Synthesis of Pd₃Sn and PdCuSn Nanorods with L1₂ Phase for Highly Efficient Electrocatalytic Ethanol Oxidation

Abstract

The crystal phase of nanomaterials is one of the key parameters determining their physicochemical properties and performance in various applications. However, it still remains a great challenge to synthesize nanomaterials with different crystal phases while maintaining the same composition, size, and morphology. Here, a facile, one‐pot, wet‐chemical method is reported to synthesize Pd3Sn nanorods with comparable size and morphology but different crystal phases, that is, an ordered intermetallic and a disordered alloy with L12 and face‐centered cubic (fcc) phases, respectively. The crystal phase of the as‐synthesized Pd3Sn nanorods is easily tuned by altering the types of tin precursors and solvents. Moreover, the approach can also be used to synthesize ternary PdCuSn nanorods with the L12 crystal phase. When used as electrocatalysts, the L12 Pd3Sn nanorods exhibit superior electrocatalytic performance toward the ethanol oxidation reaction (EOR) compared to their fcc counterpart. Impressively, compared to the L12 Pd3Sn nanorods, the ternary L12 PdCuSn nanorods exhibit more enhanced electrocatalytic performance toward the EOR, yielding a high mass current density up to 6.22 A mgPd−1, which is superior to the commercial Pd/C catalyst and among the best reported Pd‐based EOR electrocatalysts.

Synthesis of Alloyed Pd−Pb Nanowire Networks for Electrocatalytic Ethanol Oxidation with High Stability

“…Since the electronegativity of Pb is higher than that of Pd, the d-band center of the Pd atom will change due to the transfer of electrons from Pd to Pb during the formation of the alloy, which would weaken the adsorption of toxic intermediates on the catalyst surface and thus lead to the enhancement of the activity of electrocatalytic oxidation of ethanol. [59][60][61][62][63] In general, the introduction of lead leads to the change of electronic structure of palladium, which increases the catalytic activity of the alloy. [57] The electrocatalytic activities of PdÀ Pb NNWs were evaluated by electrochemical measurements.…”

Constructing Structurally Ordered High‐Entropy Alloy Nanoparticles on Nitrogen‐Rich Mesoporous Carbon Nanosheets for High‐Performance Oxygen Reduction

“…The ordering-promoted catalytic performance enhancement has been widely investigated in the systems of bi-and trimetallic electrocatalysts (e.g., PtCo, PtFe, and PdCuSn). [24][25][26][27][28] Nevertheless, the synthesis of structurally ordered HEA (OHEA) NPs and evaluation of their impacts on the catalytic performance have yet been achieved.…”

Surface‐Decorated High‐Entropy Alloy Catalysts with Significantly Boosted Activity and Stability

“…[28,62] We used ethanol oxidation reaction (EOR), the anode reaction in the direct ethanol fuel cell, [63][64][65] as a model reaction to demonstrate the utility of surface-decorated HEA catalysts. Ethanol oxidation to CO 2 and H 2 O is a complex multi-electron transfer process involving dissociative adsorption, C-H and C-C bond activation, as well as carbon monoxide (CO) oxidation, [66][67][68] which is an ideal model reaction to test the effectiveness of our HEA design. Indeed, NHEA@NHEA-Pd exhibited a high mass activity of 7.34 A mg −1 Pd , excellent stability (>91.8% retention after 2000 cycles), and enhanced CO tolerance, indicating the critical role of high-entropy coordination and morphological control in HEA catalysts toward improved activity, stability, as well as significantly reduced cost.…”