Nano crystalline diamond

Nano crystalline diamond has a wide potential window of water stability, similar to that of diamond [29]. The current peak at +1.7 V vs. SHE, often found in voltammograms of polycrystalline diamond, is absent from these films. Yoo and co-workers reported that tetrahedral amorphous carbon, ta-C N, had a chemical stability similar to that of boron-doped diamond and a wider potential window for water stability [30]. The ta-C N electrodes were more catalytic for electron-transfer reactions than diamond electrodes, e.g., they exhibited reversible behavior with outer-sphere couples. These properties are believed to arise from the presence of sp2 carbon and nitrogen within the amorphous structure. 

It is commonly recognized that a comprehensive understanding of the properties of a new material is an essential prerequisite to finding its new applications. In this respect, the study of ultrafine diamond is incomplete and its properties remain to be fully elucidated. For example, the nature of the surface functional groups and the method of their modification the nature of the agglomeration of ultrafine crystallites and effective methods of de-agglomeration to prepare mono-dispersed suspension the crystalline and surface structures of the nano-scaled diamond, etc., are appropriate subjects of research An efficient method for the determination of particle size distributions and structures of nano-sized particles in suspension is very important, and is worth developing in the near future. 

Figure 12. Population density (A) and adhesion area (B) of osteoblast-like MG 63 cells on day 2 after seeding on tissue culture polystyrene dish (TCPS). carbon fibrereinforced carbon composites (CFRC) and CFRC coated with a fullerene layer (CFRC+full). C Growth curves of MG 63 cells on a terpolymer of polytetrafluoroethylene. poljcvinyldifluoride and polypropylene (Ter), terpolymer mixed with 4 wt. % of single-wall carbon nanohorns (SWNH) or 4 wt.% of high crystalline electric arc multi-wall nanotubes (MWNT-A). D Growth curves of MG 63 cells on TCPS. a nanostructured diamond layer (Nano) and a layer with hierarchically organized micro-and nanostructure (Micro-Nano). Mean S.E.M. from 4-12 measurements. ANOVA. Student-Newman-Keuls method. Statistical significance TCPS. CFRC. Ter p<0.05 compared to the values on tissue culture polystyrene, pure CFRC and pure terpolymer [23].

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