1. Nanomechanics with nanotubrs and fullerene-like WS2 (MoS2)
R. Tenne
Department of Materials and Interfaces, Weizmann Institute, Rehovot
Cyclamen in Jerusalem mountains
Anemone flowers in the north Negev desert
Minerva and Krupp Foundations, GIF, BSF, ISF, Bikura, IME (Kamin), IMoST
“NanoMaterials, Ltd.”, H. Perlman, Waltcher, Gurwin and Horowitz Foundations,
EU (ERC, PoC, “AddNano”, “COINAPO”, “MoWSeS”, “MEDIF-2”), INNI, NEDO&TTRF-Japan
Courtesy of Prof. G. Seifert, Dr. A. Enyashin, TU Dresden

2. R. Dunin-Borkowski, Oxford U
Multiwall WS2 nanotubes (type I)
Type 1: Spontaneous nucleation and growth
Thin nanotubes (20-40 nm)
R. Dunin-Borkowski, Oxford U
1996
R. Rosentsveig et al., Chem. Mater. 14, 471 (2002)
G. Seifert, Th. Köhller, and R. Tenne, J. Phys. Chem. B 106, 2497 (2002)

3. Plasma assisted synthesis of 1-to 3-wall WS2 nanotubes
electromagnet
for mechanical vibration
glass window
with copper coil
vibrating sample holder
reactor
chamber
Argon
Vacuum pump
Matching-network
RF-Generator
V. Brüser, R. Popovitz-Biro, A. Albu-Yaron, T. Lorenz, G. Seifert, R. Tenne and A. Zak, Inorganics 2, (2014)

4. Tribological measurements of IF-MoS2 nanoparticles
Lubricant
Calculated
Hertzian
Wear Scar (µm)
Pin Wear Scar
Diameter (µm)
Flat Wear Scar
PAO oil 92
200
180
2H-MoS2
190
175
IF-WS2
160
130
IF-MoS2
150
100
J. Tannous and F. Dassenoy, Ecole Centrale de Lyon, France
R. Rosentsveig et al., Tribol. Lett., 36, 175 (2009), and J. Mater. Chem., 19, 4368 (2009)

5. On the mechanism of lubrication of IF nanoparticles
0.6 GPa
1.0 GPa
Rolling friction
1.2 GPa
Exfoliation and transfer
O. Tevet, P. Von-Huth, R. Popovitz-Biro, R. Rosentsveig, H. D. Wagner and R. Tenne,
PNAS 108, (2011)

6. Summary of the mechanical properties of IF NP
O. Tevet, P. Von-Huth, R. Popovitz-Biro, R. Rosentsveig, H. D. Wagner and R. Tenne, PNAS 108, (2011)

7. Bending of multiwall WS2 (MoS2) Nanotubes
experiment
δ - the nanotube’s deflection
F - that applied force
L - the nanotube’s length
E - the Young's modulus
I – the geometrical moment of inertia
fs – geometrical constant (10/9)
G – the shear (sliding) modulus
A – area of cross section
Timoshenko Eq.
G=2.0±1.1 GPa
3-4.1 GPa (DFTB Theory)
E= 160 GPa
DFTB calculations for shear
(sliding) of two MoS2 walls
I. Kaplan-Ashiri, S.R. Cohen, Y. Wang, N. Apter, Y. Wang, G. Seifert, H.D. Wagner, R. Tenne,
J. Phys. Chem. C, 111, 8432 (2007)

8. SEM view of a buckling of an individual WS2 nanotube
E= GPa
Kaplan-Ashiri, K. Gartsman, H.D. Wagner, V. Ivanovskya, T. Heine, G. Seifert, and R. Tenne, PNAS, 103, 523 (2006)
II. D.-M. Tang, C. Nethravathi, X. Wei, M.-S. Wang, N. Kawamoto, Y. Bando, M. Mitome, A. Zak, R. Tenne and D. Golberg, NanoLett. 13, 1034 (2013)

9. Stress-strain curve of a WS2 nanotube from SEM tensile stress experiment
Before…
After…
Tensile strength= GPa
E=160 GPa; 12% elongation
E- Young’s modulus
Telescopic failure
I. Kaplan-Ashiri, K. Gartsman, H.D. Wagner, S.R. Cohen, V. Ivanovskya, T. Heine, G. Seifert, and R. Tenne, PNAS, 103, 523 (2006); M.S. Wang, L.-M. Peng et al., Nano Res. 1, 22 (2008)

10. Nanomechanics of WS2 nanotubes (type I and II)
Type II nanotubes
(A. Zak) curve
Type I-nanotubes
(R. Rosentsveig)-
curve
I. Kaplan-Ashiri et al., PNAS 103, 523 (2006)
D. Golberg, and co-workers, NanoLett. 13, 1034 (2013)

11. Electrospun PMMA fibers
SEM of the electrospun fibers
SEM of the dispersed WS2 nanotubes
C.S. Reddy, A. Zak and E. Zusmann, J. Mater. Chem. 21, (2011)

12. Reinforcement of epoxy resin by WS2 nanotubes
pull-out mechanism
bridging mechanism
E. Zohar, S. Baruch, M. Shneider, H. Dodiuk, S. Kenig, R. Tenne and H.D. Wagner, J. Adhes. Sci. Tech. 25, 1603 (2011)

13. Portland-concrete reinforcement by nanotubes
R. Nadiv, M. Shtein, M. Rafaeli, A. Peled and O. Nadiv, Construction and Building Materials 98 (2015) 112–118 and submitted

14. Advanced Mg alloy nanocomposites reinforced by WS2 nanotubes
Toughness [MPa]
% change
AZ31-4
13.1 -
AZ31INT1-1
38.1
190
AZ31INT1-2
15.3 17
AZ31INT1-3
48.8
272
AZ31INT1-avg.
34.1
160
S.-J. Huang, C.-H. Ho, Y. Feldman and R. Tenne, submitted

15. Pull-out of individual WS2 nanotubes from water (liquids) surfaces
AFM/ESEM
MD-simulation
Pull-out
O. Goldbart, S.R. Cohen, I. Kaplan-Ashiri, A.N. Enyashin, R. Tenne and H.D. Wagner, to be published