Ultralow Loading (Single‐Atom and Clusters) of the Pt Catalyst by Atomic Layer Deposition Using Dimethyl ((3, 4‐η) N, N‐dimethyl‐3‐butene‐1‐amine‐N) Platinum (DDAP) on the High‐Surface‐Area Substrate for Hydrogen Evolution Reaction. Issue 3 (15th December 2020) - Ramesh, Rahul
Abstract: Single‐atom Pt catalyst has seen a tremendous surge in the research community in very recent times. The minimum loading of such precious metal catalysts on high surface area substrates with effective performance toward catalyzing a reaction is indeed of great importance. Here, an alternative way is demonstrated to perform an ultralow loading of Pt catalyst by atomic layer deposition (ALD) using dimethyl ((3, 4‐η) N, N ‐dimethyl‐3‐butene‐1‐amine‐ N ) platinum precursor (C8 H19 NPt). The ultralow loading of Pt catalyst is performed on highly porous nitrogen–carbon‐powder coated carbon cloth (NC–CC) substrates by varying the number of ALD cycles (2 to 60), and their performance in electrochemical hydrogen evolution reaction (HER) is evaluated. The inductively coupled plasma‐optical emission spectrometry provides the exact mass of the Pt catalyst, whereas, the transmission electron microscopy images confirm the uniform and homogeneous dispersion of platinum single‐atoms and clusters (with an average size of <1 nm for ten ALD cycles) on the NC–CC substrate. It is further found that the mass activity of Pt catalyst (per microgram of Pt) toward HER is extraordinarily high for less number of ALD cycles (two and five), whereas, the overall performance (current density per geometrical area) becomes more and more improved with increasing the ALD cycles. Abstract : Atomic layer deposition (ALD) of Pt using dimethyl [(3, 4‐η) N, N ‐dimethyl‐3‐butene‐1‐amine‐ N ] platinum and oxygen forms single‐atom/cluster [Pt(OH)2 ] on porous nitrogen‐carbon (NC)‐powder coated carbon cloth. Hydrogen evolution reaction activity as a function of ALD cycles recommends an optimum loading of ALD‐Pt using 10–30 cycles for a more realistic approach toward its practical implementation.