Author/Authors :
Indrek Tallo، نويسنده , , Thomas Thomberg، نويسنده , , Ky?sti Kontturi، نويسنده , , Alar J?nes، نويسنده , , Enn Lust، نويسنده ,
Abstract :
Nanostructured carbide-derived carbons were synthesized from α-tungsten carbide (WC-CDC) powder via gas phase chlorination within the temperature range from 700 to 1100 °C. Analysis of X-ray diffraction results showed that WC-CDC are mainly amorphous consisting of relatively small graphitic crystallites and the apparent crystallite size along the a- and c-directions of graphite structure La ≈ 4 nm and Lc ≈ 1.5 nm were calculated. The first-order Raman spectra showed the graphite-like absorption peak at ∼1590 cm−1 and the disorder-induced peak at ∼1350 cm−1. The low-temperature N2 sorption experiments were performed and a specific micropore surface area up to 1550 m2 g−1 and total pore volume up to 0.89 cm3 g−1 were obtained for WC-CDC synthesized at T = 1100 °C. High-resolution transmission electron microscopy and electron energy loss spectroscopy studies revealed that WC-CDC prepared at 800 °C correspond to the highly disordered carbon material but WC-CDC prepared at 1100 °C showed partial graphitization.