The Role of Supported Atomically Distributed Metal Species in Electrochemistry and How to Create Them

Abstract

Supported atomically distributed metal species are extensively applied as catalysts to exceed the properties of their bulk analogues. Their electronic structures can be easily tuned by neighboring support atoms or ligands to control their activities for different reactions. The high accessibility and therefore almost 100 % reactivity of the highly distributed active sites provide new opportunities for electrochemical applications that were previously only suitable for noble metals. Although a lot of work has been done in this area, the demand for large‐scale applications and, therefore, also large‐scale production is still far from sufficient. In this Review, we selected some recent publications to show the current state of applications of dispersed single‐atom catalysts in the oxygen reduction/evolution reaction and hydrogen evolution reaction, with a focus on their mechanisms in reactions, the underlying challenges, and synthesis methods. A further discussion on how the electrocatalytic performance of the supported single atom catalysts can be tailored to meet the requirements of large‐scale applications is also proposed.

Rational Design of Single‐Atom Site Electrocatalysts: From Theoretical Understandings to Practical Applications

“…[184][185][186] The HER is a two electron-transfer reaction, while OER is four electron-transfer reaction, thus, OER requires a relative high potential to overcome the reaction barriers. [186,187] Today, the widely used commercial OER catalyst is RuO 2 and IrO 2 . Large-scale applications also require a promising alternative with high performance, low cost, and abundant reserves.…”

Electronic Structure of Atomically Dispersed Supported Iridium Catalyst Controls Iridium Aggregation

“…Atomically dispersed supported metals are drawing widespread attention, because they offer catalytic properties different from those of conventional supported metals (which incorporate metal nanoparticles or clusters), and they have the advantage of maximum utilization of the often-expensive metals. − The catalytic properties of atomically dispersed metals are dependent on their ligands, and these include the supports. − …”

Material Science for catalysis: Quo vadis?

“…Without doubt the former calls is suitable for fundamental studies that imply the need to know where the atoms are in space. The latter allow for the embodiment of modern trends like "single atom catalysis" [10,11] or "high entropy catalysis" [12] where isolated species or statistical mixtures are the target of synthesis. The debate as to which of the two prototypes are more valuable goes back to the dispute about the nature of active sites that are either regular as on crystalline surfaces [13] ("Langmuir-type") or isolated "aristocratic" [14] local configurations on a non-translational surface ("Taylor-type").…”