Orderly evolution in the morphology of the anode deposit in hydrogen arc discharge

A layer of carbonaceous deposit with spectacular morphologies was obtained on the anode surface in a hydrogen DC arc-discharge. Pure graphite rods were used in the synthesis process without use of catalytic materials. Along the rod, the deposit product presented many different morphologies such as nanofibers, microfibers, pillars and trees, and was approximately divided into five regions with distinct features. The temperature gradient along the anode was thought to be responsible for the orderly change in deposit morphology.