Insights into the Role of Poly(vinylpyrrolidone) in the Synthesis of Palladium Nanoparticles and Their Electrocatalytic Properties

Abstract

Four types of palladium (Pd) nanoparticles were prepared from the systems containing PdCl2 or Na2PdCl4 with or without the assistance of poly­(vinylpyrrolidone) (PVP). Two types of Pd nanoparticles obtained in the absence of PVP were obviously larger than those synthesized with the assistance of PVP. The former large Pd particles showed typical features in cyclic voltammetry in H2SO4 solution, whereas two types of small Pd nanoparticles did not. However, small nanoparticles treated first in an electrochemical way in 0.5 M KOH solution displayed the adsorption and desorption peaks similar to those of typical Pd-modified electrodes in H2SO4 solution. Large Pd nanoparticles from the PdCl2 synthesis system showed a catalytic specific current of 629 mA/mg in the electrocatalysis of ethanol, whereas large particles from the Na2PdCl4 system showed a current of 262 mA/mg. The maximum catalytic currents of small Pd nanoparticles without surface cleaning treatment were 1382 and 1019 mA/mg for samples from the Na2PdCl4 and PdCl2 systems, respectively, higher than those being treated in KOH solution first, and the electrocatalytic stability of the two untreated samples was better. However, small nanoparticles after the electrochemical treatment can reach the maximum catalytic current faster. The synthesis and structure–property relation of four types of Pd nanoparticles have been discussed and analyzed on the basis of systematically experimental data.

Preparation of Palladium Nanoparticles Decorated Polyethyleneimine/Polycaprolactone Composite Fibers Constructed by Electrospinning with Highly Efficient and Recyclable Catalytic Performances

“…The kinetic constant k of the above catalytic reduction reaction was calculated to be 0.16597s −1 and 0.00401 s −1 , respectively. The kinetic constant k could intuitively reflect the speed of the catalytic reduction reaction [58][59][60][61][62][63][64][65]. Obviously, PEI/PCL@PdNPs catalytically reduced 4-NP faster.…”

A facile preparation method for new two-component supramolecular hydrogels and their performances in adsorption, catalysis, and stimuli-response

“…Thus, present obtained composite hydrogels demonstrated a new clue for the design of self-assembled nanomaterials and organized composites. [54][55][56][57][58][59][60][61][62][63][64][65]…”

Preparation of Self-Assembled Composite Films Constructed by Chemically-Modified MXene and Dyes with Surface-Enhanced Raman Scattering Characterization

“…Sarycheva et al reported the utilization of MXene as a SERS substrate for detecting several common dyes with calculated enhancement factors on the level of 10 6 [33]. Compared to the above works, present prepared composite films via self-assembled LB approach showed good SERS performance with simple and organized process, demonstrating potential applications in SERS detections and composite materials [69,70,71,72,73,74,75,76,77].…”