Transformation of CO₂ to Carbon Nanotubes by Catalytic Chemical Vapor Deposition using a Metal-Supported Hierarchical Zeolite Template

The conversion of CO2 into valuable substances is a topic of great interest in current research. Carbon nanotubes (CNT) have emerged as highly promising materials for CO2 conversion. In this study, we successfully developed a catalyst by loading active transition metals (Fe or Ni) onto hierarchical zeolite for CNT synthesis. Our catalyst demonstrated excellent performance under synthetic conditions. The most favorable CNT was obtained using the 25 wt.% FeHieFAU catalyst, which exhibited a diameter size of 23.1 nm, a CNT yield of 15.4 %, and an I-D/I-G ratio of 0.56, indicating high quality. Additionally, we investigated the beneficial effects of the synthesized CNT by testing their current response. Notably, the current response of the synthesized CNT surpassed that of commercial CNT when using a 0.5 M H2SO4 supporting electrolyte and cyclic voltammetry (V vs. Ag/AgCl). These findings highlight the significant contributions of the small diameter and superior quality of our synthesized pure CNT, which offer potential improvements in current response compared to commercial CNT. This research opens new avenues for utilizing CNT in CO2 conversion and electrochemical applications.