One-Pot Seedless Aqueous Synthesis of Reduced Graphene Oxide (rGO)-Supported Core-Shell Pt@Pd Nanoflowers as Advanced Catalysts for Oxygen Reduction and Hydrogen Evolution

Abstract

Herein, reduced graphene oxide supported core-shell Pt@Pd nanoflowers (Pt@Pd NFs/rGO) were fabricated by a single-step, seedless wet-chemical approach at room temperature, only using 3-aminopyrrolidine dihydrochloride (APDC) as the weak stabilizer and structure director. The morphology, structure, and composition of the product were characterized by a series of characterization techniques, and the formation mechanism was discussed in detail. The nanocomposite exhibited improved catalytic activity for oxygen reduction reaction (ORR) with the positive onset potential (Eonset, 0.91 V vs. RHE) and half-wave potential (E1/2, 0.82 V vs. RHE), and hydrogen evolution reaction (HER) with the low Eonset (-39 mV vs. RHE), overpotential (56 mV vs. RHE) at the fixed current density of 10 mA cm-2, and small Tafel slope (39 mV dec-1). This is ascribed to the synergistic effects of the bimetals, rGO as the good support, and electronic coupling between the Pd shell and the Pt core.