Selective Growth of Metal Sulfide, Metal, and Metal-Alloy on 2D CdS Nanoplates

Abstract

Two-dimensional CdS-based hybrid nanostructures are intriguing materials with an application prospect in different fields such as sensing (i. e., photoresistors) and solar energy harvesting (photocatalysis, photovoltaics, and so forth). We report herein a colloidal synthetic path for interfacing metal and semiconductor with 2D CdS nanoplates. Selective growth of Au, Pt, and a PtNi alloy as well as Cu 2−x S semiconductor is achieved on CdS nanoplates using controlled reduction of metallic precursors and thermal decomposition of a metal-sulfide single-source precursor using standard organic-phase colloidal chemistry.

Rich Landscape of Colloidal Semiconductor–Metal Hybrid Nanostructures: Synthesis, Synergetic Characteristics, and Emerging Applications

“…60 Additionally, aqueous condensation of Pd II onto CdS NRs was reported by Shemesh et al 50 As Au growth was utilized on 2D nanosystems, implementation of the described oleylamineassisted synthetic route was also conducted on NPLs. Typically, Pt or Pd metal domains were deposited on the edges of homogeneous or heterostructure semiconductor NPLs resulting in CdSe−Pt, 41 CdSe−Pd, 41 CdS−Pt, 37,61 irradiation of the semiconductor, the absorbed photon generates the formation of an excited charge carrier within the semiconductor, namely, an electron−hole pair. These charge carriers, typically electrons, may accumulate at the defect site or preexisting metal domains through a suitable relaxation route.…”

“…More recently, with the synthetic development of 2D nanoplatelet-like semiconductor structures (NPLs), their semiconductor–metal hybrid forms were generated also. This includes CdS–Au, , CdSe–Au, − and CdSe/CdS–Au. , Various HNPs with different morphologies and material compositions which were synthesized via this approach are shown in Figure .…”

“…Additionally, aqueous condensation of Pd II onto CdS NRs was reported by Shemesh et al As Au growth was utilized on 2D nanosystems, implementation of the described oleylamine-assisted synthetic route was also conducted on NPLs. Typically, Pt or Pd metal domains were deposited on the edges of homogeneous or heterostructure semiconductor NPLs resulting in CdSe–Pt, CdSe–Pd, CdS–Pt, , and CdSe/CdS–Pt (Figure ). Recently, a modified reducing procedure for Au deposition on nanoplatelets was presented by Mews et al where CuS–Au hybrid NPLs were obtained in the presence of oxalic acid and oleylamine …”

Metal/semiconductor interfaces in nanoscale objects: synthesis, emerging properties and applications of hybrid nanostructures

“…79 The CO served a dual role-it reduced the Pt(acac) 2 on the pre-formed Pt-tip and also dictated the nal {100} faceted tip morphology. Some examples of different adaptations of the abovementioned selective deposition methods of gold and platinum resulted in CdSe pyramids/Au, 80 PbS QDs/Au, 81 PbSe QDs/ multiple-domain(s) and sizes of Au, 82 PbTe nanocubes/Au, 83 Ag 2 Se/Au and Ag 3 AuSe 2 /Au, 84 Cu 2 ZnSnS 4 (CZTS, a Cd-free SC with E g $ 1.5 eV) cubes/Au and /Pt, 85 NRs/Au, 86 core@shell or heterodimers with Pt, Pd and Au, 87 QDs/AuAg, 88 CuInS 2 /Pt, 89 CdSe@CdS NR/Pt, 90 CdSe@CdS NR/Co, 57 CdSe@CdS NR/Ni, 91 Bi 2 S 3 /Au nano-dumbbells, 92 anisotropic quasi-2D CdSe nanosheets or nanoplatelets (NPLs) 70,[93][94][95][96] and related 2D cadmium chalcogenides (e.g., CdS 96,97 and CdSe-CdS core-crown NPLs 94,95 ) with metals such as /Au, 70,[93][94][95]97 /Pt, [93][94][95][96][97] /Pd, 93 metal alloys such as Pt-Au 95 and Ni-Pt, 97 as well as selective deposition of distinguishable Pt and Au domains. 95 The mentioned variations include changes to the shape, size, morphology and material of the starting SC, as well as expansion of the deposited metals and alloys, some of which are reproduced in Fig.…”

Modified Absorption and Emission Properties Leading to Intriguing Applications in Plasmonic–Excitonic Nanostructures

“…Figure 8d depicts the presence of diffraction peaks corresponding to Au, Pt, and Ni elements and confirms the existence of Au, Pt, and PtNi alloyed NPs on CdS nanoplate surface. [ 155 ] The slight shift in XRD peaks of these nanocrystals as compared to their bulk counterpart can be attributed to the generation of internal stress in synthesized nanocrystals. Additionally, the molar ratios of Pt:Ni (4.3:1) have been evaluated using XRD spectra which match well with the results extracted from EDX analysis (4.2:1).…”