Probing the structure and functionalized surface of colloidal AuSe

• Published in: Materials science & engineering. B, Solid-state materials for advanced technology Solid-state materials for advanced technology, 2021-01, Vol.263, p.114878, Article 114878
• Main Authors: Machogo, Lerato F.E., Sithole, Rudo K., Phao, Neo, Kolokoto, Tshwarela, Gqoba, Siziwe S., Mlambo, Mbuso, Moloto, Makwena J., Shumbula, Poslet M., Mdluli, Phumlane S., Moloto, Nosipho
• Format: Article
• Language: English
• Subjects: Capping; Capping agents; Gold selenide; Layered materials; Ligands; Nanorods; Oleic acid; Raman spectra; Raman spectroscopy; XPS
• ISSN: 0921-5107; 1873-4944
• DOI: 10.1016/j.mseb.2020.114878

•Novel colloidal synthesis of a less explored 2D material, AuSe nanobelts.•Corroborating the mixed oxidation of AuSe previously observed in the X-ray crystal structure by Raman spectroscopy and XPS.•Determining the effect of the capping agent on the properties of AuSe. We report on the synthesis of the less explored AuSe and investigate the influence capping agents; oleylamine (OLA), 1-dodecanethiol (IDDT), and oleic acid (OA) have on its structure and surface. TEM showed long belt-like structures for both OLA and OA-capped materials and nanorods for 1DDT-AuSe. XRD diffractograms and Raman spectra showed the presence of both α- and β-AuSe polymorphs, with the dominance of the α-phase in all three materials. The methylene stretching frequencies in the FTIR spectra confirmed capping by the organic ligands. High-resolution XPS spectra of the Au4f core level showed evidence of the Au + ions. The high total peak area percentage of the Au + ions in OLA-AuSe (90%), 1DDT (23%), and OA (21%) suggests that OLA is the best capping ligand. DFT calculations on the adsorption of the ligands on AuSe showed weak interaction on (001) plane suggesting anisotropic growth along this plane and preference for the α-phase.