The role of composition and porosity of MOF derived Cu-embedded carbon electrocatalyst for oxygen evolution reaction

Oxygen evolution reaction (OER) plays a vital role in the field of water splitting, which has a promising way of achieving high efficiency and clean energy. However, a large overpotential and sluggish kinetics limit the water splitting efficiency. Thus, development of effective electrocatalyst is a key point to make OER more practicable. In this communication, we account a metal–organic framework (MOF) pyrolization path for derived Cu-embedded porous carbon materials as electrocatalyst for efficient and superior OER application in an alkaline condition. The prominent effect of pyrolysis was observed on the porosity as well as Cu content which predominates its electrocatalytic properties. The rise in pyrolysis temperature decreases surface area (SSA) due to more contribution of macroporosity. The hybrid Cu₂O/Cu connected porous carbon form of the CuBTC C600 provides large channels for rapid electron transfer and beneficial for electrolyte penetration which enhances the catalytic property results in to a low overpotential of 310 mV @10 mA/cm² and Tafel slope (80 mV dec⁻¹), and exceptional long-term stability as compared to CuBTC and rest materials. The role of porosity and consortium effect of Cu NPs and Cu₂O along with effect of pyrolysis was studied and discussed.

Comparative LSV curves of CuBTC and its derived electrocatalyst, recorded in 1.0 M KOH at a scan rate of 10 mV/s.