Ammonia is an important precursor of fertilizers, as well as a potential carbon-free energy carrier. Nowadays, ammonia is synthesized via the Haber-Bosch process which is capital-and energyintensive process with an immense CO 2 footprint. Thus, alternative processes for the sustainable and decentralized ammonia production from N2 and H2O using renewable electricity are required.The key challenges for the realization of such processes are the efficient activation of the N2 bond and selectivity towards NH3. In this contribution, we report an all-electric method for sustainable ammonia production from nitrogen and water using a plasma-activated proton conducting solid oxide electrolyser. Hydrogen species produced by water oxidation over the anode are transported through the proton conducting membrane to the cathode where they react with the plasmaactivated nitrogen towards ammonia. Ammonia production rates and faradaic efficiencies up to of 26.8 nmol NH3/s/cm 2 and 88%, respectively, were achieved.H-B process, as they prevent the possibility of lowering capital costs [16], decentralization and small-scale ammonia production at the level of local communities. Moreover, the world's hydrogen, which is also a key reactant in ammonia production, is produced primarily from the steam reforming of methane, emitting huge amounts of CO2 that account for 1.6% of global emissions per year [2, 15]. Therefore, alternative technologies need to be explored for ammonia synthesis, which occur under more moderate conditions [17], require less carbon input [18], or can be powered by intermittent renewable energy sources [19].Nowadays, plasma technology has attracted a lot of attention as an alternative method of clean ammonia synthesis, including a renewable pathway that coupled this technology with other renewable energy approaches. At low temperature, plasmas are reported as one of the most efficient approaches for rupturing the triple nitrogen bond [20][21][22][23][24], which is the fundamental requirement for the ammonia synthesis. Most of the studies on plasma-assisted ammonia synthesis are based on atmospheric pressure dielectric barrier discharge plasma over various catalytic systems, with nitrogen conversion between 0.2-7.8% in N2/H2 mixtures [25][26][27][28][29][30]. There are also approaches in which plasma activation of nitrogen and water vapor (as a hydrogen source) have been investigated for ammonia synthesis offering promising results in terms of selectivity [31][32][33][34].However, there are a few studies on the synthesis of ammonia from nitrogen−hydrogen using low pressure (0.01−10 Torr) discharges [35][36][37][38][39][40]. In fact, low pressure nitrogen discharges are wellknown for efficiently producing vibrationally excited molecules that can further generate atomic nitrogen via a vibrational dissociation channel [41][42][43]. Despite the potential benefits of plasma technologies, such as localized and environmentally friendly energy storage through chemical conversion, the two most critical challenges for upscaling ...

With increasing global interest in renewable energy technology in the backdrop of climate change, storage of electrical energy has become particularly relevant. Most sustainable technologies (e.g. wind, solar) produce electricity intermittently. Thus, converting electrical energy and base molecules (i.e. H2O, N2) into energy rich ones (e.g. H2, NH3) or chemical feedstock (e.g. NO) is of paramount importance. While H2O splitting is compatible with renewable electricity, N2 fixation is currently dominated by thermally activated processes. In this work, we demonstrate an all-electric route for simultaneous NO and H2 production. In our approach, H2O is reduced to H2 in the cathode of a solid oxide electrolyser while NO is produced in the anode by the reaction of O 2species (transported via the electrolyte) and plasma activated N2 species. High faradaic

Solid oxide fuel cell–gas turbine (SOFC‐GT) systems provide a thermodynamically high efficiency alternative for power generation from biofuels. In this study biofuels namely methane, ethanol, methanol, hydrogen, and ammonia are evaluated exergetically with respect to their performance at system level and in system components like heat exchangers, fuel cell, gas turbine, combustor, compressor, and the stack. Further, the fuel cell losses are investigated in detail with respect to their dependence on operating parameters such as fuel utilization, Nernst voltage, etc. as well as fuel specific parameters like heat effects. It is found that the heat effects play a major role in setting up the flows in the system and hence, power levels attained in individual components. The per pass fuel utilization dictates the efficiency of the fuel cell itself, but the system efficiency is not entirely dependent on fuel cell efficiency alone, but depends on the split between the fuel cell and gas turbine powers which in turn depends highly on the nature of the fuel and its chemistry. Counter intuitively it is found that with recycle, the fuel cell efficiency of methane is less than that of hydrogen but the system efficiency of methane is higher.

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