Growth mechanism of graphite-carbon encapsulated nickel catalysts and curvature effect of carbon layer on the performance of catalytic hydrogenation

He, Wei; Yu, Jiaxin; Zhang, Xiyuan; Zhou, Yongbo; Yao, YongYue; Ma, Chaojie; Yin, Chunyu; Yan, Wei; Liu, Yi; Lu, Chunshan; Li, Xiaonian

doi:10.1016/j.apcatb.2023.122738

Cited by 16 publications

(7 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The largest weight-loss interval, about 30%, occurred at 310–650 °C, which was due to the collapse and decomposition of the OCP structure, leading to the appearance of CO 2 , CO, and EtOH signals in the MS curves in the corresponding temperature interval . In addition, the signals of water appearing in the high-temperature phase shown in the MS spectrum, as well as that of the reducing gases CO and C 2 H 4 , suggested that the exothermic peak accompanying the second and third weight-loss intervals might be associated with redox reactions occurring throughout the pyrolysis procedure . As the temperature continued to rise, the weight loss of the sample stabilized, with a total weight loss of approximately 50%.…”

Section: Resultsmentioning

confidence: 99%

“…The apparent activation energy ( E a ) of the catalyst Fe@C-2 in the hydrogenation of p -CNB was determined by kinetic experiments at the temperature range of 313.15–403.15 K . By linear fitting the data of ln c p ‑CNB and ln r , a straight line could be obtained, and its slope represented the reaction order in the hydrogenation of p -CNB.…”

Section: Resultsmentioning

confidence: 99%

“…44 In addition, the signals of water appearing in the high-temperature phase shown in the MS spectrum, as well as that of the reducing gases CO and C 2 H 4 , suggested that the exothermic peak accompanying the second and third weightloss intervals might be associated with redox reactions occurring throughout the pyrolysis procedure. 45 As the temperature continued to rise, the weight loss of the sample stabilized, with a total weight loss of approximately 50%. Therefore, 700 °C was determined as the pyrolysis temperature based on the TGA results.…”

Section: Synthesis and Characterizations Of Fe@c-2mentioning

confidence: 98%

“…The D 4 band, generally appearing at about 1200 cm −1 , was only found in very poorly organized materials such as coal coke and soot. 45,54,55 The intensity ratio of the D 1 peak to the G peak in the Raman spectrum held significant meaning and had been proven to correlate well with the extent of the structure defects in carbon-based materials like graphite and graphene. 56 As the amount of ammonia added increased, the intensity ratio of D 1 peak and G peak of the catalyst material changed, which was 1.18, 0.83, 0.93, and 1.24, respectively, with an overall trend of decreasing and then increasing.…”

Section: Regulation Of Catalyst Structurementioning

confidence: 99%

“…After 10 cycles, the catalyst still exhibited catalytic activity, the conversion remained stable (about 75%), the selectivity to p-CAN remained high (exceeding 99%), and there was no significant change in the catalyst composition (Figure S5). The apparent activation energy (E a ) of the catalyst Fe@C-2 in the hydrogenation of p-CNB was determined by kinetic experiments at the temperature range of 313.15−403.15 K. 45 By linear fitting the data of ln c p-CNB and ln r, a straight line could be obtained, and its slope represented the reaction order in the hydrogenation of p-CNB. As shown in Figure 5c, the selective hydrogenation of p-CNB with Fe@C-2 as a catalyst was a zero-order reaction.…”

Section: Regulation Of Catalyst Structurementioning

confidence: 99%

See 4 more Smart Citations

Iron-Based Catalysts with Oxygen Vacancies Obtained by Facile Pyrolysis for Selective Hydrogenation of Nitrobenzene

Yu,

Zhang,

Jiang

et al. 2024

ACS Appl. Mater. Interfaces

Self Cite

View full text Add to dashboard Cite

The development of preparation strategies for iron-based catalysts with prominent catalytic activity, stability, and cost effectiveness is greatly significant for the field of catalytic hydrogenation but still remains challenging. Herein, a method for the preparation of iron-based catalysts by the simple pyrolysis of organometallic coordination polymers is described. The catalyst Fe@C-2 with sufficient oxygen vacancies obtained in specific coordination environment exhibited superior nitro hydrogenation performance, acid resistance, and reaction stability. Through solvent effect experiments, toxicity experiments, TPSR, and DFT calculations, it was determined that the superior activity of the catalyst was derived from the contribution of sufficient oxygen vacancies to hydrogen activation and the good adsorption ability of FeO on substrate molecules.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Synthesis and Characterizations Of Fe@c-2mentioning

confidence: 98%

Section: Regulation Of Catalyst Structurementioning

confidence: 99%

Section: Regulation Of Catalyst Structurementioning

confidence: 99%

See 3 more Smart Citations

Iron-Based Catalysts with Oxygen Vacancies Obtained by Facile Pyrolysis for Selective Hydrogenation of Nitrobenzene

Yu,

Zhang,

Jiang

et al. 2024

ACS Appl. Mater. Interfaces

Self Cite

View full text Add to dashboard Cite

show abstract

Unveiling the Synergistic Role of Frustrated Lewis Pairs in Carbon‐Encapsulated Ni/NiO_x Photothermal Cocatalyst for Enhanced Photocatalytic Hydrogen Production

