Synergistic Coupling of a Molybdenum Carbide Nanosphere with Pt Nanoparticles for Enhanced Ammonia Electro-Oxidation Activity in Alkaline Media

Bayati, Maryam; Liu, Xiaoteng; Abellán, Patricia; Pocock, Dan; Dixon, Michael L.; Scott, Keith

doi:10.1021/acsaem.9b01979

Cited by 17 publications

(7 citation statements)

References 66 publications

(138 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recently, electrocatalytic oxidation of ammonia (AEO) has attracted much attention of researchers and scientists because, as a hydrogen-rich carrier, it possesses 70% higher volumetric hydrogen content than pure liquid hydrogen [5,6]. Theoretical and experimental investigations reveal that hydrogen generation via ammonia electro-oxidation (AEO) is a cost-effective approach compared to water electrolysis because it requires much lower oxidation potential (0.06 V) than water (−1.23 V), as described in Equations (1-3) [7,8]. Theoretical ammonia electrolysis consumes energy of about~1.55 Wh•g −1 H 2 at standard conditions, which is 95% less than water electrolysis [9].…”

Section: Introductionmentioning

confidence: 99%

“…To commercialize this direct ammonia fuel cell (DAFC) technology, an efficient, stable, and economical electrocatalyst is required. Thus far, expensive noble metal-based (Pt, Ru, Ir, Rh, Pd) alloys are considered as the best performing AEO catalysts [5][6][7][8]15,16]. Sluggish reaction kinetics of AEO, high cost and low resistance to poisoning by reaction intermediates of these catalysts hinder this technology in commercialization.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Electro-Oxidation of Ammonia over Copper Oxide Impregnated γ-Al2O3 Nanocatalysts

et al. 2021

View full text Add to dashboard Cite

Ammonia electro-oxidation (AEO) is a zero carbon-emitting sustainable means for the generation of hydrogen fuel, but its commercialization is deterred due to sluggish reaction kinetics and the poisoning of expensive metal electrocatalysts. With this perspective, CuO impregnated γ-Al2O3 (CuO/γ-Al2O3) hybrid materials were synthesized as effective and affordable electrocatalysts and investigated for AEO in alkaline media. Structural investigations were performed via different characterization techniques, i.e., X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electrochemical impedance spectroscopy (EIS). The morphology of γ-Al2O3 support as interconnected porous structures rendered the CuO/γ-Al2O3 nanocatalysts with robust activity. The additional CuO impregnation resulted in the enhanced electrochemical active surface area (ECSAs) and diffusion coefficient and spiked the electrocatalytic performance for NH3 electrolysis. Owing to good values of diffusion coefficient for AEO, low bandgap, and availability of ample ECSA at higher CuO to γ-Al2O3 ratio, these proposed electrocatalysts were proved to be effective in AEO. Due to good reproducibility, electrochemical stability, and higher activity for ammonia electro-oxidation, CuO/γ-Al2O3 nanomaterials are proposed as efficient promoters, electrode materials, or catalysts in ammonia electrocatalysis.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Electro-Oxidation of Ammonia over Copper Oxide Impregnated γ-Al2O3 Nanocatalysts

et al. 2021

View full text Add to dashboard Cite

show abstract

“…13 During the survey scan of Mo-ECs (MoN, Mo 2 C, and MoS 2 ) nanomaterials, MoO x phases (MoO 2 and MoO 3 ) were also detected, which suggests that Mo species were either oxidized during the synthesis process or absorbed or contaminated by atmospheric oxygen [32,50,56,95,96]. Bayati et al [97] suggested that various oxidation states, such as Mo 2+ , Mo 3+ , Mo 5+ , and Mo 6+ as in a single Mo, can be linked to the presence of carbide, nitride, and oxide species, respectively [97,98]. A positive shift of 0.2 eV compared to the Pt 4f 7/2 of pure Pt can be attributed to an induced positive charge on the dis-…”

Section: X-ray Photoelectron Spectroscopymentioning

confidence: 98%

Molybdenum–Based Electrocatalysts for Direct Alcohol Fuel Cells: A Critical Review

