Interfacial Strain-Modulated Nanospherical Ni2 P by Heteronuclei-Mediated Growth on Ti3 C2 Tx MXene for Efficient Hydrogen Evolution.

Abstract

Interface modulation of nickel phosphide (Ni2 P) to produce an optimal catalytic activation barrier has been considered a promising approach to enhance the hydrogen production activity via water splitting. Herein, heteronuclei-mediated in situ growth of hollow Ni2 P nanospheres on a surface defect-engineered titanium carbide (Ti3 C2 Tx ) MXene showing high electrochemical activity for the hydrogen evolution reaction (HER) is demonstrated. The heteronucleation drives intrinsic strain in hexagonal Ni2 P with an observable distortion at the Ni2 P@Ti3 C2 Tx MXene heterointerface, which leads to charge redistribution and improved charge transfer at the interface between the two components. The strain at the Ni2 P@Ti3 C2 Tx MXene heterointerface significantly boosts the electrochemical catalytic activities and stability toward HER in an acidic medium via a combination between experimental results and theoretical calculations. In a 0.5m H2 SO4 electrolyte, the Ni2 P@Ti3 C2 Tx MXene hybrid shows excellent HER catalytic performance, requiring an overpotential of 123.6mV to achieve 10mA cm-2 with a Tafel slope of 39mV dec-1 and impressive durability over 24h operation. This approach presents a significant potential to rationally design advanced catalysts coupled with 2D materials and transition metal-based compounds for state-of-the-art high efficiency energy conversions.