Engineering ultrafine PtIr alloy nanoparticles into porous nanobowls via a reactive template-engaged assembly strategy for high-performance electrocatalytic hydrogen production

Abstract

The delicate maneuver of geometric arrangement, overall nano-architecture and chemical component of noble metal-based electrocatalysts is greatly imperative for the advancement of various industrial technologies; however, it remains severely challenging. Herein, we demonstrate a functional amino-induced self-sacrificial templated strategy for the synthesis of hollow and porous platinum-iridium alloyed nanobowls (referred to as Pt₇Ir NBs hereafter) with asymmetric open shells composed of ultrafine nanoparticles. Owing to the PtIr bimetallic alloy synergy, small size of primary building blocks, and highly open structure, the self-supported Pt₇Ir NBs display a modulated electronic structure, 3D availability of exterior/interior surfaces, and high atom-utilization efficiency, which collectively make the resulting Pt₇Ir NBs competent high-performance electrocatalyst. As a demonstration, when electro-catalyzing the hydrogen evolution reaction (HER), the standard Pt₇Ir NBs with modicum Ir introduction deliver extraordinary electrocatalytic performance with an overpotential of 20 mV at 10 mA cm⁻² and remarkable long-term robustness in a 0.5 M H₂SO₄ electrolyte, exhibiting enormous potential for electrochemical H₂ production and various sustainable energy technologies. The innovative engineering of the nano-architecture of precious metal-based nanocrystals into well-defined porous and hollow structures via a feasible self-templated synthetic methodology may pave the way for the future development of a variety of high-efficiency electrocatalysts.