Statistical patterns in high-throughput growth of single-wall carbon nanotubes from Co/Pt/Mo ternary catalysts

Designed alloy catalysts have shown promise in structure-controlled growth of single-wall carbon nanotubes (SWCNTs). However, due to the high-dimensional growth parameter space and low efficiency of the conven-tional trial-and-error optimizing approach, it is still challenging to explore and to establish the relations between catalyst compositions and the structure of SWCNTs. Here, we present a high-throughput strategy to investigate the statistical patterns in catalyst activity and selective growth of SWCNTs using Co/Pt/Mo ternary catalysts. Statistical analysis reveals that in the Co/Pt/Mo ternary diagram, there is an active region in the Co-rich Co-Mo corner to grow SWCNTs with high yield (>= 25 tubes/mu m2) and high quality (IG/ID >= 40). Enriched semi-conducting (s-) SWCNTs with a purity higher than 90% were obtained along the boundary of the high yield region, near the Co-Pt axis. The statistical patterns of the yield, quality and selectivity are associated with the alloy composition, revealing a negative correlation between the yield and enrichment of s-SWCNTs. High -resolution transmission electron microscope characterization shows that a Co-Pt alloy catalyst with a uniform size distribution facilitates the s-SWCNT enrichment. And the separate phases of a Co-Mo/Co catalyst stabilize the active Co phase, leading to long catalyst lifetime and high yield of SWCNTs.

Automated summary

Designed alloy catalysts have shown promise in structure-controlled growth of single-wall carbon nanotubes (SWCNTs). However, it is still challenging to explore and establish the relations between catalyst compositions and the structure of SWCNTs due to the high-dimensional growth parameter space and low efficiency of the conventional trial-and-error optimizing approach. In this study, a high-throughput strategy using Co/Pt/Mo ternary catalysts is presented to investigate the statistical patterns in catalyst activity and selective growth of SWCNTs, revealing the negative correlation between the yield and enrichment of semi-conducting SWCNTs. A Co-Pt alloy catalyst with a uniform size distribution facilitates the enrichment of semi-conducting SWCNTs, while the separate phases of a Co-Mo/Co catalyst stabilize the active Co phase, leading to long lifetime and high yield of SWCNTs.