Biofouling is a worldwide problem that leads to severe deterioration after a substrate comes into contact with seawater. 

Traditional polymers and other antifouling coatings suffer from poor mechanical and chemical stability, which diminishes the antibacterial and antibiofouling performance upon progression of usage time.   

A research group led by Prof. TANG Yongbing and his team members (Dr. WANG Tao, HUANG Lei et al.) collaborated with Prof. ZHAO Ying from the Shenzhen Institutes of Advanced Technology (SIAT) of the Chinese Academy of Sciences developed a biomimetic diamond film, which simultaneously achieved superhydrophobicity, self-cleaning, antibacterial efficacy, antibiofouling, mechanical robustness and chemical stability.    

Researchers inspired by the micro- and nano-structures on the taro and lotus leaves, creatively designed the hierarchical structured diamond film and synthesized it via a novel bottom-up strategy based on hot-filament chemical vapor deposition (HFCVD) and two-step self-assembly seeding processes. 

Moreover, the structured diamond coatings were successfully constructed on various commercial substrates, include alloys, silicon, quartz glass, and ceramics, with large scale and complex geometries. The experiments showed that the micro- and nanometer sized hierarchical diamond surfaces has inherently superhydrophobic ability, which could repel microbial adhesion either. 

More notably, the biomimetic hierarchical diamond coatings reduced bacteria attachment by 90-99% and when stayed in the marine environment, this films reduced the adhesion of green algae by more than 95%.  

Even after long-term immersion in seawater, the antibacterial efficacy was still maintained, and meantime the wear resistance of the proposed film was 20 times enhanced than bare commercial substrates.  

The study entitled “Robust Biomimetic Hierarchical Diamond Architecture with Self-cleaning, Antibacterial, and Antibiofouling Surface” was published in ACS Applied Materials & Interfaces. 

Figure. (a-c) SEM surface and cross-sectional morphology and wettability (inset) of the hierarchical diamond film. (d) Fluorescence micrographs of E. coli after 24 h incubation on uncoated control and hierarchical structured diamond film. (e) Schematic illustration of repelling bacteria and all green algae on the structured diamond film. (f) Images and fluorescence micrographs of control (bare glass) and structured diamond film after 14 days immersion in an ecosystem of green algae in seawater. (Image by SIAT)

Media Contact: 
ZHANG Xiaomin 
Email: xm.zhang@siat.ac.cn