Speaker
Description
Transition metal dichalcogenides (TMDs), such as Tungsten disulfide (WS2) is a promising alternative non-noble metal catalysts to drive the electrocatalytic hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). However, their electrocatalytic performance is critically limited by the low density of active sites as well as their low electrical conductivity in a pristine form. Here we synthesized the time dependent WS2 by a simple hydrothermal technique for improved HER and OER activity. The synthesized WS2 at 200 °C for 24 hrs exhibits a low overpotential of -0.20 V at -10 mA cm-2 and 1.42 V at 10 mA cm-2 with low Tafel slopes of 92 mV dec-1 and 112 mV dec-1 for HER and OER, respectively. The enhanced HER and OER performance are ascribed to increased electrochemical active surface area and minimized impedance compared to precursor WS2. Therefore, this work emphasizes the many advantages implemented by designing highly active, durable, and cost-effective catalytic activity for a wide range of electrocatalytic applications.
Keywords: Tungsten disulfide; electrocatalysts; hydrogen evolution reaction; oxygen evolution reaction.
*Corresponding author: outron@gmail.com (H.K. Jeong), Tel: +82-53-850-6438, Fax: +82-53-850-6479.
