1. Department of Materials Science and Engineering; City University of Hong Kong; 83 Tat Chee Avenue Hong Kong SAR China
2. City University of Hong Kong Shenzhen Research Institute; Shenzhen 518057 China
3. Center of Super-Diamond and Advanced Films (COSDAF); City University of Hong Kong; 83 Tat Chee Avenue Hong Kong SAR China
4. Institute for Bioengineering; School of Engineering; University of Edinburgh; Edinburgh UK