A novel NiFe-LDH/SnS layered electrocatalyst was synthesized using a hydrothermal method to enhance oxygen evolution reaction (OER) performance for water splitting. The incorporation of 2D SnS significantly improved the conductivity of NiFe-LDH sheets, reduced charge transfer resistance, and modulated the electronic environment around active sites, favoring intermediate adsorption during OER. Density functional theory (DFT) calculations showed that the NiFe-LDH/SnS heterostructure lowered energy barriers in key OER steps, enhancing reaction kinetics. The resulting catalyst exhibited a 20% and 27% reduction in overpotential and Tafel slope compared to pristine NiFe-LDH, respectively. The SnS-mediated NiFe-LDH composite demonstrated excellent electrocatalytic performance, with a low overpotential of 310 mV at 10 mA/cm² and a small Tafel slope of 53.6 mV/dec. The results highlight the effectiveness of SnS in regulating NiFe-LDH-based catalysts through structural, electronic, and energetic modulation, offering a strategy for designing efficient electrocatalysts for water splitting. The study also shows that SnS alone has limited OER activity, but when combined with NiFe-LDH, it enhances performance by optimizing active site environments and charge transfer. The NiFe-LDH/SnS heterostructure improves electrical conductivity, lowers reaction barriers, and enhances OER efficiency through synergistic effects in structural, electronic, and electrical properties. This work provides insights into the design of advanced 2D materials for electrocatalytic applications.A novel NiFe-LDH/SnS layered electrocatalyst was synthesized using a hydrothermal method to enhance oxygen evolution reaction (OER) performance for water splitting. The incorporation of 2D SnS significantly improved the conductivity of NiFe-LDH sheets, reduced charge transfer resistance, and modulated the electronic environment around active sites, favoring intermediate adsorption during OER. Density functional theory (DFT) calculations showed that the NiFe-LDH/SnS heterostructure lowered energy barriers in key OER steps, enhancing reaction kinetics. The resulting catalyst exhibited a 20% and 27% reduction in overpotential and Tafel slope compared to pristine NiFe-LDH, respectively. The SnS-mediated NiFe-LDH composite demonstrated excellent electrocatalytic performance, with a low overpotential of 310 mV at 10 mA/cm² and a small Tafel slope of 53.6 mV/dec. The results highlight the effectiveness of SnS in regulating NiFe-LDH-based catalysts through structural, electronic, and energetic modulation, offering a strategy for designing efficient electrocatalysts for water splitting. The study also shows that SnS alone has limited OER activity, but when combined with NiFe-LDH, it enhances performance by optimizing active site environments and charge transfer. The NiFe-LDH/SnS heterostructure improves electrical conductivity, lowers reaction barriers, and enhances OER efficiency through synergistic effects in structural, electronic, and electrical properties. This work provides insights into the design of advanced 2D materials for electrocatalytic applications.