The Synthesis of Carbon Nanotube on Activated Carbon

The Synthesis of Carbon Nanotube on Activated Carbon Prof. Dr. Sharifah Bee AbdHamid, ImranSyakirMohamad, Norli Abdullah, Ali Rinaldi Combinatorial Technology & Catalysis Research Centre (COMBICAT), Institute of Postgraduate Studies, University of Malaya, 50603 Kuala Lumpur, Malaysia.

Introduction • Why Activated Carbon? • Cheap and abundant resources • High thermal stability • Why Carbon-Carbon composites? • A new trend in catalysis; metal-free catalyst by exploiting the broad chemical functionality of carbon. • Carbon nanotube exhibit excellent activity and long term stability • However due to the compaction of CNTs bundle, it gives severe technical difficulties • Thus immobilizing CNTs on carbon supports (to avoid chemical discontunities) is a promissing solution

Experimental Substrate (AC) Washing (removes impurities; eg: Al, Si, Fe, K) CNT Nanocarbon Growth (Thermal-CVD) Impregnation • Calcination: 250oC, 5%O2 in N2 • Reduction : 300oC, 5%H2 in N2 • Growth : 550oC, 600oC, 700oC, 850oC Characterization • Compositional analysis (XRD) • Morphology/Structure analysis (SEM, HRTEM) • Texture/Surface Area analysis (BET) • Thermal Gravimetric Analysis

Hierarchically structured carbon One chemical element Strong interaction Super adsorption properties Schematic Concept Ni/AC catalyst Activated carbon Carbon from nature source Impregnation reduction Activation Ni particles Palm kernel shell CVD method C2H4→ C + H2 CNFs/AC composite

Image 200nm Growth inside pore and, on the surface of AC support 2µm 500nm 200nm Activated carbon support

Result & Discussion • Ni particle on activated carbon support Ni catalyst Activated carbon support • The reduced-FFT d spacings measurements indicate the sample is fully reduced to Ni0

Result & Discussion • Microstructure • by increasing the temperature growth; • Catalyst transform from solid to liquid-like behavior • different carbon diffusion in the catalyst • catalyst particle size also increase 550oC 600oC 700oC 850oC

Hysterisis CNF Hysterisis CNT Result & Discussion • Textural properties CNF CNT

Increasing temperature, better graphitization • poor graphitic arrangement Result & Discussion • Microstructure of the Carbon

Result & Discussion • Growth mode in the CNT/AC composite • strong metal-support interactions yield base-growth mode • weak metal-support interactions yield tip-growth mode • the activated carbon is chemically non uniform

Result & Discussion • Growth in fluidized reactor Static furnace • Advantages; • useful for bulk application Rotating furnace

Conclusion • Carbon nanotube has been successfully synthesized by Ni catalyst supported on activated carbon. • The CNF/CNT composition and morphology can be controlled by varying the temperature and fluidization of the catalyst support system during growth.

Carbon Team Thank You..

The Synthesis of Carbon Nanotube on Activated Carbon