Interfacial Covalent Bonds Between Fe‐MoS ₂ Quantum Dots and CoFe‐MOF Triggering the Strain Effect for Efficient Overall Water Splitting

ABSTRACT The zero‐dimensional (0D)/two‐dimensional (2D) heterostructure offers a promising platform for exposing more active and accelerating electron transfer and reaction kinetics. However, conventional 0D/2D structure rely on van der Waals interactions suffered from week interfacial interaction, which compromises their intrinsic activity. Herein, a superhydrophilic Fe‐MoS ₂ quantum dot (FMQ) anchored on 2D CoFe‐MOF nanosheets is constructed to form 0D/2D heterointerface. The incorporation of FMQ not only mitigates nanosheet aggregation via steric hindrance, but also promotes mass transfer and enhances the accessibility of active sites for H ₂ O/OH ⁻ adsorption. The covalent interface formed between FMQ and CoFe‐MOF ensures structural stability and facilitates rapid electron transport. Furthermore, Fe doping introduces controllable lattice distortion, thus modulating the d‐band center of the metal sites. The optimized F ₁ MQ/CoFe‐MOF exhibits outstanding performance, requiring low overpotentials of 236 mV for OER and 183 mV for HER at 10 mA cm ⁻² in 1.0 m KOH, and demonstrates stable overall water splitting for over 120 h. This work paves a way to regulate electronic structures of 0D/2D heterostructures for the design of efficient electrocatalysts.