Templated diamond growth on porous carbon foam decorated with polyvinyl alcohol-nanodiamond composite

Porous and self-standing structures are highly promising as membranes, electrodes, high sensitivity gas sensors, and supercapacitors due to their high surface area and tuneable surface properties. Composition of such materials with a polycrystalline diamond film may provide new functionalities for biological and electrochemical applications. However, the diamond growth on foreign substrates as a pinhole-free continuous thin film is still a not a trivial task. Here, we present a successful templated deposition process of polycrystalline diamond film on reticulated vitreous carbon foam (C-foam). Samples of polyvinyl alcohol (PVA) polymer-nanodiamond (ND) mixtures with various ND concentrations were prepared and characterized by means of optical spectroscopy, Raman spectroscopy, dynamic light scattering, zeta potential and pH measurements. The ND/PVA mixtures are employed for the preparation of diamond film by microwave plasma enhanced chemical vapour deposition process, and the effect of their composition (NDs/PVA ratio) on the nucleation (seed density, clustering) and diamond growth (substrate etching, polymer transformation) is analysed. The nucleation, early-stage of diamond growth and the resulting diamond-coated C-foams are characterized by scanning electron microscopy, atomic force microscopy and Raman spectroscopy. The obtained results underline the importance to tailor the NDs/PVA ratio for a well-defined three-dimensional C-foam coverage with the continuous diamond film.

1) Schematic representation of the interaction of nanodiamonds in PVA polymer, which was subsequently applied to porous carbon foam and subjected to 2) chemical deposition from gas vapor in microwave plasma with linear antennas. 3) Surface morphology of diamond-coated porous carbon foam.

¹Institute of Physics, Czech Academy of Sciences, Cukrovarnická 10, 162 00 Prague 6, Czech Republic
²Faculty of Civil Engineering, Czech Technical University, Thakurova 7, 166 29, Prague 6, Czech Republic
³

KIST Jeonbuk Institute of Advanced Composite Materials, Chudong-ro 92, Bongdong-eup, Wanju-gun Jeonbuk, 55324, South Korea