Recently, two-dimensional materials have gained increasing research attention due to their large surface area, high physical and chemical stability, and excellent electrocatalytic performances. Herein, we reported a simple and fast one-pot aqueous method for synthesis of two-dimensional porous bimetallic PtPd alloyed nanosheets (NSs) using benzyldimethylhexadecylammonium chloride (HDBAC) as the capping agent and stabilizer. The formation mechanism involved the oriented attachment and self-assembly. The PtPd NSs exhibited excellent oxygen reduction reaction (ORR) activity with the positive shift (ca. 43 mV) of the half-wave potential in 0.1 M KOH solution, clearly outperforming that of commercial Pt/C (50 wt%). Moreover, the as-prepared catalyst displayed 2.4 times enlargement in mass activity (MA, 382.10 mA mg(-1)) and 3.5 times enhancement in specific activity (SA, 0.95 mA cm(-2)) relative to those of Pt/C at 0.80 V. Meanwhile, the as-obtained catalyst demonstrated highly boosted hydrogen evolution reaction (HER) in 0.5 M H2SO4 electrolyte, surpassing that of Pt/C. These results reveal the practical applications of the catalyst in energy storage and conversion. (C) 2019 Elsevier Inc. All rights reserved.