Nitrogen Doped Graphenated Carbon Nanotubes for Electrochemical Reduction of Carbon Dioxide

Electrochemical reduction of atmospheric carbon dioxide with renewable energy has the potential to provide clean fuel to meet the world’s growing energy demands while reducing the global anthropogenic carbon footprint. This study investigates a novel nitrogen-doped carbon nanomaterial as a promising metal-free electrocatalyst for CO₂ reduction. Graphenated carbon nanotubes (gCNTs) grown with a single step microwave plasma-enhanced chemical vapor deposition (MPECVD) process were doped with nitrogen via post-growth thermal annealing in ammonia. Scanning electron microscopy (SEM) was used to characterize the morphology of nitrogen-doped gCNTs (N-gCNTs) and x-ray photoelectron spectroscopy (XPS) characterization was used to quantify N-doping levels at various treatment temperatures from 650°C to 950°C. Graphitic and pyridinic forms of nitrogen present in these N-gCNTs were quantified by deconvolution of the XPS N 1s region.