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A Study on Electrochemical Ammonia Synthesis with Proton-Conducting Solid Oxide Electrolytic Cells
Presentation

A Study on Electrochemical Ammonia Synthesis with Proton-Conducting Solid Oxide Electrolytic Cells

Kangyong LeeSeungJin JeongWooChul JungJoongmyeon BaeSai P. Katikaneni

Ammonia has become one of the most important chemicals with its versatility since the Haber-Bosch process was invented. Recently, ammonia has been getting interests because of its possibility as a hydrogen carrier. Since ammonia has high energy density and carbon-free characteristics, using ammonia as a fuel of solid oxide fuel cells is advantageous. However, the Haber-Bosch process spends much electricity because of the high pressure condition, and the process consumes more than 1% of energy consumption worldwide. Therefore, the development of a new method for the ammonia production is necessary. In this study, solid oxide based electrolytic cells were fabricated…

Electrochemical Reduction of Nitrogen to Ammonia over Transition Metals
Presentation

Electrochemical Reduction of Nitrogen to Ammonia over Transition Metals

Victoria SmithAditya PrajapatiMeenesh R. Singh

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…

New Insights into Electrocatalysis of Nitrogen Reduction to Ammonia
Presentation

New Insights into Electrocatalysis of Nitrogen Reduction to Ammonia

Alex SchechterRevanasiddappa Manjunatha

Ammonia was electrochemically produced from nitrogen and water using a ruthenium–platinum (RuPt) alloy catalyst cathode and a nickel anode at ambient pressure and room temperature. The rate of ammonia formation was 5.1 × 10−9 gNH3 s−1 cm−2 with a 13.2% faradaic efficiency at an applied potential of 0.123 V vs. RHE; it reached 1.08 × 10−8 gNH3 s−1 cm−2 at 0.023 V. Ammonia production was investigated under selected potentials and temperatures. Real-time direct electrochemical mass spectrometric (DEMS) analysis of the evolved gases was performed at various applied potentials. In general, the mass-to-charge ratio signals of hydrogen and ammonia were detected,…

Enhanced Electrochemical Ammonia Production Via Peptide-Bound Metal
Presentation

Enhanced Electrochemical Ammonia Production Via Peptide-Bound Metal

Charles LoneyJulie RennerDavid SuttmillerLauren F. GreenleeMichael Janik

Approximately half of the people on the planet are alive because of synthetically produced ammonia. However, due to the fossil fuels used in the current ammonia synthesis process, its production contributes a significant amount to the world’s greenhouse gas emissions. Haber-Bosch synthesis, which is the most widely used method of producing synthetic ammonia today, requires high temperatures (400-500 °C) and pressures (150-200 atm). This process is also energy intensive, consuming approximately 2% of worldwide energy. By taking an electrochemically-based approach to ammonia synthesis, those harsh conditions and emissions can be eliminated. However, current catalysts are not selective for the desired…

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

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

Sharad MaheshwariYawei LiMichael JanikGholamreza RostamikiaLauren F. GreenleeJulie Renner

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…

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

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

Xuan YangJared NashJacob AnibalMarco DunwellYushan YanBingjun Xu

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…

Electrochemical Synthesis of Ammonia Using Metal Nitride Catalsyts
Presentation

Electrochemical Synthesis of Ammonia Using Metal Nitride Catalsyts

Jared NashXuan YangJacob AnibalYushan YanBingjun Xu

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…

Highly-Selective Electrochemical Reduction of Dinitrogen to Ammonia at Ambient Temperature and Pressure
Presentation

Highly-Selective Electrochemical Reduction of Dinitrogen to Ammonia at Ambient Temperature and Pressure

Qiang ZhangXiaoyang CuiCheng Tang

Catalytic conversion of dinitrogen (N2) into ammonia under ambient conditions represents one of the Holy Grails in catalysis and surface science. As a potential alternative to the Haber-Bosch process, electrochemical reduction of N2 to NH3 is attractive owing to its renewability and flexibility, as well as sustainability for producing and storing value-added chemicals from the abundant feedstock of water and nitrogen on earth. However, owing to the kinetically complex and energetically challenging N2 reduction reaction (NRR) process, NRR electrocatalysts with high catalytic activity and high selectivity are rare. In this contribution, as a proof-of-concept, we demonstrate that both the NH3…

Identifying the Prospects of Electrochemical Ammonia Synthesis on Mxenes Using First Principles Calculations
Presentation

Identifying the Prospects of Electrochemical Ammonia Synthesis on Mxenes Using First Principles Calculations

Gurjyot SethiVenkatasubramanian Viswanathan

Electrochemical synthesis of ammonia is a major challenge aimed at making production of ammonia sustainable. Currently ruthenium is the transition metal of choice for catalyzing the industrial Haber-Bosch process. However, electrochemical ammonia synthesis on ruthenium suffers from high overpotential and the competing hydrogen evolution reaction. Recently layered transition metals carbides and nitrides (MXenes) have been identified as a potential material class for ammonia synthesis. MXenes are particularly interesting owing to the high degree of tunability in surface chemistry due to the transition metal choice, interlayer distance, number of layers in the material, and surface termination. These choices affect the electron…

A Low Pressure Membrane Based Renewable Ammonia Synthesis
Presentation

A Low Pressure Membrane Based Renewable Ammonia Synthesis

Sarbjit Giddey

Ammonia is currently mostly produced by the highly energy and carbon-intensive Haber–Bosch process, which requires temperatures of 450–500 °C and pressures of up to 200 bar. The feedstock for this process is hydrogen from natural gas (NG), coal or oil, and nitrogen produced from air by cryogenic route or pressure swing adsorption (PSA). The share of NG, coal and fuel oil feedstock for the global production of ammonia is 72%, 22% and 4% respectively, contributing to approximately 420 million tons of CO2 emissions per annum, representing over 1% of global energy related emissions. The energy consumed for ammonia synthesis by…