Diamond nanofeathers

• Published in: Diamond and related materials 2019-01, Vol.91 (C), p.165-172
• Main Authors: Zeng, Hongjun, Moldovan, Nicolaie, Catausan, Grace
• Format: Article
• Language: English
• Subjects: Diamond films; Diamonds; Electrochemical analysis; Fractal geometry; Grain boundaries; High aspect ratio; Materials Science; Nanostructure; Photovoltaic cells; Physics; Pore size; Porosity; Raman spectra; Solar cells
• ISSN: 0925-9635; 1879-0062
• DOI: 10.1016/j.diamond.2018.11.016

This paper reports a special diamond nanostructure which we call diamond nanofeathers (DNFs). The nanostructure was discovered after electrochemically etching doped nanocrystalline diamond (NCD) films. With high resolution SEM, we have repeatedly observed highly porous, fractal-like geometry with “shafts”, “barbs” and “barbules” of the DNFs. A DNF has very high aspect ratio, with a height comparable to the thickness of the etched diamond film and a lateral size as small as several nanometers. This diamond nanostructure seems not to belong to either conventionally defined NCD or ultrananocrystalline diamond (UNCD). The Raman spectra tell that after the electrochemical etch, the DNFs have lower signals from the grain boundaries, compared with the Raman spectra before the etch, which suggests the pores of the DNFs was related with mass loss from the grain boundaries. Preliminary electrochemical characterization has observed more than 300× capacitance increase after the DNFs are fabricated out of a NCD film. With the specific pore size and the ease of fabrication, the DNFs could be a great material choice for supercapacitors, batteries, sensors, and solar cells etc. [Display omitted] •New diamond nanostructure - diamond nanofeather from fabrication to characterization•Diamond nanofeathers have fractal-like geometry with “shafts”, “barbs” and “barbules”.•Diamond nanofeather is neither conventionally NCD nor UNCD.•Diamond nanofeather could have impact on energy storage, sensors and solar cells.