopy Images of Nanoscale Palladium Catalysts

“…The highest catalyst performance with ~10 9 turnover numbers was recently achieved with Pd/C catalysts [ 8 ]. Representative applications also include sensing [ 9 , 10 ], hybrid nanomaterials design [ 11 , 12 , 13 , 14 ], development of Pd-decorated nanosystems on various forms of carbon [ 15 , 16 , 17 ], and biosynthesis [ 18 ], among many others.…”