• 文献标题:   Engineering hydrogenation active sites on graphene oxide and N-doped graphene by plasma treatment
  • 文献类型:   Article
  • 作  者:   MAGUREANU M, MANDACHE NB, RIZESCU C, BUCUR C, COJOCARU B, MAN IC, PRIMO A, PARVULESCU VI, GARCIA H
  • 作者关键词:   graphene oxide as catalyst, ndoped graphene as catalyst, hydrogen plasma activation of graphene, 1octene hydroisomerization, alphamethylstyrene hydrogenation
  • 出版物名称:   APPLIED CATALYSIS BENVIRONMENTAL
  • ISSN:   0926-3373 EI 1873-3883
  • 通讯作者地址:  
  • 被引频次:   7
  • DOI:   10.1016/j.apcatb.2021.119962 EA FEB 2021
  • 出版年:   2021

▎ 摘  要

Graphene oxide (GO) and N-doped graphene [(N)G] graphenes were submitted to H-2 glow discharge under different discharge regimes, in both the negative glow and positive column plasma regions. The resulted catalysts were fully characterized using several techniques such as Raman, DRIFT and XPS spectroscopy, powder X-ray diffraction, H-2 pulse chemisorption and H-2-, CO2- and NH3-TPD experiments. Density functional theory calculations were performed taking a slab model of graphene sheet with an optimized C-C bond length (1.426 angstrom) and a 16 angstrom vacuum layer between sheets. An overview of these characterizations showed that the O/C atomic ratio of GO is influenced by the plasma regime, indicating the occurrence of O removal, as also predicted by DFT calculations. In the case of (N)G, the plasma treatment also removes pyridinic N with an increase of the C/N ratio. The efficiency of the plasma modification has been checked through catalytic tests in hydroisomerization of 1-octene and hydrogenation of alpha-methyl-styrene. Contrarily to classical thermal activation requiring high temperatures, the generation of the defects by treating with plasma occurs at voltages in the range of 2 5 kV. In consequence, the hydrogenation and isomerization of alkenes resulted with high yields and good selectivities. Graphene prepared from sodium alginate from brown algae was considered as reference in these investigations.