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The electrochemical conversion of N2 to NH3 using a polymeric electrolyte reactor is a promising method to accelerate the green production of hydrogen carriers. On this basis, we report the efficiency of ammonia production by the nitrogen reduction reaction using a Cu/C catalyst in a polymeric electrolyte membrane reactor. The Cu/C catalyst was prepared by the NaBH4 reduction method and characterized by X-ray diffraction, transmission electron microscopy, cyclic voltammetry, and conversion experiments performed in a polymer electrolyte membrane fuel cell type reactor. The X-ray diffraction results showed the presence of CuO2 and carbon phases, while the TEM images showed a high agglomeration of copper nanoparticles on carbon. The onset potential of nitrogen reduction was near to the Cu (I) to Cu0 reduction peak. Mass spectroscopy was used to observe the production of N2H2 and NH3 and the consumption of N2. Maximum ammonia production was detected at 0.0 V with a NH3 yield rate of 38.4 µg h−1 cm−2 and a faradaic efficiency of 42.57 %.

To enhance the contact between the electrolyte (source of O2−) and the carbon fuel in solid oxide–direct carbon fuel cells (SO-DCFCs), molten metals and molten salts were used in the anode chamber. Oxygen ions can dissolve and be transported in the molten medium to the anode three-phase boundary to reach and oxidize the carbon particles. To improve the sluggish kinetics of the electrochemical oxidation of carbon, the same molten media can act as redox mediators. Moreover, using a liquid metal/salt anode, tolerant to fuel impurities, the negative effect of carbon contaminants on cell performance is mitigated. In this work, an overview of SO-DCFCs with liquid metals, liquid carbonates, and mixed liquid metals/liquid carbonates in the anode chamber is presented and their performance was compared to that of conventional SO-DCFCs.

The conversion of methane into chemicals is of interest to achieve a decarbonized future. Fuel cells are electrochemical devices commonly used to obtain electrical energy but can be utilized either for chemicals’ production or both energy and chemicals cogeneration. In this work, the partial oxidation of methane in fuel cells for electricity generation and valuable chemicals production at the same time is reviewed. For this purpose, we compile different types of methane-fed fuel cells, both low- and high-temperature fuel cells. Despite the fact that few studies have been conducted on this subject, promising results are driving the development of fuel cells that use methane as a fuel source for the cogeneration of power and valuable chemicals.