In early 1998, the Center Of Super-Diamond and Advanced Films (COSDAF) was launched as a City University Research Center focusing on nanomaterials and nanotechnology. COSDAF brings together a number of academic staff with multi-disciplinary expertise from different departments with research interests in semiconductor nanomaterials, nanoorganic light-emitting displays, diamond and advanced nanocoatings. COSDAF also fosters collaboration with various high-technology local industries, and provides training and facilities to research staff and students.
A paper entitled “Ultralarge elastic deformation of nanoscale diamond”, co-authored by Prof. Wenjun Zhang and Dr. Muk Fung Yuen (MSE & COSDAF), Dr. Yang Lu, Amit Banerjee, Dr. Hongti Zhang, Jiabin Liu, Prof. Jian Lu (MBE) from CityU, and colleagues from Massachusetts Institute of Technology (MIT, US), Institute for Basic Science (IBS, Korea), Ulsan National Institute of Science and Technology (UNIST, Korea), and Nanyang Technological University (NTU, Singapore) et al., has been published by Science. This paper reports for the first time ultralarge, fully reversible elastic deformation of nanoscale (~300 nanometers) single-crystalline and polycrystalline diamond needles. For single-crystalline diamond, the maximum tensile strains (up to 9%) approached the theoretical elastic limit, and the corresponding maximum tensile stress reached ~89 to 98 gigapascals. After combining systematic computational simulations and characterization of pre- and postdeformation structural features, the concurrent high strength and large elastic strain are ascribed to the paucity of defects in the small-volume diamond nanoneedles and to the relatively smooth surfaces compared with those of microscale and larger specimens. Adding to the applications of diamond nanostructures in field electron emission, electrochemical analysis, bioimaging, biosensing, and intracellular delivery of a broad range of molecules and materials including antibodies and DNAs, the new discovery of the extraordinary flexibility and elasticity of nanostructured diamond offers the potential for new applications of diamond nanostructures through their optimized structure design, e.g., nanomechanical engineering, photonics, and optoelectronics.