Title : Time-evolving growth of 3D-nanocrystalline carbon from the electro-reduction of acetic acid with in-situ electrodeposited Ag at ambient conditions
Abstract:
Nanocrystalline carbon thin films containing nanodiamond and diamond-C (progressive intermediates in the graphite-to-diamond phase transition) were produced by a low-energy production method, consisting of the in-situ electrochemical reduction of acetic acid/Ag(NO3) using a relatively small negative potential of -1.1 V vs Ag/AgCl at ambient conditions. After applying the negative potential, ultra-thin layer of Ag was firstly deposited and subsequently competitive electrodeposition of Ag and electroreduction of acetic acid resulted in formation of crystalline solid carbon and Ag-C products on the electrodes. A combination of microscopic, structural, and spectroscopic characterization results showed that the Ag-C product layers gradually developed into nanocrystalline carbon films with some large 3D-polyhedra carbon and nanodiamond with average crystallite size ~26 nm as the reaction time increased from 15 to 140 min. The nanocrystalline carbon-film growth rate was calculated to be ca. 8 μm.h−1 without the production of any gas or liquid products.
Audience Take Away:
- Nanocrystalline diamonds (nanodiamonds) are valuable materials for various applications, whereas low-energy synthesis methods have remained a substantial challenge.
- In this work, we reveal the nanocrystalline carbon-containing both nanodiamonds and micron-size diamond-C structures by a concurrently electrochemical reduction of acetic acid with electrodeposition Ag on copper foil substrate at ambient conditions with relatively low negative potential (-1.1 V vs. Ag/AgCl).
- The growth of Ag-C layers developed into nanocrystalline carbon thin films with average nanodiamond crystallite size ~26 nm during 15 - 140 reaction time. Furthermore, large 3D-polyhedra of carbon and diamond-C structures can be observed on the surface electrocatalyst once the reaction time increases.
- The obtained products are unique, and the process allows fast growth rate of nanocrystalline carbon-film at ca. 8 μm.h−1.
