Hydrogen production using novel catalysts is regarded as one of the most needed technology for the future economic needs and water splitting to give H2 gas, which is a challenging task for large-scale production. This work reports the synthesis of Meso-Cu-BTC metal organic framework and further used for understanding its role in electrochemical hydrogen evolution reaction (HER) in 1 M NaOH solution. Meso-Cu-BTC electrocatalyst showed a less overpotential of 89.32 mV and an onset potential of 25 mV with an appreciable current density. Results show a low Tafel slope of 33.41 mVdec−1 and long-term durability. Thus, the overall results show that Meso-Cu-BTC acted as a good candidate for electrocatalysis towards hydrogen evolution.

The present study reports the synthesis of a porous Fe-based MOF named MIL-100(Fe) by a modified hydrothermal method without the HF process. The synthesis gave a high surface area with the specific surface area calculated to be 2551 m 2 g –1 and a pore volume of 1.407 cm 3 g –1 with an average pore size of 1.103 nm. The synthesized electrocatalyst having a high surface area is demonstrated as an excellent electrocatalyst for the hydrogen evolution reaction investigated in both acidic and alkaline media. As desired, the electrochemical results showed low Tafel slopes (53.59 and 56.65 mV dec –1 ), high exchange current densities (76.44 and 72.75 mA cm –2 ), low overpotentials (148.29 and 150.57 mV), and long-term stability in both media, respectively. The high activity is ascribed to the large surface area of the synthesized Fe-based metal–organic framework with porous nature.

A recent class of porous materials, viz., metal–organic frameworks (MOFs), finds applications in several areas. In this work, Cu-based MOFs (Cu–benzene-1,3,5-tricarboxylic acid) along with graphene oxide, viz., Cu-MOF/GO, are synthesized and used further for reducing CO 2 electrochemically. The reduction was accomplished in various supporting electrolytes, viz., KHCO 3 /H 2 O, tetrabutylammonium bromide (TBAB)/dimethylformamide (DMF), KBr/CH 3 OH, CH 3 COOK/CH 3 OH, TBAB/CH 3 OH, and tetrabutylammonium perchlorate (TBAP)/CH 3 OH to know their effect on product formation. The electrode fabricated with the synthesized material was used for testing the electroreduction of CO 2 at various polarization potentials. The electrochemical reduction of CO 2 is carried out via the polarization technique within the experimented potential regime vs saturated calomel electrode (SCE). Ion chromatography was employed for the analysis of the produced products in the electrolyte, and the results showed that HCOOH was the main product formed through reduction. The highest concentrations of HCOOH formed for different electrolytes are 0.1404 mM (−0.1 V), 66.57 mM (−0.6 V), 0.2690 mM (−0.5 V), 0.2390 mM (−0.5 V), 0.7784 mM (−0.4 V), and 0.3050 mM (−0.45 V) in various supporting electrolyte systems, viz., KHCO 3 /H 2 O, TBAB/DMF, KBr/CH 3 OH, CH 3 COOK/CH 3 OH, TBAB/CH 3 OH, and TBAP/CH 3 OH, respectively. The developed catalyst accomplished a significant efficiency in the conversion and reduction of CO 2 . A high faradic efficiency of 58% was obtained with 0.1 M TBAB/DMF electrolyte, whereas for Cu-MOF alone, the efficiency was 38%. Thus, the work is carried out using a cost-effective catalyst for the conversion of CO 2 to formic acid than using the commercial electrodes. The synergistic effect of GO sheets at 3 wt % concentration and Cu + OH – interaction leads to the formation of formic acid in various electrolytes.

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A wide variety of electrocatalysts has been evolved for hydrogen evolution reaction (HER) and it is reasonable to carry out HER with low cost electrocatalyst and a good efficiency. In this study, Cu3N was synthesized by nitridation of Cu2O and further utilized as an electrocatalyst towards HER. The developed Cu3N electrocatalyst was tested and results showed a low overpotential and moderate Tafel slope value (overpotential: 149.18 mV and Tafel slope 63.28 mV/dec at 10 mA/cm2) in alkaline medium with a charge transfer resistance value as calculated from electrochemical impendence spectroscopy being 1.44 Ω. Further from the experimental results, it was observed that the reaction kinetics was governed by Volmer–Heyrovsky mechanism. Moreover, Cu3N has shown an improved rate of electron transfer and enhanced accessible active sites, due to its structural properties and electrical conductivity. Thus the overall results show an excellent electrochemical performance, leading to a new pathway for the synthesis of low cost electrocatalyst for energy conversion and storage.