Two-dimensional materials have been extensively researched as catalysts for hydrogen generation over the past two decades due to their exceptional catalytic properties and unique atomic structure . This study investigated these compounds' hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activities, focusing on their suitable band gaps. It is wellknown that an attractive semiconductor for HER/OER must have band edges that align with the redox potentials of water. Specifically, the valence band maximum (VBM) should be more positive than the H 2 O/H 2 level. The conduction band minimum (CBM) should be more negative than the H 2 O/O 2 level, ensuring favourable water-splitting energetics without needing an applied bias voltage. To design an efficient photo-catalyst for watersplitting, it is crucial to determine the semiconductor's band edge positions relative to the H 2 O/O 2 and H 2 O/H 2 levels in water. A straightforward approach involves calculating these band edge positions relative to a standard reference, typically the vacuum level. The standard redox potentials of water are -4.44 eV for reduction H 2 O/H 2 and -5.67 eV for oxidation H 2 O/O 2 using the vacuum level as a reference. Thus, the positions of the valence and conduction bands relative to the vacuum potential of the respective sheets were determined using the equations E V BE/CBE = E V BM/CBM -E vacuum . In all three C 60 configurations studied, the Fermi energy (E f ermi ) is around -0.60 eV, leading to an overpotential of about 4.28 eV relative to the HER redox potential. Figure shows that by employing PBE functional, the HER potential lies within the bandgap, highlighting the ability of C 60 and C 54 B 3 N 3 sheets to reduce H + to H 2 , thus presenting new possibilities in electrocatalysis. Whereas results based on HSE functional demonstrate that all three systems can reduce H + to H 2 . HSE results also indicate that C 60 has the potential for Oxygen Evolution Reaction (OER) activity. Based on HSE calculation, these systems' valence and conduction band edges effectively straddle the HER redox potential, suggesting their potential as metal-free electrocatalysts. Overall, HSE functional calculations indicate that the electronic structures of these systems favour their HER activity. Given that BN-doped C 60 can potentially replace Pt-based electrocatalysts, careful manipulation of its bandgap through defect engineering (e.g., altering the BN arrangement) could lead to the development of efficient non-metal photo-and electro-catalysts for HER.