A simple catalytic CVD method for the synthesis of N‐doped carbon nanocoils (CNCs), using acetonitrile as both the carbon and nitrogen source, is developed. A Ni–Fe layered double hydroxide that has not been subjected to any prior annealing or reducing treatment is used as a catalyst precursor. The steps of precursor‐to‐catalyst transformation, catalyst activation, deposition of CNCs, and nitrogen doping are performed in situ, in a single process.

Nitrogen-doped carbon nanocoils (CNCs) with adjusted morphologies were synthesized in a one-step catalytic chemical vapour deposition (CVD) process using acetonitrile as the carbon and nitrogen source. The nickel iron oxide/nickel oxide nanocomposites, which were derived from nickel-iron layered double hydroxide (LDH) precursors, were employed as catalysts for the synthesis of CNCs. In this method, precursor-to-catalyst transformation, catalyst activation, formation of CNCs, and nitrogen doping were all performed in situ in a single process. The morphology (coil diameter, coil pitch, and fibre diameter) and nitrogen content of the synthesized CNCs was individually adjusted by modulation of the catalyst composition and CVD reaction temperature, respectively. The adjustable ranges of the coil diameter, coil pitch, fibre diameter, and nitrogen content were confirmed to be approximately 500±100 nm, 600±100 nm, 100±20 nm, and 1.1±0.3 atom%, respectively.