Growth and optical properties of Cu₂ZnSnS₄ decorated reduced graphene oxide nanocomposites

Abstract

Cu2ZnSnS4 (CZTS) nanoparticles were synthesized by the precursor injection method using oleylamine as a solvent. Preliminary characterization indicated that the synthesized nanoparticles belonged to the kesterite structure with a bulged sphere-like morphology. Reduced graphene oxide (rGO) was synthesized by an improved Hummers method and was used for nanoparticle functionalization. CZTS nanocrystals were decorated on rGO by two different methods. One was oleylamine-based nanoparticle functionalization, and the other was in situ nanoparticle growth. Transmission electron microscopy analysis of CZTS-functionalized rGO showed that the synthesized nanoparticles were uniformly spread on the surface of rGO sheets. Single phase CZTS nanoparticles were grown on rGO without any impurity phase in the in situ growth. Tuned absorption of the pure CZTS was observed by the decoration of CZTS nanoparticles on the surface of rGO in the visible and UV regions.

Cu2ZnSnS4/MoS2-Reduced Graphene Oxide Heterostructure: Nanoscale Interfacial Contact and Enhanced Photocatalytic Hydrogen Generation

“…The G band is related to the in-plane vibration mode of sp2 carbon, while D band demonstrates defective and partially disordered structures of the carbon to sp3 hybrid carbon. All the characteristic Raman bands for CZTS and few-layer MoS 2 can be found at 335, 383, and 409 cm −1 , corresponding to the mode of CZTS and , modes of MoS 2 , respectively434849. The Raman spectrum of CZTS/MoS 2 -rGO heterostructure also reveals the coexistence of all three components with high purity.…”

“…At the same time, the sulfur ions bind to the exposed Mo atoms of MoS 2 and defective sites of rGO through covalent binding42. Upon heating at high temperature, H 2 S is in situ produced and reacts with the metal precursors to form CZTS on the surface of MoS 2 -rGO hybrid43. The co-existence of four constituent elements in CZTS as well as Mo was confirmed by energy dispersive spectroscopy (EDS) and elemental mapping (Figs S2 and S3).…”

“…The Raman spectrum of CZTS/MoS 2 -rGO heterostructure also reveals the coexistence of all three components with high purity. The heating in oleylamine at high temperature (280 °C) is believed to induce the reduction of graphene oxide to rGO43. The optical properties of heterostructure are also affected by the formation of nanoscale interfacial contact between two different materials.…”

In situ Growth of Phase‐Controlled Nickel Sulfide Nanostructures on Reduced Graphene Oxide Nanosheets : A Improved Cost‐effective Catalyst for 4‐Nitrophenol Reduction

“…The synthesized GO was first characterized by XRD. We previously investigated the effect of oleylamine on the reduction ability of GO . A separate experiment was carried out to confirm reduction with oleylamine.…”

Graphene‐Based Hybrid Functional Materials

“…Then the assembly may be deposited onto a substrate by different techniques. For instance, Hayakawa and co‐workers [ 21 ] prepared a hybrid of rGO and Cu 2 ZnSnS 4 by both ex situ and in situ methods. In the first case, the previously synthesized Cu 2 ZnSnS 4 NPs were mixed with rGO in cyclohexane, and the formation of the hybrid was favored by the addition of oleylamine as surfactant and by ultrasonicating the dispersion.…”