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In Situ Growth of Nitrogen-Doped Carbon Coated γ-Fe; O; Nanoparticles on Carbon Fabric for Electrochemical N; Fixation

Nitrogen fixation to ammonia (NH3) has attracted intensive attention because NH3 is the critical inorganic fertilizers and energy carrier. Haber-Bosch process, the industrial procedure for NH3 production, is confined to the extreme condition requirements. Hence, it is highly desirable to develop a renewable and environment-friendly route for nitrogen fixation to replace the conventional technology. Electrochemical nitrogen reduction reaction (NRR) is one of the most promising techniques since the electrical energy could be produced by synergy with the fast-growing renewable energy. However, electrochemical NRR approach faces huge challenge in breaking extremely high N≡N bond energy (940.95 kJ mol–1) in dinitrogen molecules.…

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Electrochemical Reduction of Dinitrogen to Ammonia Using Different Morphologies of Copper As Electro Catalysts

Ammonia is an effective hydrogen storage medium due to ease of transport as liquid, high storage capacity (17.65%) and it can easily be converted to hydrogen by electro-chemical oxidation. Haber-Bosch process is used for the synthesis of ammonia which is energy intensive as it requires high temperature and pressure. It also causes intense carbon emissions as the hydrogen is produced by steam reforming. Alternatively, ammonia can be synthesized electrochemically at ambient conditions from nitrogen and water by employing renewable energy in the presence of an electro catalyst. The major challenge in electrochemical synthesis of ammonia is low Faradaic efficiency. This…

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Electrochemical Promotion of Ammonia Synthesis with Proton-Conducting Ceramic Fuel Cells -Function of Electrode Interface for Ammonia Formation Reaction-

The advance of efficient and economical energy carrier technology is an important challenge in terms of storage and transport of hydrogen fuels produced from renewable energy. Ammonia is a promising candidate of energy carrier because of high energy density and easy liquefaction as well as a carbon-free fuel.1 Electrochemical synthesis has a potential for an efficient ammonia production in comparison with the industrial Haber–Bosch process. In our previous study, we observed the improvement of electrochemical synthesis of ammonia using iron-based electrode catalyst such as K-Al-Fe-BaCe0.9Y0.1O3 (BCY).2 In the study, basically, H2 decomposition occurs to form protons in the anode side,…

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New Technology of the Ammonia Co-Firing with Pulverized Coal to Reduce the NOx Emission

Ammonia is recognized as the new energy carrier and it is expected to be introduced into the society in a short time, since the infrastructures related to the ammonia, such as the mass production, transportation and storage are already introduced to produce the fertilizer for the agriculture. There is one technical issue, to use the ammonia in the direct combustion as the fuel for the electric power generation. It is the increase of the NO concentration in the exhaust gas. Ammonia contains the large amount of the nitrogen, comparing with any other fuels that human being has ever treated. Nitrogen…

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Atmonia: Sustainable Ammonia Production Using Electrocatalysis at Ambient Temperature and Pressure

Density functional theory simulations have shed light on reaction mechanisms, rate limiting steps and minimum energy paths for reactions to occur, in vacuum as well as in various media. Using that, we have selected certain criteria and revealed a few metal nitride surfaces that should be efficient and selective catalysts for nitrogen reduction in water. Recently, experimental confirmation was acquired for one of the surfaces. A novel methodology was developed where electrochemical catalysis chamber was directly connected in-line with a flow injection analysis method, providing direct detection of reaction rate and catalyst current efficiency, which is then further confirmed with…

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Electrochemical Synthesis of Ammonia Using Metal Nitride Catalsyts

With the development of the Haber process and the subsequent work done by Bosch, ammonia production become an industrially and economically viable way to fix nitrogen. This helped increase the global population and estimates put it at about 40% of the global population’s food comes from ammonia made by the Haber-Bosch process[1]. However, the Haber-Bosch process is an energy intensive process requiring high pressure (15-30 MPa) and relatively high temperature (430 °C – 480 °C) and is highly centralized with only about 13 companies and about 29 plants[2,3]. Renewable energy resources offer a possible alternative way to fix nitrogen at…

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Electrochemical Nitrogen Reduction Reaction on Transition Metal Nitride Nanoparticles in Proton Exchange Membrane Electrolyzers

Transition metal nitride nanoparticles are synthesized and utilized as catalysts for electrochemical nitrogen reduction reaction (ENRR) to produce ammonia in a proton exchange membrane electrolyzer (PEMEL). The catalysts show an average ENRR rate and Faradaic efficiency (FE) of 3.3 × 10−10 mol s−1 cm−2 (6.6 × 10−10 mol s−1 mg−1) and 5.95% at −0.1 V within 1 h, respectively. Both the ENRR rate and FE are approximately two orders of magnitude higher than those of noble metal catalysts. Time-dependent results suggest that the catalytic activity of transition metal nitride nanoparticles is stable at −0.1 V, with the catalytic activity decreasing…

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Low-Pressure Electrolytic Ammonia Synthesis Via High-Temperature Polymer-Based Proton Exchange Membrane

The University of North Dakota Energy and Environmental Research Center (EERC) and North Dakota State University (NDSU) have developed a low-pressure electrolytic ammonia (LPEA) production process. The LPEA process uses an electrochemical cell based on an innovative polymer–inorganic composite (PIC) high-temperature (300°C) gas-impermeable proton-exchange membrane conceptualized and partially developed by EERC and NDSU. Because of its operability at ambient pressure and quick start-up capability (versus traditional high-pressure Haber Bosch-based plants), the LPEA process offers compatibility with smaller-scale plants and intermittent operation, and a cost-effective means of monetizing (and storing) renewable energy as ammonia. EERC, NDSU, and Proton OnSite are embarking…

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Electrochemical Reduction of Nitrogen to Ammonia over Transition Metals

The ability to produce ammonia in a sustainable and efficient manner has been a topic of scientific and industrial importance for many years. The Haber-Bosch process has acted as the primary process for transforming nitrogen and hydrogen gas into ammonia. This process has become unsustainable in the foreseeable future and requires a cost-effective alternative. Ammonia is a critical component of fertilizer that is vital to the agriculture industry. The electrochemical reduction of N2 to ammonia would eliminate carbon dioxide emissions that are present in current ammonia production processes and allow for a environmentally favorable process. Although the electrochemical reduction of…

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DFT Analysis of Elementary N2 Electro-Reduction Kinetics on Transition Metal Surfaces

Ammonia is currently produced through the catalytic Haber Bosch process (HB) at temperatures of about 300 to 500 °C and pressure of about 200-300 atm. In a future with plentiful renewable electricity from distributed sources, an electro-chemical system to produce ammonia could efficiently generate ammonia on site and on demand. Possible heterogeneous catalysts for electro-chemical nitrogen reduction are currently marred by the poor rate and selectivity due to difficulty in activating the strong N-N bond and to the competing hydrogen evolution reaction (HER), resulting in infeasible faradaic efficiency. To develop more selective and active catalysts, better understanding of the mechanistic…