Dual‐Single‐Atom Tailoring with Bifunctional Integration for High‐Performance CO₂ Photoreduction

Abstract

Single‐atom photocatalysis has been demonstrated as a novel strategy to promote heterogeneous reactions. There is a diversity of monoatomic metal species with specific functions; however, integrating representative merits into dual‐single‐atoms and regulating cooperative photocatalysis remain a pressing challenge. For dual‐single‐atom catalysts, enhanced photocatalytic activity would be realized through integrating bifunctional properties and tuning the synergistic effect. Herein, dual‐single‐atoms supported on conjugated porous carbon nitride polymer are developed for effective photocatalytic CO2 reduction, featuring the function of cobalt (Co) and ruthenium (Ru). A series of in situ characterizations and theoretical calculations are conducted for quantitative analysis of structure–performance correlation. It is concluded that the active Co sites facilitate dynamic charge transfer, while the Ru sites promote selective CO2 surface‐bound interaction during CO2 photoreduction. The combination of atom‐specific traits and the synergy between Co and Ru lead to the high photocatalytic CO2 conversion with corresponding apparent quantum efficiency (AQE) of 2.8% at 385 nm, along with a high turnover number (TON) of more than 200 without addition of any sacrificial agent. This work presents an example of identifying the roles of different single‐atom metals and regulating the synergy, where the two metals with unique properties collaborate to further boost the photocatalytic performance.

Emerging Ultrahigh‐Density Single‐Atom Catalysts for Versatile Heterogeneous Catalysis Applications: Redefinition, Recent Progress, and Challenges

“…[149] In recent years, SACs have large metal utilization rate and highly density active sites and show excellent performance in many important catalytic reactions, which also provide a favorable research basis for exploring new AFC materials for photocatalytic CO 2 reduction reaction (see Table 3). [52,57,[150][151][152][153][154][155] Recently, Ma et al [150] proposed a pyrolysis-induced vaporization strategy to fabricate ultrahigh-density Co 1 /g-C 3 N 4 SACs with a record metal loading of 24.6 wt%, which revealed remarkable activity and selectivity for photocatalytic CO 2 reduction to CH 3 OH in the absence of both sacrificial reagent and photosensitizer (see Figure 15A-C). The Co single atoms were prepared by the pyrolysis-induced vaporization process in a two-step calcination procedure.…”

“…In addition to polymer carbon nitride semiconductors [57,[150][151][152][153][154][155] and MOF [52] supports, metal compound semiconductor-based supports have also been used to design SAC for photocatalytic CO 2 reduction. [160,161] For example, Zhou et al lately reported a novel concept of interfacial electron concentration regulation in Au 1 -modified CdS support (Au 1 /CdS), which for the first time realized electron enrichment at Cd cationic vacancy sites rather than Au atomic sites.…”

“…The geometric coordination environment and electronic structure of central metal atoms in SACs (especially for AFCs) are very important to the catalytic characteristics for heterogeneous catalysis (based on the intrinsic structure-performance relationship [30,155,228,246,247] and metal-support interaction [37,111,218] ). For heterogeneous catalysis (thermal-/photo-/electrocatalysis), the SACs provide a simplified model for the study of the catalytic reaction mechanism due to the simple structure of the active center (with the same single-site structure [6,96] ).…”

Synergy between Palladium Single Atoms and Nanoparticles via Hydrogen Spillover for Enhancing CO2 Photoreduction to CH4

“…In addition, photocatalytic CO 2 methanation is also able to mitigate the increasing CO 2 concentration in the atmosphere. Nevertheless, complex CO 2 photoreduction processes often lead to a wide range of possible products, [10][11][12][13][14] and the effective photoreduction of CO 2 into CH 4 remains a huge challenge.…”

A 0D/2D Bi₄V₂O₁₁/g-C₃N₄ S-scheme Heterojunction with Rapid Interfacial Charges Migration for Photocatalytic Antibiotic Degradation

“…With the rapid development of industry, large numbers of organic pollutants are misused in the various fields of life, which brings serious environmental problems [1][2][3][4] . It is well known that semiconductor photocatalytic technology is an eco-friendly and valid way to degrade and remove the typical contaminants, and photocatalyst plays a key role in the application of this technology [5][6][7][8] . Thus, the various semiconductor materials have been used in the field of pollutants removal.…”