Liquid-Phase Exfoliation of Germanane Based on Hansen Solubility Parameters

Abstract

Two-dimensional (2D) materials combine the collective advantages of individual building blocks and synergistic properties and have spurred great interest as a new paradigm in materials science. For the mass production of these materials, large-scale exfoliations are the main production route; but, recent approaches in the liquid-phase exfoliation are based on empirical trial and error strategies. This study aims to propose a method to determine the suitable solvents for efficiently exfoliating germanane (GeH) and the optimal solvent removal conditions at moderate temperatures using Hansen solubility parameters. We confirm the presence of GeH nanosheets using atomic force microscopy. The proposed method revealed that GeH can be efficiently dispersed in 1,3-dioxolane and can be deposited as individual sheets, which have the thickness of 3−4 nm and the lateral size in the range of a few micrometers.

2D Elemental Nanomaterials Beyond Graphene

“…Bulk germanane is a layered material with a significant van der Waals gap of 5.9 Å between the layers. It can easily be exfoliated down to a mono‐layer germanane . Germanane exhibits a buckled structure with a mixed sp 2 ‐ sp 3 hybridization of Ge atoms.…”

A review on graphene strain sensors based on fiber assemblies

“…Graphene has been widely used as nanofillers for strain sensors due to its good mechanical and electrical property (stress of 130 GPa, conductivity of 7200 S m) [26][27][28][29][30]. At present, there are three main methods for graphene preparation: Chemical vapor deposition (CVD) [31], Redox Process [32] and Liquid phase exfoliation (LPE) [33][34][35]. Among them, the redox method can also be regarded as a special way of LPE.…”

Rapid and Low‐Temperature Salt‐Templated Production of 2D Metal Oxide/Oxychloride/Hydroxide

“…Recently, 2D materials such as graphene, metal oxide, metal carbide, metal dichalcogenides, and pure metal, have played an important role in electronics, sensors, optics, electrocatalysis, and energy storage, owing to the unique atomic thin feature, high specific surface area, and large aspect ratios. Many methods for the preparation of 2D materials have been explored, including liquid phase exfoliation (LPE), mechanical repeated folding and calendaring (RFC), chemical vapor deposition (CVD) or van der Waals epitaxy approach, and salt‐templated or molten salt‐templated method (MSM) . The liquid phase exfoliation method is confined to the layered materials (graphite, MoS 2 , and antimony), in which the layers are connected by van der Waals force.…”

“…It is worth to note that the salt‐templated method has been further developed by molten salt‐templated method, which takes a very short time (just few minutes) to synthesis 2D metal oxides and hydroxides. Whereas, the short time reaction needs a relative high temperature (≈350 °C) . Thus, it is of crucial meaningful to develop a high‐yield, rapid, and low‐temperature method to synthesize 2D materials.…”

“…Whereas, the short time reaction needs a relative high temperature (≈350 °C). [31] Thus, it is of crucial meaningful to develop a high-yield, rapid, and low-temperature method to synthesize 2D materials. Different from other metal chloride hydrates (FeCl 3 ·6H 2 O, AlCl 3 ·6H 2 O, CuCl 2 ·2H 2 O, and SnCl 2 ·4H 2 O), cobalt dichloride hexahydrates (CoCl 2 ·6H 2 O) is a typical 2D compound possessing the layered structure and low melting point (86 °C), which possess monoclinic structure with space group C2/m (a = 8.898, b = 7.066, c = 6.644, α = 90.0, β = 97.25, and γ = 90.0 (PDF#29-0466)).…”