Catalytic Reinforcement in Hybrid Imidazole Functionalized Cobalt Phthalocyanine and Ketjenblack for Boosted Hydrogen Evolution

Hydrogen energy is widely regarded as one of the cleanest forms of green energy due to its bio‐friendly nature.  One of the major issues is related to high production cost, which can be overcome by designing of effective catalysts . In this study, we report the synthesis of an eco‐friendly, affordable, and highly redox‐active tetra‐imidazole functionalized cobalt phthalocyanine (TImCoPc) through a straightforward method.  The electrocatalytic performance and conductivity of TImCoPc is further enhanced by forming hybrid with highly conductive Ketjenblack (KB) in various ratios. The 3.5:1.5 (TImCoPc/KB) composite exhibited excellent HER performance, with an onset potential closer to that of Pt/C and an overpotential (η10) of ‐108 mV, closely approaching the η­10 of Pt/C (‐36 mV). Additionally, the optimized hybrid showed a lower Tafel slope of 44 mV/dec, higher turnover frequency of 3.66 x 10‐10 mol s‐1 cm‐2 and mass activity of 4.121 A.mg‐1, with an excellent catalytic stability, thereby proving to be one of the superior electrocatalysts for HER in terms of cost, methodology, activity and efficiency. The observed enhancement in HER activity of the hybrid can be accounted to the synergistic effects that reduce the metal ion’s d‐band center and improve π‐π interactions between the hybrid components.