Preparation and hydrophobicities of biomorphic ZnO based on carbon derived from indicalamus leaf template

Abstract

Some plant leaves possess a superhydrophobicity because of the exclusive structures on their surfaces. Many methods were developed to imitate the leaf structures in order to obtain the superhydrophobic ZnO. However, it is difficult to simulate the natural complex structures through the traditional methods. In the present study, we used an indicalamus leaf as a template to fabricate a superhydrophobic biomorphic ZnO on a carbon substrate (ZnO/C). First, a carbon substrate with a leaf microstructure was obtained by sintering an indicalamus leaf in argon. The biomorphic ZnO/C was then obtained by immersing this carbon substrate into a Zn(NO₃)₂ solution and again sintering it. This ZnO/C exhibited superhydrophobicity after it was modified with fluorine silane. The water contact angle of the resulting product was 163°, which is similar to that of the indicalamus leaf (159°) and is much higher than that of smooth carbon covered with the same fluorine silane (114°).

Keywords:

• Plant leaf
• ZnO
• Surface
• Superhydrophobicity
• Sintering

The authors wish to express thanks to the National Natural Science Foundation of China (grant no. 51002077), the National Innovative Experiment Program of Undergraduated Students and the Foundation of ‘Zijin Star’ of ‘Excellence Program’ of NJUST.