<p>The exploration of suitable non-precious earth-abundant materials with sufficient active sites and their interaction with a suitable conducting support is very important for efficient water-splitting reactions to generate clean hydrogen fuel. The present study reports the in-situ growth of carbon supported cobalt sulfide (CoS) micro-structured crystals over graphite and copper sheets using a simple brush coated one-step calcinations technique and their electro-catalytic behavior towards oxygen evolution reaction (OER). Carbon supported powder CoS material was also synthesized under identical conditions in order to compare the performance with the material synthesized by in-situ technique. The electrochemical analysis demonstrates that the material grown in-situ over graphite/copper electrodes possesses better catalytic activities than the powder sample. The observed over-potential of the binder free self-supported film electrode for the oxygen evolution reaction (OER) was 270&#xa0;mV compared to&#xa0;413&#xa0;mV for the powder sample to achieve the current density of 10&#xa0;mA&#xa0;cm⁻²&#xa0;in 1&#xa0;M KOH solution. The synthesized carbon supported CoS materials were further characterized using various spectroscopic techniques, such as, XRD, FE-SEM, EDX and XPS. The long-term durability test of the carbon supported CoS/Gr material was conducted in alkaline medium to confirm its possible uses as a promising electrode material for the oxygen evolution reaction. The long-term stability over 16&#xa0;h&#xa0;of the carbon supported CoS/Gr material&#xa0;was explained in terms of strong interaction between the active material and the conducting support.</p> Graphical abstract <p>A study of interaction between binders free self supported CoS films and the conducting graphite sheet for electrochemical oxygen evolution reaction</p>