Abstract
Activated carbon is one of the multi functional materials which promotes the electrochemical catalysis for hydrogen production in greener way. In the present work, the fruit shells of Tamarindus indica have been used to synthesize the carbon structure at different temperatures by chemical vapour deposition method. The structural confirmation has been done by XRD analysis which authenticates the crystalline nature of activated carbon with hexagonal crystal structure. XRD analysis revealed 2 peaks at 2 theta of 23 degrees-29 degrees indexed to (002) plane reflection (hexagonal crystallographic structure) and disclosed crystalline nature of activated carbon. From RAMAN spectroscopic technique, the appearance of D and G bands at ~1358 and ~1586 cm(-1) elucidates formation of graphitic phase of carbon. The ratio of I-D/I-G is found to be almost ~0.84, indicates low level of disorder and the graphitic nature of the samples. Morphological analysis has been done using SEM on the synthesized samples which reveals the presence of voids and cracks on the surface of the material and the size of the particle is about few micrometer. The synthesized material T-800 degrees C displays the low overpotential of 221 mV and 490 mV at 10 mA/cm(2) and 50 mA/cm(2) compared with that of T-700 degrees C (230 mV@10 mA/cm(2) and 546 mV@50 mA/cm(2)) and T-900 degrees C (269 mV@10 mA/cm(2) and 547 mV@50 mA/cm(2)). Electrochemical impedance study informs the solution resistance value of prepared samples are 1.91, 1.60 and 1.63 omega respectively. The sample T-800 degrees C exhibits low R-s indicates the improved conductivity, which enhances the catalytic activity in favor of HER. The fabricated electrode of T-800 degrees C exhibits excellent electrochemical properties and stability with the retention of 51.7 %.