Yogesh,

Yeetsorn,

Wanchan

et al. 2024

J. Electrochem. Sci. Technol

View full text Add to dashboard Cite

Direct alcohol fuel cells (DAFCs) have gained much attention as promising energy conversion devices due to their ability to utilize alcohol as a fuel source. In this regard, Molybdenum-based electrocatalysts (Mo-ECs) have emerged as a substitution for expensive Pt and Ru–based co-catalyst electrode materials in DAFCs, owing to their unique electrochemical properties useful for alcohol oxidation. The catalytic activity of Mo-ECs displays an increase in alcohol oxidation current density by several folds to 1000–2000 mA mgPt−1, compared to commercial Pt and PtRu catalysts of 10–100 mA mgPt−1. In addition, the methanol oxidation peak and onset potential have been significantly reduced by 100–200 mV and 0.5–0.6 V, respectively. The performance of Mo-ECs in both acidic and alkaline media has shown the potential to significantly reduce the Pt loading. This review aims to provide a comprehensive overview of the bifunctional mechanism involved in the oxidation of alcohols and factors affecting the electrocatalytic oxidation of alcohol, such as synthesis method, structural properties, and catalytic support materials. Furthermore, the challenges and prospects of Mo-ECs for DAFCs anode materials are discussed. This in-depth review serves as valuable insight toward enhancing the performance and efficiency of DAFC by employing Mo-ECs.

show abstract

“…In response to restraining the activity loss of nickel‐based catalysts, the contribution of metal compounds (e.g., MO x , [ 65 ] M(OH) x , [ 90 ] MC x [ 91 ] ) to their doping modification was also studied. Huang et al reported a nanostructured catalyst of Cu 2 O wire‐in‐Ni(OH) 2 plate passivated by a thin CuO surface, which can stably electrolyze alkaline ammonia solution into hydrogen and nitrogen at a high current density of 80 mA cm −2 ( Figure a,f).…”

Section: Electrocatalysts For the Aormentioning

confidence: 99%

Green Chemistry: Advanced Electrocatalysts and System Design for Ammonia Oxidation

et al. 2023

View full text Add to dashboard Cite

Fossil fuels, including coal, petroleum, and natural gas, are still the main sources of energy supply in the world at present. [1,2] Their nonrenewable nature, however, determines that the total amount of these fossil fuels is limited, thus leading to the potential energy crisis. [3,4] This issue has given a strong impetus to the development of green, safe, and renewable energy supplies, such as wind, solar, and tide energy. [5][6][7][8] Although these novel energy sources are generally sustainable, their direct utilization is extremely difficult. For example, these green energy types, especially solar energy, commonly suffer high fluctuation, thus leading to the misalignment of electricity generation of these energies with the actual demand. [9] Therefore, it is very important to explore and exploit the optimal secondary energy carriers. Among the secondary energy carriers, hydrogen is one of the most economical and eco-friendly carriers due to its zero-carbon emission, abundance, high energy density (120 MJ kg À1 ), etc. [10][11][12] Due to the potential safety hazards in the storage and transportation of hydrogen gas, nevertheless, its practical utilization has great limitations. [13,14] To address these issues, it has been suggested to use methane or ammonia gas as the hydrogen carriers. [15][16][17][18] Methane has a wide range of resources and mature industrial processing technologies. Thermal catalytic decomposition of methane and steam reforming is the most mature technology of hydrogen generation in the industry currently. [19,20] However, the transportation and storage of methane remain problematic owing to its physical characteristics, which are similar to those of hydrogen. As a cost-effective hydrogen carrier, ammonia can turn into a liquid state at room temperature under moderate pressure (%8 bar), much milder than that hydrogen gas (690 bar and 15 °C). [10,21,22] Besides, the utilization of ammonia does not associate with greenhouse gas emissions. Moreover, the energy density of liquid ammonia (11.5 MJ kg À1 ) is also higher than that of liquid hydrogen (8.5 MJ kg À1 ). Moreover, the presence of ammonia can be easily detected even at a very low concentration of 1 ppm, allowing ammonia leaks to be assessed and dealt with in a timely manner. In addition, unlike hydrogen, ammonia is widely used and vastly produced (global production is 176 million tons a year) around the world in the pharmaceutical, fertilizer, and chemical industries. Consequently, the well-established and mature ammonia production-related infrastructure makes ammonia a viable energy source. [23][24][25][26] To utilize ammonia for energy applications, electrochemical ammonia oxidation reaction (AOR) is essential, either for hydrogen production via ammonia splitting or electricity generation via direct ammonia fuel cells (DAFCs), which are highly commercially promising. During operation, DAFCs just produce water and nitrogen gas. [22,[27][28][29] In addition, ammonia fuel cells are also theoretically superior to their hydrogen-based c...

show abstract

Synergistic Coupling of a Molybdenum Carbide Nanosphere with Pt Nanoparticles for Enhanced Ammonia Electro-Oxidation Activity in Alkaline Media

Cited by 17 publications

References 66 publications

Electro-Oxidation of Ammonia over Copper Oxide Impregnated γ-Al2O3 Nanocatalysts

Electro-Oxidation of Ammonia over Copper Oxide Impregnated γ-Al2O3 Nanocatalysts

Molybdenum–Based Electrocatalysts for Direct Alcohol Fuel Cells: A Critical Review

Green Chemistry: Advanced Electrocatalysts and System Design for Ammonia Oxidation

Contact Info

Product

Resources

About