With increasing globalization and the urgent need for sustainable energy solutions, electrochemical water splitting has emerged as a crucial technology for clean energy production. In this study, we report the successful synthesis of 0.1 % Fe-doped NiS2 via a one-step hydrothermal method. The incorporation of Fe into the NiS2 matrix significantly enhances its electrochemical performance, as evidenced by a remarkable reduction in overpotential, to 180 mV at a current density of 10 mA cm-2, compared to 250 mV for undoped NiS2. Additionally, the Fe-doped NiS2 exhibits a reduced Tafel slope, high double layer capacitance, and lower charge transfer resistance than undoped NiS2, indicating improved reaction kinetics for oxygen evolution. These improvements are attributed to the enhanced conductivity and catalytic activity imparted by Fe doping, which facilitates more efficient charge transfer and reaction processes at the electrode surface. The results suggest that Fe-doped NiS2 is a highly promising and robust candidate for applications in electrochemical energy conversion. Moreover, the doping strategy employed here offers a valuable approach for tailoring the properties of other metal sulfides and chalcogenides, paving the way for the design of next generation electrocatalysts that can drive large-scale energy conversion processes with minimal energy loss.

Abstract
1. Introduction
2. Experimental Procedure
3. Results and Discussion
    3.1. Structural characterizations
    3.2. Electrochemical analysis
5. Conclusion and Prospects
Acknowledgement
References
Author Information

• Shoupik Mullani(Department of Intelligent Electronics and Computer Engineering, Chonnam National University, Gwangju 61186, Republic of Korea)
• Chihoon Kim(Department of Intelligent Electronics and Computer Engineering, Chonnam National University, Gwangju 61186, Republic of Korea)
• Shital Bachankar(Department of Intelligent Electronics and Computer Engineering, Chonnam National University, Gwangju 61186, Republic of Korea)
• Aditi Kumbhar(Department of Intelligent Electronics and Computer Engineering, Chonnam National University, Gwangju 61186, Republic of Korea)
• Taeksoo Ji(Department of Intelligent Electronics and Computer Engineering, Chonnam National University, Gwangju 61186, Republic of Korea) Corresponding author
• Vaibhav Lokhande(Global Innovative Centre for Advanced Nanomaterials, College of Engineering, Science and Environment, The University of Newcastle, Newcastle 2308, Australia)