A SBA-15-templated mesoporous NiFe2O4/MXene nanocomposite for the alkaline hydrogen evolution reaction

Abstract

The development of efficient and cost-effective electrocatalysts for the hydrogen evolution reaction (HER) is crucial for renewable energy conversion and storage. Here, we report the synthesis of a mesoporous NiFe₂O₄/MXene nanocomposite for the alkaline HER. The as-prepared nanocomposite demonstrated a synergistic effect in facilitating the HER, as evidenced by significantly improved electrocatalytic activity compared to individual NiFe₂O₄ and MXene components. The mesoporous structure of the nanocomposite, derived from the SBA-15 template, provided a large surface area and enhanced mass transport, while the incorporation of MXene as a conductive additive improved the charge transfer kinetics. Based on the results, the NiFe₂O₄/MXene nanocomposite exhibited a low onset overpotential of −440 mV, a small Tafel slope of 187.5 mV per decade, and long-term stability for the HER in alkaline electrolytes, as opposed to the individual NiFe₂O₄ or MXene. The enhanced electrocatalytic performance was attributed to the synergistic effect of the unique mesoporous structure, high conductivity, and abundant active sites provided by NiFe₂O₄ and MXene. However, DFT calculations revealed that more favorable H atom adsorption and activation processes were observed on the surface of the NiFe₂O₄ (400) plane. Our findings highlight the potential of using templated mesoporous nanocomposites for designing efficient electrocatalysts for the alkaline HER and contribute to the advancement of renewable energy technologies.