Synthesis of polypyrrole on nanodiamonds with hydrogenated and oxidized surfaces

Abstract

Composite nanoparticles of detonation nanodiamond (DND) and polypyrrole (PPy) were produced in colloidal solution and on surfaces by wet chemical process. Changes of vibrational bands (in particular > CÀ À À ÀO and C-H) in Fourier-transform infrared spectroscopy revealed the DND/PPy composite formation and tight interaction of PPy with hydrogenated DND (H-DND) and oxidized DND (O-DND). Atomic force microscopy showed uniform PPy coating but different PPy thickness on H-DND (7.0 nm) and O-DND (3.5 nm). These results suggest different bonding nature and arrangement of PPy on H-DND and O-DND surfaces.

Nanodiamond surface chemistry controls assembly of polypyrrole and generation of photovoltage

“…PPy thicknesses on O-DND and poly-DND appeared to be smaller than estimated in our previous work 49 . This might be due to the more accurate particle height evaluation procedure in this work by grain analysis using the watershed method (see the Experimental section) compared to particle height estimation via roughness analysis in 49 , where mean particle height was determined as the difference between the roughness of nucleated and exposed parts of a substrate. However, different particle height evaluation methods lead to the same trend in PPy thickness which is maximum on poly-DND and 2–3 times less on O-DND.…”

“…However, different particle height evaluation methods lead to the same trend in PPy thickness which is maximum on poly-DND and 2–3 times less on O-DND. Because of the same Py polymerization conditions for all types of DND particles, different PPy thickness on poly-, H- and O-DND, as was discussed in 49 , can be explained by the different PPy chains arrangement relative to the different types of DNDs. The different PPy arrangement might be caused by the different bonding nature between PPy and DNDs of different surface terminations, which is the matter of our further investigation by spectroscopic techniques.…”

“…Mean heights of composite and reference DNDs particles were calculated. The PPy layer thickness on DNDs was determined by the formula in 49 .…”

Structural and Electronic Properties of Oxidized and Amorphous Nanodiamond Surfaces with Covalently Grafted Polypyrrole

“…We show that even with amorphous carbon the PPy-ND system retains its qualities. The results thus complement the recent experimental work on the PPy-DND composites, [10] corroborating their potential as an opto-electronically active medium in solar cells.…”

“…[9] Our prior studies with polypyrrole (PPy) organic dye showed experimentally that composites of hydrogenated and oxidized detonation nanodiamonds (DNDs) with PPy were successfully fabricated and evince promising properties for photovoltaic applications. [10] Suitability of PPy for photovoltaic applications was also supported by an observed transfer of photogenerated charge between the bulk diamond and PPy observed by Kelvin force microscopy and optical spectroscopy. [11,12] The most typical ND facets, present both on the synthetic and natural diamonds, are (111) and (100) facets.…”