Pt Atom on the Wall of Atomic Layer Deposition (ALD)-Made MoS 2 Nanotubes for Efficient Hydrogen Evolution.

Single-atom catalysts (SACs) can achieve excellent catalytic efficiency at ultralow catalyst consumptions. Herein, platinum (Pt) atoms are fixed on the wall of atomic layer deposition (ALD)-made molybdenum disulfide nanotube arrays (MoS 2 -NTA) for efficient hydrogen evolution reaction (HER). More concretely, MoS 2 -NTA with different nanotube diameters and wall thicknesses are fabricated by a sacrificial strategy of anodic aluminum oxide (AAO) template via ALD; then Pt atoms are fixed on the wall of Ti 3 C 2 -supported MoS 2 -NTA as a catalytic system. The MoS 2 -NTA/Ti 3 C 2 decorated with 0.13 wt.% of Pt results in a low overpotential of 32 mV to deliver a current density of 10 mA cm -2 , which is superior to 20 wt.% commercial Pt/C (41 mV). Ordered MoS 2 -NTA instead of 2D MoS 2 prevents Pt atoms from aggregating and then exerts catalytic activities. The density functional theory calculations suggest that the Pt atoms are more likely to occupy the sites on the tubular MoS 2 than the planar MoS 2 , and the Pt atoms accumulated at the Mo site of MoS 2 -NT have a moderate Gibbs free energy (close to zero).