Enhanced Low-temperature Catalytic Decomposition Performance of Naphthalene over Hydrothermal Carbon-based Nanomaterials with a Hierarchical Heterostructure

A series of hydrothermal carbon-supported nickel catalysts with an Ageratum conyzoides L.-like superstructure derived from green and sustainable cellulose (Nix/NyHC-SFz) were fabricated by a facile soft template/nitrogen co-directed hydrothermal assembly strategy. The soft template and nitrogen doping into the hydrothermal carbon framework not only dictated specific morphological evolution for creating the architecture with a mesoporous texture but also significantly tuned the electronic properties of the composites with strong metal-support interactions. Benefiting from these unique characteristics as well as systematic control of the experimental conditions, the hierarchical structured Ni-x/NyHC-SFz composites served as promising catalysts with desirable low-temperature tar reforming activity and long-term durability. In particular, the N-0.2/N2HC-SF3 composite exhibited a maximum naphthalene conversion of 87.6%, while the N-0.2/N4HC-SF3 composite demonstrated an optimum H-2 selectivity of 81.2% at a mild temperature of 600 degrees C. For the Ni-0.2/N2HC-SF3 composite, more than 92.8% of the initial naphthalene conversion and 86.5% of initial H-2 selectivity were still retained after 10 consecutive cycles. Given the chemical tunability of both active metal species and precursory carbon sources in this fabrication system, we envisioned that the general design principle of low-cost yet high-performance nonprecious nickel catalysts in this work could be extended to the construction of other biochar-based nanomaterials for specific catalytic applications.

Automated summary

In this study, a series of hydrothermal carbon-supported nickel catalysts with an Ageratum conyzoides L.-like superstructure were fabricated. These hierarchical structured composites exhibited promising low-temperature tar reforming activity and long-term durability, making them potential candidates for catalytic applications.