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Title: Reactive Intermediates or Inert Graphene? Temperature- and Pressure-Determined Evolution of Carbon in the CH 4–Ni(111) System

Abstract

Atomic-level identification of carbon intermediates under reaction conditions is essential for carbon-related heterogeneous catalysis. Using the in operando technique of near-ambient-pressure X-ray photoelectron spectroscopy, we have identified in this paper various carbon intermediates during the thermal decomposition of CH 4 on Ni(111), including *CH, *C 1/Ni 3C, *C n (n ≥ 2), and clock-reconstructed Ni 2C at different temperature regions (300–900 K). These “reactive” carbon precursors can either react with probing molecules such as O 2 at room temperature or be etched away by CH 4. They can also develop into graphene flakes under controlled conditions: a temperature between 800 and 900 K and a suitable CH 4 pressure (10 –3–10 –1 mbar, depending on temperature). The growth rate of graphene is significantly restrained at higher CH 4 pressures, due to the accelerated etching of its carbon precursors. The identification of in operando carbon intermediates and the control of their evolution have great potential in designing heterogeneous catalysts for the direct conversion of methane. Finally, the observed carbon aggregation/etching equilibrium reveals an underlying mechanism in coking prevention and in the fabrication of large-area single-crystal graphene, where the suppression of seeding density and etching up of small grains are required.

Authors:
ORCiD logo [1]; ORCiD logo [2];  [3];  [3];  [3];  [1]
  1. National Univ. of Singapore (Suzhou) Research Inst., Suzhou (China); National Univ. of Singapore (Singapore)
  2. Brookhaven National Lab. (BNL), Upton, NY (United States)
  3. National Univ. of Singapore (Singapore)
Publication Date:
Research Org.:
National Univ. of Singapore (Singapore); National Univ. of Singapore (Suzhou) Research Inst., Suzhou (China); Brookhaven National Lab. (BNL), Upton, NY (United States)
Sponsoring Org.:
USDOE; National Natural Science Foundation of China (NNSFC)
OSTI Identifier:
1407473
Report Number(s):
BNL-114500-2017-JA
Journal ID: ISSN 2155-5435; R&D Project: 16068; KC0403020
Grant/Contract Number:
SC0012704; 91645102
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
ACS Catalysis
Additional Journal Information:
Journal Volume: 7; Journal Issue: 9; Journal ID: ISSN 2155-5435
Publisher:
American Chemical Society (ACS)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; carbon; catalyst; graphene; intermediate; methane; NAP-XPS; nickel

Citation Formats

Yuan, Kaidi, Zhong, Jian-Qiang, Sun, Shuo, Ren, Yinjuan, Zhang, Jia Lin, and Chen, Wei. Reactive Intermediates or Inert Graphene? Temperature- and Pressure-Determined Evolution of Carbon in the CH4–Ni(111) System. United States: N. p., 2017. Web. doi:10.1021/acscatal.7b01880.
Yuan, Kaidi, Zhong, Jian-Qiang, Sun, Shuo, Ren, Yinjuan, Zhang, Jia Lin, & Chen, Wei. Reactive Intermediates or Inert Graphene? Temperature- and Pressure-Determined Evolution of Carbon in the CH4–Ni(111) System. United States. doi:10.1021/acscatal.7b01880.
Yuan, Kaidi, Zhong, Jian-Qiang, Sun, Shuo, Ren, Yinjuan, Zhang, Jia Lin, and Chen, Wei. 2017. "Reactive Intermediates or Inert Graphene? Temperature- and Pressure-Determined Evolution of Carbon in the CH4–Ni(111) System". United States. doi:10.1021/acscatal.7b01880.
@article{osti_1407473,
title = {Reactive Intermediates or Inert Graphene? Temperature- and Pressure-Determined Evolution of Carbon in the CH4–Ni(111) System},
author = {Yuan, Kaidi and Zhong, Jian-Qiang and Sun, Shuo and Ren, Yinjuan and Zhang, Jia Lin and Chen, Wei},
abstractNote = {Atomic-level identification of carbon intermediates under reaction conditions is essential for carbon-related heterogeneous catalysis. Using the in operando technique of near-ambient-pressure X-ray photoelectron spectroscopy, we have identified in this paper various carbon intermediates during the thermal decomposition of CH4 on Ni(111), including *CH, *C1/Ni3C, *Cn (n ≥ 2), and clock-reconstructed Ni2C at different temperature regions (300–900 K). These “reactive” carbon precursors can either react with probing molecules such as O2 at room temperature or be etched away by CH4. They can also develop into graphene flakes under controlled conditions: a temperature between 800 and 900 K and a suitable CH4 pressure (10–3–10–1 mbar, depending on temperature). The growth rate of graphene is significantly restrained at higher CH4 pressures, due to the accelerated etching of its carbon precursors. The identification of in operando carbon intermediates and the control of their evolution have great potential in designing heterogeneous catalysts for the direct conversion of methane. Finally, the observed carbon aggregation/etching equilibrium reveals an underlying mechanism in coking prevention and in the fabrication of large-area single-crystal graphene, where the suppression of seeding density and etching up of small grains are required.},
doi = {10.1021/acscatal.7b01880},
journal = {ACS Catalysis},
number = 9,
volume = 7,
place = {United States},
year = 2017,
month = 8
}

Journal Article:
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