Nitrogen-doped carbon nanotubes coated by atomic layer deposited SnO2 with controlled morphology and phase

Atomic layer deposition (ALD) was used to synthesize metal oxide-carbon nanotube (MO-CNT) hybrid materials by coating nitrogen-doped CNTs (N-CNTs). SnO2-CNT hybrids were produced using SnCl4 and water as precursors and exhibited many unique features. It was demonstrated that the use of N-CNTs was beneficial for directly initiating the ALD of SnO2 (ALD-SnO2) and that adjustable ALD parameters were favorable for controlling the morphology and phase of the deposited SnO2. The cyclic and surface-controlled nature of ALD contributed to the morphologies of SnO2 tunable from nanoparticles to nanofilms, and the temperature-dependent characteristics of the ALD-SnO2 rendered the phases of SnO2 controllable with amorphous, crystalline, or a mixed phase by the former two. Furthermore, this study also explored the underlying mechanisms for the controlled synthesis of SnO2-CNT hybrid materials.