Insights into Single‐Atom Metal–Support Interactions in Electrocatalytic Water Splitting

Abstract

Electrochemical water splitting is a promising approach for energy conversion and storage. The exploration of low‐cost, efficient, and durable electrocatalysts is of great significance for realizing a large‐scale application and forming a sustainable chemistry. Recently single‐atom catalysts (SACs), with isolated metal atoms anchored on supports, exhibit distinctive performances for electrocatalytic water splitting. Single‐atom catalysis is emerging as a new frontier for bridging the homogeneous and heterogeneous catalyses. Therefore, the synthesis of SACs with excellent durability is highly desirable but challenging. Here, recent progress of SACs in supports and synthetic strategies, characterization techniques, and the electrochemical application toward water splitting is summarized. Fully understanding the interactions between the single‐atom metal and the support is extremely important for the design and preparation of highly stable SACs as well as the improvement of electrocatalytic activity, which are particularly discussed in this context. Finally, the current challenges and future opportunities for the development of this field are discussed.

Designing Atomic Active Centers for Hydrogen Evolution Electrocatalysts

“…[69,70] During HER catalysis,t he coordination environment affects the chargetransfer process,w hich leads to av ariation in the adsorption and desorption of hydrogen (measured as DG H* )a sw ell as modulation of the HER performance. [71] In detail, when single metal atoms are coordinated to the supports,electron transfer The evolution of hydrogen from water using renewable electrical energy is at opic of current interest. Pt/C exhibits the highest catalytic activity for the H 2 evolution reaction (HER), but scarce supplies and high cost limit its large-scale application.…”

Densely Populated Single Atom Catalysts

“…Electrochemical energy storage and conversion technology have been widely studied to produce sustainable and renewable energy . Many advanced clean energy technologies, such as fuel cells, metal air batteries, and water splitting, etc., require highly active catalysts to lower the energy barrier and increase the reaction rate with an efficient and stable route.…”

Recent Advances in Atomic‐Level Engineering of Nanostructured Catalysts for Electrochemical CO2 Reduction

“…HAADF‐STEM has become an essential tool to visualize the isolated metal sites and their local environment in single‐atom catalysts. [ 37 ] When the contrast of the isolated metal atoms is obviously different from that of the atoms in the support, the atom doping site and density can be directly visualized. As shown in Figure a,b, due to the higher atomic number of Ni atom compared with C and N atoms, isolated Ni sites were clearly observed as much brighter dots in the N‐doped carbon nanotubes.…”

“…Since the pioneering work on confirming the existence of stable supported single‐atom catalyst (SAC) by Zhang's group, [ 84 ] SACs have been extensively studied in the systems of energy storage and conversion. [ 37,85 ] Compared with metal nanoparticles, SACs are able to maximize the metal utilization, simplify the catalytic model, and boost the catalytic activity. The catalytic properties of SACs are highly sensitive to their structures and mass loading.…”