PNNL

Abstract

Thermocatalytic decomposition (TCD) of methane provides opportunities for hydrogen production with no emission of carbon dioxide. However high value carbon products need to be produced for economic deployment of TCD. In this review, we re-evaluate literature data in catalyst development, and propose fundamental correlations between catalyst characteristics and catalytic stability, properties of carbon products. In the first part, growth mechanisms for carbon nanotubes (CNT) using state-of-the art chemical vapor deposition (CVD) are reviewed to catalog the effects of intrinsic catalyst characteristics, interaction between catalysts and carbon sources, interaction between metal particles and supports, and metal particle sizes on carbon growth. In the second part, representative developments in mono-, bi- and tri-metallic Ni catalysts are highlighted. We present kinetic analysis of reactions catalyzed by mono-metallic Ni catalysts, which generates a correlation between metal particle size and catalyst stability.