Hydrogen evolution reaction (HER) on Pt and Pd is well investigated and widely reported in the literature [1]. Because of the widespread use of electrolysis, precious metal content in the electrolyzer needs to be reduced or replaced by alternative electrocatalysts. MoS2, among all other catalysts, shows a promising electrocatalytic activity towards HER due to its layered structure and exposed active edges [2].The hexagonal layered structure of MoS2, generally known as the 2H phase, is semiconducting in nature. Based on the synthesis conditions, n-type or p-type MoS2 can be synthesized by controlling the surface defects or vacancies [3]. Depending on the semiconductor characteristics (n or p), MoS2 shows photo sensitivity thereby catalyzing various electrochemical reactions.Layered molybdenum disulfide (MoS2) is synthesized by the conventional hydrothermal method at 220 °C [4]. The vacancies or surface defects are controlled to synthesize n-type or p type MoS2. Mott-Schottky analysis confirms different types of conductivity in prepared samples. HER activity of the catalysts is measured in Ar-saturated 0.5 (M) H2SO4. The kinetic parameters (exchange current density and rate constant) towards HER on MoS2 are estimated using electrochemical impedance spectroscopy [5]. Faster kinetics is observed in case of p-type MoS2, though HER is a cathodic reaction. This fast kinetics suggests its higher electrode-electrolyte interaction, i.e., higher wettability. References R. K. Singh, R. Ramesh, R. Devivaraprasad, A. Chakraborty and M. Neergat, Electrochim. Acta, 2016, 194, 199–210.J. D. Benck, T. R. Hellstern, J. Kibsgaard, P. Chakthranont, and T. F. Jaramillo, ACS Catal. 2014, 4, 3957–3971.J. Heising and M. G. Kanatzidis, J. Am. Chem. Soc., 1999, 121, 11720–11732.M. Li, D. Wang, J. Li, Z. Pan, H. Ma, Y. Jiang and Z. Tiang, RSC Adv., 2016, 6, 71534–71542.R. K. Singh, R. Devivaraprasad, T. Kar, A. Chakraborty and M. Neergat, J. Electrochem. Soc., 2015, 162(6), F489-F498. Figure 1