Raman Spectra of Synthetic ‘Braggite’, (Pd,Pt,Ni)S

Abstract

Raman spectra of synthetic 'braggite' ((Pd,Pt,Ni)S) vary systematically with changes in Pt/Pd ratios, but this change is less pronounced than in 'cooperite' ((Pt,Pd,Ni)S). Compared to 'vysotskite' (ideally PdS), the incorporation of Pt leads to broadening of bands but the spectra of 'vysotskite' and 'braggite' are similar, and spectra of 'cooperite' and the 'braggite/vysotskite' solid-solution series are sufficiently different to facilitate distinction of these platinum group minerals by Raman spectroscopy.KEYWORD$" Raman spectroscopy, braggite, mineral chemistry, platinum group minerals.

Surface-State Assisted Carrier Recombination and Optical Nonlinearities in Bulk to 2D Nonlayered PtS

“…In addition to this, a distinct shoulder on the low wavenumber side was observed (see Figure S4 for detail). This shoulder probably results from the degenerate E g mode at ∼326 cm –1 , which is in good agreement with the results obtained for natural cooperite mineral by Merkle and Pikl et al . , However, we did not observe any distinct second-order Raman peak at 347 and 365 cm –1 , as reported by Mernagh et al . A slight shift of Raman peaks among PtS films with different thicknesses might be ascribed to the degenerate E g mode and low signal-to-noise ratio for thinner sample during the measurements, which negatively affects the determination of B 1g and E g modes (Table S2).…”

Tuning and Locking the Localized Surface Plasmon Resonances of CuS (Covellite) Nanocrystals by an Amorphous CuPdxS Shell

“…40 If these samples were annealed at 100 °C under a N 2 atmosphere for 1 h, their Raman spectra evidenced new peaks at 323, 346, and 386 cm −1 (Figure S4d−f), which are due to Pd−S vibrational modes. 45,46 Progressive breaking of the S−S bonds of the initial covellite lattice was also proven by high-resolution XPS analysis (Figure 1f and Figure S5). The evolution of characteristic peaks observed in the S 2p region, which permits the discrimination between sulfides and disulfides (S−S covalent bonds), indeed, confirmed the gradual fading of the S−S signal as the shell grew progressively thicker.…”

“… 40 If these samples were annealed at 100 °C under a N 2 atmosphere for 1 h, their Raman spectra evidenced new peaks at 323, 346, and 386 cm –1 ( Figure S4d–f ), which are due to Pd–S vibrational modes. 45 , 46 …”

Strategy for Fabricating Wafer-Scale Platinum Disulfide

“…Figure S3 shows the Raman spectra of the same PtS sample before and after multi-interchangeable conversions. Before conversion, only a relatively weak peak around 330 cm –1 is observed from the Raman spectrum . After conversion, three strong peaks around 302, 331, and 343 cm –1 show up, indicating that the PtS has been converted into PtS 2 .…”

“…Liquid exfoliation provides a huge yield but lacks intrinsic quality and homogeneity . Direct sulfurizing/selenizing of transition-metal thin films can produce transition-metal dichalcogenide (TMD) thin films with high throughput and quality, making it compatible with conventional planar technologies. ,− Compared with the conventional CVD process, this thermally assisted conversion method shows better controllability and reproducibility. − However, sulfurization of Pt can result in both PtS and PtS 2 phases, and the tetragonal PtS with its three-dimensional (3D) crystal structure is more stable than its hexagonal 2D counterpart, PtS 2 . Here, we for the first time synthesized thin-film PtS 2 through sulfurization of Pt in a scalable and controllable manner.…”