Effect of Hexadecylpyridinium Bromide (HDPB) on Morphology and Electrocatalytic Performance of Porous Palladium Nanoparticles

Abstract

AbstractStructure‐controlled synthesis of palladium nanoparticles has long been a hot subject because of their remarkable catalytic performance. Herein, hexadecylpyridinium bromide (HDPB) was introduced as capping agent in the preparation of Pd nanoparticles (PdNPs) through a facile none‐seeded routine using Na2PdCl4 as precursor. The as‐prepared PdNPs was in the shape of flocculus and it had a highly porous feature with an average size of 53.1 nm. The morphology evolution along with time was investigated by transmission electron microscopy and a possible formation mechanism of PdNPs was proposed. Meanwhile, the structural changes of PdNPs along with the concentration of HDPB and temperature were also studied. The relationship between structure and electrocatalytic activity were discussed. The electrocatalytic performance of PdNPs was much superior than commercial Pd/C toward methanol electro‐oxidation in the alkaline medium. The optimum electrocatalytic activity (jf=19.4 mA cm−2) was obtained catalyzing by PdNPs synthesized when n(HDPB)/n(Pd2+)=0.6 : 1 at 50°C for 3 h.