Synergistic interactions of H2 and N2 with molten gallium in the presence of plasma

Carreon, Maria L.; Jaramillo-Cabanzo, Daniel Felipe; Chaudhuri, I.; Menon, Madhu; Sunkara, Mahendra

doi:10.1116/1.5004540

Cited by 12 publications

(30 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These yields are 1.5‐2 times larger than for previously reported metals. Also notably, we improved the energy yields by two orders of magnitude compared to previous reports on ammonia synthesis in sub‐atmospheric plasmas . This was achieved through the preliminary understanding of the synergism occurring between molten metals and nitrogen and hydrogen plasmas .…”

Section: Resultsmentioning

confidence: 82%

“…H recombination to form H 2(g) can also contribute to a decrease in concentration H α . While some H recombination happens in the gas phase, most recombination involves the catalyst …”

Section: Resultsmentioning

confidence: 99%

“…Also notably, we improved the energy yields by two orders of magnitude compared to previous reports on ammonia synthesis in sub-atmospheric plasmas. [15,22,30,[32][33] This was achieved through the preliminary understanding of the synergism occurring between molten metals and nitrogen and hydrogen plasmas. [33] In a previous study by Carreon et al, [33] it was established that molten metals behave differently in plasma.…”

Section: Catalytic Activity On Pure Metal Catalysts: Plasma Catalysismentioning

confidence: 99%

“…[15,22,30,[32][33] This was achieved through the preliminary understanding of the synergism occurring between molten metals and nitrogen and hydrogen plasmas. [33] In a previous study by Carreon et al, [33] it was established that molten metals behave differently in plasma. They have the advantage of adsorbing higher amounts of excited species (performed in a plasma reactor as a batch process by measuring ΔP).…”

Section: Catalytic Activity On Pure Metal Catalysts: Plasma Catalysismentioning

confidence: 99%

“…While some H recombination happens in the gas phase, most recombination involves the catalyst. [33][34]…”

Section: Catalytic Activity On Pure Metal Catalysts: Plasma Catalysismentioning

confidence: 99%

See 4 more Smart Citations

Enhancement of the Yield of Ammonia by Hydrogen‐Sink Effect during Plasma Catalysis

et al. 2019

Self Cite

View full text Add to dashboard Cite

Plasma‐catalytic ammonia synthesis has been known since the early 1900s, but only until now efforts to optimize catalysts for this purpose are emerging. Here, we investigate various transition metals, low‐melting‐point metals, and gallium‐rich alloy catalysts for their activity towards ammonia production under a plasma environment. The best three pure metal catalysts were Ni, Sn and Au, which are not traditional catalysts for the current industrial ammonia synthesis. The ammonia yields for these catalysts were 34 %, 29 %, and 19 %, respectively. Synergistic effects were detected when employing alloys, as some alloys presented ∼25–50 % higher yields than their constituent metals. The employed metals were classified into two categories. Category I metals (Cu, Ag, Au and Fe), which are nitrophobic (excluding Fe, the Haber‐Bosch catalyst) and poor hydrogen sinks. For these metals, the measured concentration of Hα in the gas phase tended to correlate inversely with ammonia yield and directly with the H binding strength on the catalyst surface. Category II metals (Ga, In, Sn and Ni), which are good hydrogen sinks, tend to have a lower concentration of Hα in the gas phase than that of category I metals, which is consistent with their expected sink behavior. For these metals, the concentration of Hα correlates with ammonia yield. Plasma characterization experiments and DFT calculations suggest that the higher performance of Ni and Sn is related to the benefit of dissolving hydrogen to slow down H recombination, which is a feature that could be potentially optimized in future studies by rationally altering the catalyst composition.

show abstract

Section: Resultsmentioning

confidence: 82%

“…H recombination to form H 2(g) can also contribute to a decrease in concentration H α . While some H recombination happens in the gas phase, most recombination involves the catalyst …”

Section: Resultsmentioning

confidence: 99%

Section: Catalytic Activity On Pure Metal Catalysts: Plasma Catalysismentioning

confidence: 99%

Section: Catalytic Activity On Pure Metal Catalysts: Plasma Catalysismentioning

confidence: 99%

“…While some H recombination happens in the gas phase, most recombination involves the catalyst. [33][34]…”

Section: Catalytic Activity On Pure Metal Catalysts: Plasma Catalysismentioning

confidence: 99%

See 3 more Smart Citations

Enhancement of the Yield of Ammonia by Hydrogen‐Sink Effect during Plasma Catalysis

et al. 2019

Self Cite

View full text Add to dashboard Cite

show abstract

Review of low-temperature plasma nitrogen fixation technology

Chen

Yuan

et al. 2021

Waste Dispos. Sustain. Energy

View full text Add to dashboard Cite

Nitrogen fixation is essential for all forms of life, as nitrogen is required to biosynthesize fundamental building blocks of creatures, plants, and other life forms. As the main method of artificial nitrogen fixation, Haber–Bosch process (ammonia synthesis) has been supporting the agriculture and chemical industries since the 1910s. However, the disadvantages inherent to the Haber–Bosch process, such as high energy consumption and high emissions, cannot be ignored. Therefore, developing a green nitrogen fixation process has always been a research hotspot. Among the various technologies, plasma-assisted nitrogen fixation technology is very promising due to its small scale, mild reaction conditions, and flexible parameters. In the present work, the basic principles of plasma nitrogen fixation technology and its associated research progress are reviewed. The production efficiency of various plasmas is summarized and compared. Eventually, the prospect of nitrogen fixation using low-temperature plasma in the future was proposed.

show abstract

Liquid Phase Epitaxy of Gallium Nitride

Jaramillo-Cabanzo

Jasiński

Sunkara

2019

Crystal Growth & Design

Self Cite

View full text Add to dashboard Cite

In this work, liquid phase epitaxy of gallium nitride (GaN) has been achieved using pulsed plasma nitridation of molten Ga films. Typically, continuous exposure of Ga to nitrogen plasma results in the formation of a thick GaN crust that prevents the growth of GaN layers on GaN seeds or GaN-on-sapphire substrates. The GaN crust formation on molten Ga is a consequence of a high concentration of dissolved nitrogen at the top surface of molten Ga layers. Here, we present the concept of using pulse (on/off) sequences to control the concentration of nitrogen inside the melt and enable the growth of GaN at the molten Ga−substrate interface. Results showed that the technique allows for epitaxial growth on homosubstrates and promotes the growth of additional layers on the pre-existing seeds. High-resolution transmission electron microscopy characterization confirmed epitaxial growth of GaN. A mass transport model was developed to discuss the effect of bulk recombination, diffusion, and pulsing on the concentration of nitrogen into the molten Ga. Results indicated that pulsing favored both the recombination of radicals in the bulk and the diffusion of species into the metal compared to the dissolution of radicals. As a result, the concentration of nitrogen at the surface of the metal is decreased, while the concentration of nitrogen at the molten Ga−substrate interface is increased, which allows for liquid-phase epitaxy of GaN.

show abstract

Synergistic interactions of H2 and N2 with molten gallium in the presence of plasma

Cited by 12 publications

References 32 publications

Enhancement of the Yield of Ammonia by Hydrogen‐Sink Effect during Plasma Catalysis

Enhancement of the Yield of Ammonia by Hydrogen‐Sink Effect during Plasma Catalysis

Review of low-temperature plasma nitrogen fixation technology

Liquid Phase Epitaxy of Gallium Nitride

Contact Info

Product

Resources

About