Ultrafine two-dimensional alloyed PdCu nanosheets-constructed three-dimensional nanoflowers enable efficient ethylene glycol electrooxidation

Constructing efficient catalysts for the electrooxidation of fuels is of vital importance for realizing the commercialization of fuel cells. Unfortunately, most of catalysts (e.g. Pt) suffer from limited activity and poor durability for the electrooxidation of liquid fuel. Also, the drawbacks of extremely high cost and nature scarcity have also severely hindered their large-scale applications. Here, we demonstrated the synthesis of a new class of well-defined and three-dimensional (3D) flower-like nanocatalysts which assembled by ultrafine two-dimensional (2D) alloyed PdCu nanosheets. Structurally, the as-obtained PdCu alloy nanoflowers (NFs) possessed high surface area with abundant surface active sites. Benefiting from the unique structural properties and the strong alloy effect, the as-obtained PdCu NFs can display greatly enhanced performances toward ethylene glycol oxidation reaction (EGOR) with the mass/specific activity of 4714.1 mA mg⁻¹/13.7 mA cm⁻², which are 4.4 and 6.85 times of Pd/C catalysts, respectively. Most strikingly, such 2D nanosheets-constructed 3D nanoflower-like structure also enables the PdCu catalysts with high long-term stability for EGOR. As a proof of concept, this work not only presents the rational design and construction of catalysts with well-defined structure for the fuel cells reactions but also provides a promising method to largely promote the electrochemical performances of catalysts.