Precisely Tuning the Surface Nanostructure of Ni@Pd Nanocatalysts for Enhanced Formic Acid Oxidation

Abstract

Constructing Ni@Pd nanocatalysts can effectively improve the catalytic efficiency of Pd atoms. However, it is difficult to grow Pd atoms uniformly on the Ni surface due to the large lattice mismatch between Ni and Pd. Herein, we demonstrate that the well-defined Ni@Pd nanocatalysts can be obtained by the galvanic replacement reaction between Ni and Pd at room temperature. By simply regulating the content of Pd precursor in the galvanic replacement reaction, the atomic percentages of Pd can be controlled from 2 % to 9 %. In synthesized Ni@Pd nanocatalysts, the Ni@Pd 0.06 core-shell nanocrystals show the highest mass activity (1186 mA mg Pd À 1 ) and specific activity (4.21 mA cm À 2 ), which are 5.6 times and 2.6 times higher than that of the commercial Pd/C nanocatalyst (212 mA mg Pd À 1 , 1.60 mA cm À 2 ). The enhanced performance is mainly attributed to the synergistic effect between Pd and Ni and the core-shell nanostructure.

Electrochemical Oxidation of Formic Acid on PdM (M=Cr, Mn, Fe, Co, Ni, and Ag) Alloy Nanoparticles with Low M Content: A Comparative Study

“…Table 5 compares the results of the current investigation with those of earlier studies. The highest mass activity (1980 mA g −1 Pd ) obtained for the PdAg sample in this work is higher than that of the Pd/xCuO‐CNT, [17] Pd 6.3 Cd, [45] ordered Pd3Fe/C, [99] PdFe alloy, [100] CuPd@Pd, [109] Twisted Pd‐Cu nano chain, [116] PdCu Nanocatalysts, [117] Pd/rGO, [118] Pd NCNs, [119] Pd@N‐C NFs, [120] Pd 30 La 70 /rGO, [121] Ni@Pd 0.06 core‐shell nanocrystals, [122] and Pd/GA [123] samples. Furthermore, the mass activity of the PdAg sample is larger than the commercial Pd/C values of 0.49 A g −1 Pd , [36] 0.3 A g −1 Pd , [95] 0.53 A g −1 Pd , [109] and 0.24 A g −1 Pd [116] …”

Tuning the surface structure of Cu2O@Pt for enhanced ethanol electrooxidation

“…For a core–shell catalyst, because the core and shell have different characteristic peaks in X-ray diffraction (XRD), their nanostructures can be well characterized by XRD. 37 As shown in Fig. 2, the X-ray diffraction peaks of both Cu 2 O and Pt can be detected.…”

“…For a core-shell catalyst, because the core and shell have different characteristic peaks in X-ray diffraction (XRD), their nanostructures can be well characterized by XRD. 37 As shown in Fig. 2 When Pt atoms are replaced on the surface of Cu 2 O by galvanic replacement reaction, the electronic structure of Pt atoms will change due to the different electronegativity between copper and platinum.…”

Indium-doped flower-shaped PdIn nanocatalysts for enhanced ethanol oxidation

“…16 By regulating the electronic structure and composition of palladium-based catalysts, the adsorption energy of intermediate products can be effectively reduced, thus improving the catalytic efficiency of palladium-based catalysts. 17 Among the modification methods of palladium-based nanocatalysts, core-shell, 18,19 alloy, 20 phase engineering, 21,22 interface engineering, 23 metal-organic frameworks [24][25][26][27] and doping 28 can effectively improve the catalytic performance of palladium atoms. Among them, doping is a very effective modification method.…”