Ultra‐Durability and Enhanced Activity of Amorphous Cobalt Anchored Polyaniline Synergistic towards Electrocatalytic Water Oxidation
Sundarraj Sriram, Selvam Mathi, Bakthavachalam Vishnu, B. Karthikeyan, Jayaraman Jayabharathi
Abstract
Abstract Cobalt anchored polyaniline electrocatalysts (Co@PANI) have been synthesized (Co@PANI‐200, Co@PANI‐400, Co@PANI‐600, Co@PANI‐800) and characterised. The electrical conductivity and stability of Co@PANI increased due to the synergistic effect of PANI and cobalt content. PANI prevents aggregation and show strong binding with cobalt ions. The Co@PANI‐600/GC shows low overpotential of 341 mV @ 10 mA cm −2 current density and the Tafel slope of Co@PANI‐600 (39 mV dec −1 ) was smaller than IrO 2 (98 mV dec −1 ) for OER. The calculated turnover frequency (TOF) of Co@PANI‐600/GC (0.01609 s −1 ) was ≈8 times higher than IrO2 (0.0014 s −1 ) at 1.60 V. Furthermore, the Co@PANI‐600/NF electrocatalyst shows an incredibly low overpotential of 251 mV @10 mA cm −2 . This new born Co@PANI‐600/NF exhibits durability over 250 h with only 5.1 % potential loss in alkaline medium. Co@PANI‐600 catalyst exhibits excellent OER performances as well as having enough kinetics to solve the sluggish rate of water oxidation. At 1.54 V, the solar driven water electrolysis demonstration supports the efficiency of new born electrocatalyst in solar to hydrogen conversion. These research findings confirm that Co@PANI‐600 can be used for large‐scale hydrogen generation at the lowest possible cost.