Rational synthesis of ternary PtIrNi nanocrystals with enhanced poisoning tolerance for electrochemical ethanol oxidation

The development of highly efficient and durable anode materials for ethanol electro-oxidation remains a challenge. Herein, we report the synthesis of Pt _1−x−y Ir _x Ni _y nanocrystals via one-step procedure by ultrasonic-assisted co-reduction of the metal precursors using ascorbic acid as a mild reducing agent and pluronic F127 as a structure directing agent. The catalytic performance of this ternary catalyst towards electrochemical oxidation of ethanol was examined and compared to its mono and binary Pt counterparts (Pt, Pt _1−x Ir _x , and Pt _1−y Ni _y ) that are synthesized by the same method. TEM analysis showed a porous nanodendritic structure for the synthesized ternary electrocatalyst with an average size of 20 ± 1 nm. The electrochemical measurements revealed an electrochemically active surface area, ECSA, of 73 m ² g ⁻¹ . The as-synthesized ternary electrocatalyst showed an improved catalytic activity towards ethanol oxidation in 1 M KOH with a measured mass activity of 3.8 A mg ⁻¹ which is 1.7, 2.0, and 3.2 times higher than that of Pt _1−x Ir _x , Pt _1−y Ni _y , and Pt, respectively. Additionally, the Pt _1−x−y Ir _x Ni _y nanocrystals expressed high poisoning tolerance (j _f /j _b = 4.5) and high durability compared to its mono and binary counterparts.