Raspberry-like Pd3Pb alloy nanoparticles: superior electrocatalytic activity for ethylene glycol and glycerol oxidation

Combining Bismuth Telluride and Palladium for High Efficiency Glycerol Electrooxidation

Designing high-performance anodic catalysts to drive glycerol oxidation reaction (GOR) is essential for advancing direct alcohol fuel cells. Coupling Pd with oxophilic materials is an effective strategy to enhance its intrinsic catalytic activity. In this study, we successfully synthesized Pd/Bi2Te3 catalysts with tunable compositions, using Bi2Te3 as a novel promoter, and applied them to the GOR for the first time. Electrocatalytic tests revealed that the activity of the Pd/Bi2Te3 catalysts was closely linked to their compositions. Among these catalysts, the optimized Pd/Bi2Te3-20 % showed potential to replace the commercial Pd/C catalyst, exhibiting a peak current density 5.2 times higher than that of the benchmark Pd/C catalyst. Furthermore, improved catalytic stability and faster catalytic kinetics were observed for Pd/Bi2Te3-20 %. The synergistic effect between Pd and Bi2Te3 is responsible for the high performance of the Pd/Bi2Te3-20 % catalyst.

Cu2+-regulated one-pot wet-chemical synthesis of uniform PdCu nanostars for electrocatalytic oxidation of ethylene glycol and glycerol

The fabrication of effective and stable electrocatalysts is crucial for practical applications of direct alcohol fuel cells (DAFCs). In this study, bimetallic PdCu nanostars (PdCu NSs) were fabricated by a Cu²⁺-modulated one-pot wet-chemical method, where cetyltrimethyl ammonium bromide (CTAB) worked as a structure-regulating reagent. The morphology, compositions, crystal structures and formation mechanism of the as-prepared PdCu NSs were investigated by a series of techniques. The unique architectures created abundant active sites, which resulted in a large electrochemical active surface area (9.5 m² g^-1). The PdCu NSs showed negative shifts in the onset potentials and large forward peak current densities by contrast with those of commercial Pd black for the catalytic ethylene glycol oxidation reaction (EGOR) and glycerol oxidation reaction (GOR). It revealed that the PdCu NSs outperformed Pd black in the similar surroundings. This work provides a constructive strategy for fabrication of high-efficiency electrocatalysts for alcohol fuel cells.

Engineering Heterostructured Pd-Bi2Te3 Doughnut/Pd Hollow Nanospheres for Ethylene Glycol Electrooxidation

The electrooxidation of ethylene glycol (EG) is of vital significance for the conversion from biomass energy into electrical energy via direct fuel cells. However, the EG oxidation reaction (EGOR) suffers from poor efficiency due to the limitation of high-performance electrocatalysts for cleaving the C-C bonds. Herein, this limitation is successfully addressed by fabricating the doughnut-shaped Pd-Bi₂Te₃ heterostructured catalyst. Notably, the heterojunction Pd-Bi₂Te₃ nanocatalyst has been demonstrated to be highly active toward the EGOR with superb activity and durability, in which a mass activity as high as 2420.8 mA mg^-1 is achieved in alkaline media, being 1.7 times higher than that of the commercial Pd/C catalyst. Upon combination of experimental results with mechanism studies, it is indicated that the remarkable EGOR performance is attributed to the enlarged active areas that stemmed from the doughnut-like structure, as well as the strong synergistic effect from Pd-Bi₂Te₃ and Pd. More importantly, the highly electroactive Pd-Bi₂Te₃ can accelerate charge transfer and boost the oxidation of CO-like intermediates, which are conducive to the enhancement in electrochemical stability.

Porous Noble Metal Electrocatalysts: Synthesis, Performance, and Development

Active sites (intrinsic activity, quantity, and distribution), electron transfer, and mass diffusion are three important factors affecting the performance of electrocatalysts. Composed of highly active components which are built into various network structures, porous noble metal is an inherently promising electrocatalysts. In recent years, great efforts have been made to explore new efficient synthesis methods and establish structural-performance relationships in the field of porous noble metal electrocatalysis. In this review, the very recent progress in strategies for preparing porous noble metal, including innovation and deeper understanding of traditional methods is summarized. A discussion of relationship between porous noble metal structure and electrocatalytic performance, such as accessibility of active sites, connectivity of skeleton structures, channels dimensions, and hierarchical structures, is provided.

One-pot synthesis of rugged PdRu nanosheets as the efficient catalysts for polyalcohol electrooxidation

Recently, intensive attention has been attracted to the two-dimensional metal nanosheets, owing to their excellent electrocatalytic performance for direct alcohol fuel cells (DAFCs). Herein, PdRu nanosheets have been synthesized successfully by a facile one-pot method. The rugged nanosheet structure provided plentiful surface active sites to enhance the electrocatalytic activity. Moreover, benefiting from the synergistic effect and improved electronic structure, PdRu NSs exhibited splendid electrocatalytic performance in ethylene glycol oxidation reaction (EGOR) and glycerol oxidation reaction (GOR). Specifically, the mass activity of PdRu NSs was 1.72 and 3.69 times over those of Pd NSs and Pd/C catalysts in EGOR. Moreover, PdRu NSs displayed the largest mass activity in GOR, 1.48 and 2.47 times as large as Pd NSs and Pd/C catalysts. The results of stability tests demonstrated that the durability of PdRu NSs was the highest among the obtained catalysts. This work plays a directive role on the in-depth engineering on Pd-based catalysts with nanosheet architectures.