Synthesis of twisted carbon fibres comprised of four intertwined helical strands

NiSO₄/Al₂O₃ was reacted with H₂ and C₂H₂ in a fluidised-bed reactor at 650 °C to form Ni/Al₂O₃ and H₂S. The Ni catalyst became coated with a moderately graphitised (0.6 I_D/I_G ratio) carbonaceous product containing twisted carbon fibres, 200-500 nm in diameter and up to 27 μm in length. The fibres are comprised of four intertwined helical strands and are a unique carbon morphology. Their growth pattern and surface morphology is attributed to differing carbon extrusion speeds from the faces of the polycrystalline Ni catalyst particles that have been modified by H₂S.