Other Applications - Hierarchical Nanostructures for Energy Devices - page 286

conditions. They observed the ability of the nanowire connectors to bind
strongly even under lubricating conditions, such as a mineral oil, by van der
Waals interactions. The superhydrophobic surface of the nanowire con-
nectors enables the wet, self-cleaning of contaminant particles from the
surface, similar to the lotus effect. In addition, they examined the effect of
nanowire length on the shear adhesion strength, repeated usability, and
robustness of the connectors, all critical properties for applications that
require reversible binding of components.

d n 3 r 4 n g | 8

12.3 Summary
Hierarchical nanostructured electrical devices have shown dramatic
performance enhancement. However, the application of hierarchical nano-
structures is not just restricted to electronic devices. The performance
enhancement could be attributed to the structural functionality of the
hierarchical structuring, which cannot be observed in thin films or bulk
material based devices. In the preceding chapters, various hierarchical
nanostructures for ecient energy consumption electronics applications
were discussed. Among the biggest electronics using nanostructures are
displays (Chapter 10) and sensors (Chapter 11). In this chapter, we discussed
additional applications of hierarchical nanostructures in (1) highly ecient
energy consumption devices including transparent conductors, highly
flexible and stretchable electrodes, light emitting diodes, and (2) mechanical
hierarchical nanostructures, for example, for superhydrophobic and self-
cleaning surfaces, pool boiling enhancement for more ecient heat transfer,
and gecko-inspired adhesives. As long as the surface area or surface
characteristics are considered as important factors in enhancing the func-
tionality of the devices, applying hierarchical nanostructures is one of the
most powerful and promising approaches with a very high degree of design
freedom. More diverse applications of hierarchical nanostructures in
broader fields will be easy to find in the near future.

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