TU Delft Centrifuge Calculator: 2D Nanosheets

This version of the calculator is for 2D nanosheets.

1. Particle Properties

particle density (kg/m³)

scaling prefactor (nm)

scaling exponent

single-layer thickness (nm)

Reference values for different 2D materials:

Material type	Scaling prefactor (nm)	Scaling exponent	Single-layer thickness (nm)
Graphene	55.1	0.97	0.3
BN	19.1	1.33	0.3
WS₂	12.7	1.43	0.7
MoS₂	11.4	1.43	0.65

Note: The values of scaling prefactors and exponents in this table are estimated based on Figure 2(d) in [1].

How to extract scaling prefactor and exponent:

From AFM measurement, a plot like the one below can be made which shows the correlation between the lateral size (L) and number of layer (N) of the nanosheets [2].

The axes in the plot are in log-log scale. By a linear fitting of the data (the red line in the plot), a power law relationship between L and N can be established: L=kN^a. Here, k is the scaling prefactor with dimension of length, and a is the scaling exponent without dimension.

2. Solvent Properties

solvent density (kg/m³)

dynamic viscosity (Pa s)

3. Geometric Properties of the Centrifuge and Dispersion

rotor radius (mm)

dispersion height (mm)

4. Calculation

Two of the following three parameters have to be input, the other one will be calculated after pressing the corresponding "Calculate" button.

Cut-off nanosheet layer number means the layer number of the thickest nanosheet left in the supernatant after centrifugation.

Cut-off nanosheet layer number

Centrifugation time (min)

Revolutions per minute (RPM)

The formula on which this calculator is based can be found in [3]. If you use this calculator in a publication, please cite this paper.

[1] Ogilvie et al., 2D Mater. 2019, 6, 031002.

[2] Chacham et al., ACS Appl. Nano Mater. 2020, 3, 12095-12105.

[3] Li et al., to be submitted.