Modulating the Electronic Structure of Porous Nanocubes Derived from Trimetallic Metal–Organic Frameworks to Boost Oxygen Evolution Reaction Performance

The preparation of noble metal‐free catalysts for water splitting is the key to low‐cost, sustainable hydrogen generation. Herein, through a pyrolysis‐oxidation process, we prepared a series of Co‐Fe‐Ni trimetallic oxidized carbon nanocubes (Co_1‐XFe_XNi‐OCNC) with a continuously changeable Co/Fe ratio (X=0, 0.1, 0.2, 0.5, 0.8, 0.9, 1). The Co_1‐XFe_XNi‐OCNC shows a volcano‐type oxygen evolution reaction (OER) activity. The optimized Co_0.1Fe_0.9Ni‐OCNC achieves a low overpotential of 268 mV at 10 mA cm^?2 with a very low Tafel slope of 48 mV dec^?1 in 1 m KOH. At the same time, the stability of the Co_0.1Fe_0.9Ni‐OCNC is also outstanding; after 1000 CV cycles, the LSV plot is almost coincident. Moreover, the potential remains almost of the same value at 10 mA cm^?2 after 12 h in comparison to the initial value. The excellent electrocatalytic properties can be attributed to the synergistic cooperation between each component. Therefore, the Co_0.1Fe_0.9Ni‐OCNC is a promising candidate instead of precious metal‐based electrocatalysts for OER.