Atomic force microscopy and thermodynamics on taro, a self-cleaning plant leaf

Applied Physics Letters

Volumn 95, Issue 3, 2009, Pages

  Huger E ^a   Rothe, H ^a   Frant, M ^a   Grohmann, S ^a   Hildebrand, G ^a   Liefeith, K ^a  

^a Institute for Bioprocessing and Analytical Measurement Techniques   (Germany)

Author keywords

[No Author keywords available]

Indexed keywords

ATOMIC FORCE MICROSCOPES; CLEANING PLANTS; COLOCASIA; HIERARCHICAL STRUCTURES; INTERACTION STRENGTH; NELUMBO NUCIFERA; SELF-CLEANING PROPERTIES; SELF-CLEANING SURFACES; SUPERHYDROPHOBIC STATE; THERMODYNAMIC CALCULATIONS; UNDRIED; WATER DROPLETS;

ATOMIC FORCE MICROSCOPY; ATOMS; MORPHOLOGY; THERMODYNAMICS;

OPTIMIZATION;

EID: 67651251294     PISSN: 00036951     EISSN: None     Source Type: Journal    
DOI: 10.1063/1.3184582     Document Type: Article

References (16)

1. P. Wagner, R. Furstner, W. Barthlott, and C. Neinhuis, J. Exp. Bot. 0022-0957 54, 1295 (2003). 10.1093/jxb/erg127 (Pubitemid 36412926)
2. A. Solga, Z. Cerman, B. F. Striffler, M. Spaeth, and W. Barthlott, Bions. Biomim. 2, S126 (2007). 10.1088/1748-3182/2/4/S02 (Pubitemid 350179163)
3. K. Koch, A. J. Schulte, A. Fischer, S. N. Gorb, and W. Barthlott, Bions. Biomim. 3, 046002 (2008). 10.1088/1748-3182/3/4/046002
4. K. Koch and H. -J. Ensikat, Micron 0968-4328 39, 759 (2008). 10.1016/j.micron.2007.11.010
5. K. Koch, B. Bhushan, and W. Barthlott, Soft Matter 1744-683X 4, 1943 (2008). 10.1039/b804854a
6. Z. Burton and B. Bhushan, Ultramicroscopy 0304-3991 106, 709 (2006). 10.1016/j.ultramic.2005.10.007 (Pubitemid 43994316)
7. B. Bhushan and Y. C. Jung, Nanotechnology 0957-4484 17, 2758 (2006). 10.1088/0957-4484/17/11/008 (Pubitemid 43814926)
8. R. Garcia, R. Magerle, and R. Perez, Nature Mater. 1476-1122 6, 405 (2007). 10.1038/nmat1925 (Pubitemid 46869990)
9. B. Bhushan and Y. C. Jung, J. Phys.: Condens. Matter 0953-8984 20, 225010 (2008). 10.1088/0953-8984/20/22/225010 (Pubitemid 351763573)
10. P. -H. Puech, K. Poole, D. Knebel, and D. J. Muller, Ultramicroscopy 0304-3991 106, 637 (2006). 10.1016/j.ultramic.2005.08.003 (Pubitemid 43994307)
11. H. -J. Ensikat and W. Barthlott, J. Microsc. 0022-2720 172, 195 (1993).
12. The AFM measurements on superhydrophobic leaf surfaces were rather challenging. Frequently a strong lateral deflection of the laser signal up to overange photodiode signal-appears during the AFM scan probably caused by lateral bending and torsion of the cantilever. Therefore the AFM scan movement often stopped. This appears more frequently for scans in air and also in liquids for the first period of time after the leaves were immersed in the liquid. We observed that the submersion time needed for a successful scan was dependent on the microstructure of the leaf surfaces. Dried Colocasia esculenta with collapsed papillae needed 2 hours of submersion before a reasonable scan could be measured. Noncollapsed papillae could be reasonably scanned only after approximately 20 h of preliminary water submersion. As recently pointed out (Ref.), the high dewetting ability of superhydrophobic plant leaves can be transformed to a wetting state by soaking the leaves in water for some hours. This shows that successful AFM scans can be performed once the plant surface is wetted thoroughly.
13. J. Zhang, X. Sheng, and L. Jiang, Langmuir 0743-7463 25, 1371 (2009). 10.1021/la8024233
14. A. Marmur, Langmuir 0743-7463 19, 8343 (2003). 10.1021/la0344682
15. B. Bhushan, K. Koch, and Y. C. Jung, Appl. Phys. Lett. 0003-6951 93, 093101 (2008). 10.1063/1.2976635
16. The intrinsic contact angle of the Colocasia esculenta leaf was estimated (Refs.) from calculation to range between 126° and 96°. The contact angle of a water droplet against paraffin wax was reported (Ref.) to be 104°. We present calculations at an intrinsic contact angle of 100°. There the wetting state for the hierarchical structure is fully unstable.