Constructing N-Coordinated Co and Cu Single-Atomic-Pair Sites toward Boosted CO₂ Photoreduction

Abstract

The visible-light-driven photocatalytic reduction reaction of carbon dioxide (CO 2 ) (CO 2 RR) to value-added fuels presents a feasible approach to curb anthropogenic CO 2 emissions and mitigate the increasing energy crisis. However, developing photocatalysts with excellent performance still remains a great challenge in this field. Herein Co,Cu,N-codoped carbon nanoparticles (Co 1 Cu 1 /NC) were fabricated through the pyrolysis of zeolitic imidazolate framework (ZIF-8) with Cu(NO 3 ) 2 adsorbed inside the cavities and CoTBPP decorated over the surface of ZIF. Spherical aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and electron energy loss spectroscopy measurements disclose the dual-metal single-atomic nature of Co 1 Cu 1 /NC consisting of atomically dispersed Co−Cu pair sites on a nitrogen-doped carbon support. Extended X-ray absorption fine-structure analysis reveals the tetra-N-coordinated nature of each metal in Co 1 Cu 1 /NC (N 2 −Co−N 2 −Cu−N 2 ). For the purpose of comparative study, Co,N-and Cu,N-codoped carbon nanoparticles (Co 1 /NC and Cu 1 /NC) also with single atomic site nature have been fabricated following the same route. The as-prepared Co 1 Cu 1 /NC exhibits highly effective photocatalytic CO 2 -to-CO reduction with a considerably high CO-generating yield of 22.46 mmol g −1 and a CO selectivity of 83.4% after 2 h of visible-light irradiation. Experimental characterizations and in particular theoretical calculations disclose the close association of the remarkable CO 2 RR catalytic activity of Co 1 Cu 1 /NC with the synergetic effect of the Co−Cu atomic-pair sites, which facilitate the conversion of CO 2 to CO via lowering the energy barrier for the formation of the *COOH intermediate. This work paves a new avenue for the rational design and construction of atomic-pair photocatalysts with boosted performance.

Mixed-Blocks-Driving Nickel–Porphyrin Covalent Organic Polymers for Photocatalytic Syngas Production from CO2 with Fine Selectivity

“…Meanwhile, the reduced species can transfer an electron to the surface of O X S Y –Ni COPs. Subsequently, the Ni 2+ –porphyrin core accepted electrons to reduce the CO 2 molecules as well as active protons provided by TEOA . Additionally, more electrons in the Ni 2+ -free porphyrin core tended to reduce active protons.…”

“…Subsequently, the Ni 2+ −porphyrin core accepted electrons to reduce the CO 2 molecules as well as active protons provided by TEOA. 53 Additionally, more electrons in the Ni 2+ -free porphyrin core tended to reduce active protons. More importantly, the amount of furan and thiophene regulates the reduction capacity and charge kinetics of the semiconductor so that the syngas ratio can be controlled.…”

Robust Zn(II)-Organic Framework for High Catalytic Activity on Cycloaddition of CO2 with Epoxides and Reversible Iodine Uptake

“…As for the topology of NUC-69 , the host framework can be viewed as a 4,4 binding three-dimensional network with the Schläfli symbol of {3·4·5} by simplifying both H 2 DDBB 2– and Zn 2+ as 4-connected nodes, as shown in Figure b.…”

“…In addition, with the process of industrial modernization, the concentration of carbon dioxide (CO 2 ) in the atmosphere is gradually increasing, leading to environmental safety that cannot be ignored, for instance, global warming, acidification of the oceans, global extreme climate, land inundation, and mass species die-offs. − According to the prediction from Intergovernmental Panel on Climate Change (IPCC), atmospheric CO 2 enrichment has been increasing from 280 ppm in the early 19th century to 400 ppm in the early 21st century, which will be up to 950 ppm without human intervention at the end of this century. − Therefore, for the survival and development of mankind, it is necessary and impendency to decrease the emission and mitigate the concentration of atmospheric CO 2 . At present, carbon capture and storage technologies are widely adopted to decrease factitious CO 2 emissions, which also bring new problems, for example, energy consumption during the process of separation–purification–compression–transportation as well as storage. − To meet the demands of the age, a cascade strategy composed of capture and conversion of CO 2 has brought about widespread attention because the generated products can be effectively employed as industrial raw materials, incidentally solving the energy crisis.…”

Photocatalytic Reduction of Carbon Dioxide to Methanol: Carbonaceous Materials, Kinetics, Industrial Feasibility, and Future Directions

“…In the last three decades, numerous research efforts have been made to develop active heterogeneous catalysts for the conversion of CO 2 by three processes to produce methanol. A large number of review articles, publications, and books ,,,− have been published on research topics of CO 2 conversion such as CO 2 utilization by thermal catalysis, , electrocatalytic reduction, , photocatalytic synthesis, ,,− plasma, and other methods. − Recently, the research group of Shanmuga and Ramyashree published a review article on MOF compounds for PCCR of methanol . In 2022, Gawande’s group discussed recent developments in the photocatalytic hydrogenation of CO 2 to methanol.…”