Macroscopic carbon nanofibers for use as photocatalyst support

To reduce the drawbacks related to the use of powders or immobilized catalysts in gas- and liquid-phase applications, a new material for the use as photocatalyst support was obtained by chemical vapor decomposition at 700 °C of an ethane-hydrogen mixture over a woven glass microfiber supported nickel catalyst, consequently leading to carbon nanofibers with macroscopic shaping, consisting in woven glass microfibers supporting a dense network of entangled 40 nm diameter carbon nanofibers. This material could be directly used after synthesis without any subsequent purification treatment due to the high yield and totally selective carbon nanofiber production. This shape memory design results in the direct use of the carbon nanofiber-woven glass microfiber composite as support without any post-synthesis shaping. The presence of hydrophilic oxygenated groups located at the outer surface of the carbon nanofibers allowed the sol-gel preparation of a woven glass microfiber-carbon nanofiber supported TiO2 (20 wt.%) catalyst, using tetraisopropoxide as precursor. This new photocatalyst was totally stable under UV irradiation.