Catalytic reduction in 4‐nitrophenol using Actinodaphne madraspatana Bedd leaves‐mediated palladium nanoparticles

Abstract

There is a growing demand for the development of non-toxic, cost-effective, and environmentally benign green synthetic strategy for the production of metal nanoparticles. Herein, the authors have reported Actinodaphne madraspatana Bedd (AMB) leaves as the bioreducing agent for the synthesis of palladium nanoparticles (PdNPs) and its catalytic activity was evaluated for the reduction of 4-nitrophenol (4-NP) to 4-aminophenol with undisruptive effect on human health and environment. The broad and continuous absorbance spectrum obtained in the UV-visible region indicated the formation of PdNPs. The synthesized PdNPs were found to be crystalline, spherical, and quasi-spherical in shape with an average particle size of 13 nm was confirmed by X-ray diffractometer and transmission electron microscope. Fourier transform infrared spectra revealed the active photo constituents present in the aqueous extract of AMB involved in the bioreduction of palladium ions to PdNPs. The catalytic activity of biosynthesized PdNPs was demonstrated for the reduction of 4-NP via electron-relay process. Also, the influential parameters such as catalyst dosage, concentration of 4-NP, and sodium borohydride were studied in detail. From the present study, PdNPs were found to be a potential nanocatalyst for nitro compound reduction and also for environmental remediation of wastewater effluents from industries.

Rapid Catalytic Reduction of 4-Nitrophenol and Clock Reaction of Methylene Blue using Copper Nanowires

“…The decreasing trend in k app could be due to the competition between the two reactants (4-NP and BH 4 − ) to occupy the surface of CuNWs. Higher concentration of 4-NP has higher affinity to adsorb on the surface of CuNWs compared to BH 4 – ion and this lessen the occupancy sites of BH 4 – [57]. Liberation of hydrogen at the surface of CuNWs was limited due to the decreasing occupancy sites of BH 4 – [58].…”

“…Hence, the competition between 4-NP and BH 4 – would be less which resulted in a faster reaction with higher rate constant values. Lower reduction rate at higher concentrations of 4-NP is observed due to the poor electron delay between the reactants [57].…”

Selective catalysis in a cellular microenvironment—a living cell catalytic system with intracellular nanopalladium for olefin hydrogenation

“…The zeta potential value of bio-nPd separated from the LCCSs is −41.7 mV in phosphate buffer ( pH 7), indicating that the bio-nPd possess good dispersibility and stability in the colloidal state (Fig. 1B), [34][35][36] which is further demonstrated by the obvious Tyndall effect (inset of Fig. 1B).…”

Sustainable magnetically recoverable Iridium-coated Fe3O4 nanoparticles for enhanced catalytic reduction of organic pollutants in water

“…The rate equation is given as: ln (Ct/Co) = -kt where Ct is the absorbance of 4-NP at time t, Co is the initial absorbance of 4-NP and k is the rate constant (Priya and Asharani 2018) The effect of temperature on the degradation of 4-NP was studied at 40 о C, 50 о C, and 60 о C (Table 1). At 40 о C, the reaction was completed in 5 min with an apparent rate constant as 0.456 min -1, and on increasing the temperature to 50 о C, 60 о C, the reaction was completed in 4 min with kapp as 0.4741 min -1 and in 3 min with kapp as 0.7262 min -1 respectively.…”