2D Nanomaterial Supported Single‐Metal Atoms for Heterogeneous Photo/Electrocatalysis

Abstract

Single‐atom catalysts (SACs) attract intensive attention owing to their unmatched catalytic activities and high atom utilization. Besides metal species themselves, the substrates play a key role for the improvement of their catalytic performance by optimizing metal–support interactions and coordination structures. In the past years, various 2D nanomaterials have been employed to anchor single metal atoms for renewable energy technologies and other important industrial processes. Tremendous progress has been achieved in the development of 2D supported SACs for advanced energy conversion reactions. This article provides a comprehensive and critical review of up‐to‐date advances in the field of 2D supported SACs. The state‐of‐the‐art characterizations including ex/in situ microscopic and spectroscopic techniques are summarized with the emphasis on their specific superiorities in identifying the reactive sites and reaction mechanisms, combined with theoretical calculations and experimental results. A brief overview of various reactions including hydrogen evolution reaction (HER), oxygen evolution reaction (OER), two‐electron oxygen reduction reaction (2e‐ORR), carbon dioxide reduction (CO2RR), and nitrogen reduction reaction (NRR) under the framework of electrocatalysis and photocatalysis, is presented on basis of versatile 2D nanomaterial supports. Last, the key challenges and opportunities in this rising field are highlighted.

Heterostructured Bimetallic MOF‐on‐MOF Architectures for Efficient Oxygen Evolution Reaction

“…The results reveal that the E d of Ni 3d in MOF‐(74 + 274)@NFF is −1.133 eV, in closer proximity to Fermi level compared to MOF‐274@NFF (−1.557 eV) and MOF‐74@NFF (−2.011 eV), corresponding to the stronger binding energy for oxygen intermediates. [ 31 ]…”

High-entropy alloys in electrocatalysis: from fundamentals to applications

“…16a). [277][278][279] To achieve the reduction of O 2 to water, it is necessary to have highly active electrocatalysts that can overcome the slow kinetics and high overpotential. 280,281 In the 4e pathway, this process can take place through either a direct or indirect mechanism.…”

Urea with trifunctional effects: an assistant for high exposure of single-atom active sites on 2D nanosheets via structural transformation

“…[13][14][15] Compared to the widely reported there-dimensional (3D) carbon substrates such as MOF-derivatives that possess abundant active sites buried inside their 3D structure, 2D mesoporous carbon materials with high specic surface area and multi-scale channels provide adequate exposure of active sites and rapid mass/electron transfer, and they have been constructed as ideal supports for loading atomic Fe. [16][17][18] It is a common strategy to direct the morphology of a catalyst by introducing inducers. 19,20 Particularly, the salt-induced thermal exfoliation strategy provides an efficient way for the construction of 2D mesoporous carbon materials since it can inherit the elements of the precursor and transform it into a hierarchical porous layered structure.…”