Interfacial Covalent Bonds Between Fe-MoS₂ Quantum Dots and CoFe-MOF Triggering the Strain Effect for Efficient...

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-MoS₂ 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 H₂O/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 F₁MQ/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.