Facile construction of 3D hyperbranched PtRh nanoassemblies: A bifunctional electrocatalyst for hydrogen evolution and polyhydric alcohol oxidation reactions

Abstract Development of highly effective and stable electrocatalysts is urgent for various energy conversion applications. Herein, a facile co-reduction approach was developed to fabricate three-dimensional (3D) hyperbranched PtRh nanoassemblies (NAs) under solvothermal conditions, where creatinine and cetyltrimethylammonium chloride (CTAC) were employed as the structure-directing agents. The as-synthesized nanocatalyst exhibited intriguing catalytic characters for hydrogen evolution reduction (HER) with a low overpotential (20 mV) at 10 mA cm−2 and a small Tafel slope (49.01 mV dec−1). Meanwhile, the catalyst showed remarkably enlarged mass activity (MA: 2.16/2.02 A mg−1) and specific activity (SA: 4.16/3.88 mA cm−2) towards ethylene glycol and glycerol oxidation reactions (EGOR and GOR) alternative to commercial Pt black and homemade Pt3Rh nanodendrites (NDs), PtRh3 NDs and Pt nanoparticles (NPs). This method offers a feasible platform to fabricate bifunctional, efficient, durable and cost-effective nanocatalysts with finely engineered structures and morphologies for renewable energy devices.