Harnessing fluorine-driven synergistic interactions in Boron-MOF to achieve high-efficiency water splitting

Metal organic frameworks (MOFs) exhibit remarkable potential in electrocatalysis owing to their tunable structure and chemical versatility. In this work, we investigate the integration of heteroatoms—boron (B), nickel (Ni), and fluorine (F) into MOF-derived carbonaceous materials to tailor their electronic properties and enhance catalytic performance. We have synthesized fluorine- incorporated nickel-doped boron and nitrogen co-doped graphitic carbon nanosheets (F-Ni/BMOF- 670) along with a fluorine-free counterpart (Ni/BMOF-670) through direct thermal treatment of fluorine/nickel-containing boron imidazolate frameworks. The presence of fluorine promotes charge polarization around active sites and simultaneously stabilizes the carbon matrix, leading to improved surface characteristics and catalyst robustness. Electrochemical tests demonstrate that F-Ni/BMOF- 670 achieves excellent dual-function catalytic behavior, with overpotentials of approximately 90 mV for hydrogen evolution and 200 mV for oxygen evolution reactions. Furthermore, the catalyst exhibits a low overall water splitting cell voltage near 1.48 V and maintains exceptional stability with negligible loss over prolonged cycling. This study highlights the synergistic effects of multi- heteroatom doping from boron imidazolate frameworks, providing key insights into designing advanced, durable electrocatalysts for efficient water-splitting applications.