A lotus-leaf-like SiO2 superhydrophobic bamboo surface based on soft lithography

- Lotus-leaf-like microstructure surfaces were built on bamboo surfaces using soft lithography.
- Nano SiO2 can improve the strength, water resistance, and thermal stability of bamboo.
- The lotus-leaf like bamboos can effectively prevent moisture to invasion of bamboos, and improve the dimensional stability.
- It opens up a new way for the researches of functional bamboos and will broaden the application prospects of bamboo.
- It can prolong the bamboos' service life, and alleviate the contradiction between the supply and the demand of timber.

Biological microstructures have been a source of inspiration for scientific researchers and artists. In this paper, the microstructure of the lotus leaf was replicated on the bamboo surfaces by soft lithography, using a fresh lotus leaf as the template and polydimethylsiloxane (PDMS) for a seal. And the hydrophobic monodisperse nano SiO2 microspheres were added to improve the strength, abrasion resistance, and water resistance of the bamboo surfaces. X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) and atomic force microscope (AFM) showed that the lotus-leaf-like bamboo had a polycrystalline surface, and the lotus-leaf-like topography played a very important role in the fabrication of the superhydrophobic surface. The water contact angle (WCA) of lotus-leaf-like bamboo surface was 152.5° with a low hysteresis showing a good superhydrophobic property. The successful preparation of the lotus-leaf-like bamboo provided a new method for researches on the water corrosion resistance of bamboos, and also confirmed the feasibility that hydrophilic surfaces like the bamboo could be achieved with the nanotechnology.

A lotus-leaf-like rough surface was biomimeticly prepared on bamboo surfaces by transfer technology of soft lithography. The fresh lotus leaf and PDMS were as a template and seal. The lotus-leaf-like SiO2 superhydrophobic bamboos could effectively prevent moisture from invading bamboos and improve the dimensional stability, which will broaden the application prospects of bamboo.100