Yang,

Huang,

et al. 2024

Advanced Materials

View full text Add to dashboard Cite

The development of high‐density and closely spaced frustrated Lewis pairs (FLPs) is crucial for enhancing catalyst activity and accelerating reaction rates. However, constructing efficient FLPs by breaking classical Lewis bonds poses a significant challenge. Here, we have made a pivotal discovery regarding the Jahn‐Teller effect during the formation of grain boundaries in carbon‐encapsulated Ni/NiOx (Ni/NiOx@C). This effect facilitates the formation of high‐density O (VO) and Ni (VNi) vacancy sites with different charge polarities, specifically FLP‐VO‐C basic sites and FLP‐VNi‐C acidic sites. The synergistic interaction between FLP‐VO‐C and FLP‐VNi‐C sites not only reduces energy barriers for water adsorption and splitting, but also induces a strong photothermal effect. This mutually reinforcing effect contributes to the exceptional performance of Ni/NiOx@C as a cocatalyst in photothermal‐assisted photocatalytic hydrogen production. Notably, the Ni/NiOx@C/g‐C3N4 (NOCC) composite photocatalyst exhibits remarkable hydrogen production activity with a rate of 10.7 mmol•g−1•h−1, surpassing that of the Pt cocatalyst by 1.76 times. Moreover, the NOCC achieves an impressive apparent quantum yield of 40.78% at a wavelength of 380 nm. This work paves the way for designing novel defect‐state multiphase cocatalysts with high‐density and adjacent FLP sites, which hold promise for enhancing various catalytic reactions.This article is protected by copyright. All rights reserved

show abstract

Inducing One‐Step Dehydrogenation of Magnesium Borohydride via Confinement in Robust Dodecahedral Nitrogen‐Doped Porous Carbon Scaffold

Jia,

Han,

Wang

et al. 2024

Advanced Materials

View full text Add to dashboard Cite

A dodecahedral activated N‐doped porous carbon scaffold is synthesized and used for the nanoconfinement of Mg(BH4)2. The optimized mesoporous scaffold possesses an accumulated pore width of 2.65 nm, high specific surface area (3955.9 m2 g−1), and large pore volume (2.15 cm3 g−1), providing ample space for the confinement of Mg(BH4)2 particles and numerous surface active sites for interactions with the same. The confined Mg(BH4)2 system features a dehydrogenation onset temperature of 81.5 °C, an extremely high capacity of 10.2 wt% H2, and an almost single‐step dehydrogenation profile. Moreover, the system exhibits superior capacity retention of 82.7% after 20 cycles at a moderate temperature of 250 °C. Precise activation control enables a transformation from microporous carbon materials to mesoporous ones, and hence the efficient nanoconfinement of Mg(BH4)2 and realization of one‐step dehydrogenation. The evolution of borohydride intermediates is systematically revealed throughout the cycling process. Density functional theory calculations demonstrate defective N heteroatoms within the scaffold are vital in reducing the strength of B─H bonds, and the N‐doped carbon can facilitate decomposition of the irreversible MgB12H12 intermediate. This study opens up new avenues for designing robust carbon scaffolds doped with heteroatoms and analyzing intermediate evolution in nanoconfined Mg‐based borohydride systems.

show abstract

Growth mechanism of graphite-carbon encapsulated nickel catalysts and curvature effect of carbon layer on the performance of catalytic hydrogenation

Cited by 16 publications

References 63 publications

Iron-Based Catalysts with Oxygen Vacancies Obtained by Facile Pyrolysis for Selective Hydrogenation of Nitrobenzene

Iron-Based Catalysts with Oxygen Vacancies Obtained by Facile Pyrolysis for Selective Hydrogenation of Nitrobenzene

Unveiling the Synergistic Role of Frustrated Lewis Pairs in Carbon‐Encapsulated Ni/NiO_x Photothermal Cocatalyst for Enhanced Photocatalytic Hydrogen Production

Inducing One‐Step Dehydrogenation of Magnesium Borohydride via Confinement in Robust Dodecahedral Nitrogen‐Doped Porous Carbon Scaffold

Contact Info

Product

Resources

About

Growth mechanism of graphite-carbon encapsulated nickel catalysts and curvature effect of carbon layer on the performance of catalytic hydrogenation

Cited by 16 publications

References 63 publications

Iron-Based Catalysts with Oxygen Vacancies Obtained by Facile Pyrolysis for Selective Hydrogenation of Nitrobenzene

Iron-Based Catalysts with Oxygen Vacancies Obtained by Facile Pyrolysis for Selective Hydrogenation of Nitrobenzene

Unveiling the Synergistic Role of Frustrated Lewis Pairs in Carbon‐Encapsulated Ni/NiOx Photothermal Cocatalyst for Enhanced Photocatalytic Hydrogen Production

Inducing One‐Step Dehydrogenation of Magnesium Borohydride via Confinement in Robust Dodecahedral Nitrogen‐Doped Porous Carbon Scaffold

Contact Info

Product

Resources

About

Unveiling the Synergistic Role of Frustrated Lewis Pairs in Carbon‐Encapsulated Ni/NiO_x Photothermal Cocatalyst for Enhanced Photocatalytic Hydrogen Production