Interface Catalysts of Ni₃Fe₁ Layered Double Hydroxide and Titanium Carbide for High-Performance Water Oxidation in Alkaline and Natural Conditions

Abstract

The electrocatalytic oxygen evolution reaction (OER) is important for many renewable energy technologies. Developing cost-effective electrocatalysts with high performance remains a great challenge. Here, we successfully demonstrate our novel interface catalyst comprised of Ni₃Fe₁-based layered double hydroxides (Ni₃Fe₁-LDH) vertically immobilized on a two-dimensional MXene (Ti₃C₂T_<i>x</i>) surface. The Ni₃Fe₁-LDH/Ti₃C₂T_<i>x</i> yielded an anodic OER current of 100 mA cm^-2 at 0.28 V versus reversible hydrogen electrode (RHE), nearly 74 times lower than that of the pristine Ni₃Fe₁-LDH. Furthermore, the Ni₃Fe₁-LDH/Ti₃C₂T_<i>x</i> catalyst requires an overpotential of only 0.31 V versus RHE to deliver an industrial-level current density as high as 1000 mA cm^-2. Such excellent OER activity was attributed to the synergistic interface effect between Ni₃Fe₁-LDH and Ti₃C₂T_<i>x</i>. Density functional theory (DFT) results further reveal that the Ti₃C₂T_<i>x</i> support can efficiently accelerate the electron extraction from Ni₃Fe₁-LDH and tailor the electronic structure of catalytic sites, resulting in enhanced OER performance.