Dimension Control of Platinum Nanostructures by Atomic Layer Deposition: From Surface Chemical Reactions to Applications

For over 20 years, atomic layer deposition (ALD) of platinum (Pt) has gained significant achievements in the fabrication of a variety of Pt nanostructures for applications in different fields, including microelectronics, sensors, catalysis, and energy conversion, storage, and utilization devices. By relying on its unique self-saturating surface reactions with diverse precursor chemistries, tunable deposition conditions, and various surface engineering methods, ALD offers the capability of controlling the amount of deposited Pt at the atomic level precision and enables the fabrication of various low-dimensional nanostructures, such as single atoms, nanoclusters, core/shell nanoparticles, and ultrathin continuous films. These ALD-fabricated Pt nanostructures not only provide outstanding performances but also maximize the Pt usage efficiency that can address the cost-related issues of Pt. Nevertheless, to achieve a controllable deposition, it is important to acquire a deep understanding on the precursor chemistry, the surface reaction, nucleation, and growth mechanisms, as well as the influence of deposition conditions and surface engineering, which are the key factors that govern the growth of Pt. By reviewing the advances in Pt ALD since its inauguration with the focus on these factors as well as its potential applications, we expect that this article can provide the fundamentals of Pt ALD, which may serve as a guide to achieve a desired Pt nanostructure for a targeted application.