Comparative X-ray Photoelectron Spectroscopic Study on the Desulfurization of Thiophene by Raney Nickel and Rapidly Quenched Skeletal Nickel

Abstract

The desulfurization of thiophene on Raney Ni and rapidly quenched skeletal Ni (RQ Ni) has been studied in ultrahigh vacuum (UHV) by X-ray photoelectron spectroscopy (XPS). The Raney Ni or RQ Ni can be approximated as a hydrogen-preadsorbed polycrystalline Ni-alumina composite. It is found that thiophene molecularly adsorbs on Raney Ni or RQ Ni at 103 K. At 173 K, thiophene on alumina is desorbed, while thiophene in direct contact with the metallic Ni in Raney Ni undergoes C-S bond scission, leading to carbonaceous species most probably in the metallocycle-like configuration and atomic sulfur. On RQ Ni, the temperature for thiophene dissociation is about 100 K higher than that on Raney Ni. The lower reactivity of RQ Ni toward thiophene is tentatively attributed to lattice expansion of Ni crystallites in RQ Ni due to rapid quenching. The existence of alumina and hydrogen may block the further cracking of the metallocycle-like species on Raney Ni and RQ Ni at higher temperatures, which has been the dominant reaction pathway on Ni single crystals. By 473 K, the C 1s peak has disappeared, leaving nickel sulfide on the surface.

Surface functionalization of electro-deposited nickel

“…21,26,27 Another point to consider is that atomic S in the form of NiS exhibits a BE range from 161.0 to 162.2 eV overlapping in some extent the BE range expected for thiolates. 26,28 On the basis of our data we can not therefore discard the presence of some amount of S in a mixed S/octanethiol monolayer which could explain the enhanced HER reaction observed in our samples. A mixed S/methanethiol monolayer has been previously predicted on palladium by Carro et al 29 (Using DFT calculations they found that the type of monolayer varied depending on the experimental factors and that a mixed layer of S and methanethiol was possible.…”

One-step synthesis of Ni3S2 nanoparticles wrapped with in situ generated nitrogen-self-doped graphene sheets with highly improved electrochemical properties in Li-ion batteries

“…2d), the peaks at 164 eV and 162.4 eV can be indexed to atomic S and S2p 3/2 sulfur in Ni 3 S 2 , respectively. 4,37 The SEM micrographs (Fig. 3a-c) show that the Ni 3 S 2 @N-G composite possesses an assembled layer structure consisting of transparent N-graphene sheets and Ni 3 S 2 particles.…”

Amorphous Ni Alloy Hydrogenation Catalyst and Magnetically Stabilized Bed Reaction Technology

“…The SRNA-1 and SRNA-2 catalysts can meet the requirements for hydrogenating a variety of unsaturated functional groups. The SRNA-3 catalyst with a lower atomic coordination number is prepared after increasing the rotational speed of the copper cooling roller to enhance the cooling effect and is used in the adsorption/desulfurization process [7,8]. Since the magnetic property of the SRNA series catalysts must be further enhanced to cope with the needs of magnetic separation technique and magnetically stabilized bed, the highly magnetically susceptible SRNA-4 catalyst is prepared by introducing iron into the catalyst composition [9].…”