Coordination tailoring of Cu single sites on C3N4 realizes selective CO2 hydrogenation at low temperature

Abstract

CO2 hydrogenation has attracted great attention, yet the quest for highly-efficient catalysts is driven by the current disadvantages of poor activity, low selectivity, and ambiguous structure-performance relationship. We demonstrate here that C3N4-supported Cu single atom catalysts with tailored coordination structures, namely, Cu–N4 and Cu–N3, can serve as highly selective and active catalysts for CO2 hydrogenation at low temperature. The modulation of the coordination structure of Cu single atom is readily realized by simply altering the treatment parameters. Further investigations reveal that Cu–N4 favors CO2 hydrogenation to form CH3OH via the formate pathway, while Cu–N3 tends to catalyze CO2 hydrogenation to produce CO via the reverse water-gas-shift (RWGS) pathway. Significantly, the CH3OH productivity and selectivity reach 4.2 mmol g–1 h–1 and 95.5%, respectively, for Cu–N4 single atom catalyst. We anticipate this work will promote the fundamental researches on the structure-performance relationship of catalysts.

Single Atom Catalysts for Selective Methane Oxidation to Oxygenates

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Photocatalytic CO2reduction on Cu single atoms incorporated in ordered macroporous TiO2toward tunable products

“…[8][9][10][11][12] Among them, copper (Cu) has been identified as one of the most promising cocatalysts to convert CO 2 into various hydrocarbons owing to its optimum binding ability with CO 2 and reaction intermediates. [13][14][15][16] The individual Cu atoms immobilized on light-harvesting semiconductors can act as excellent active sites for activating CO 2 molecules and stabilizing reaction intermediates in the photocatalytic CO 2 reduction reaction. 17,18 Moreover, the introduction of highly dispersed Cu heteroatoms in light-harvesting semiconductors can broaden the light-adsorption range and enhance the photoexcited charge separation efficiency.…”

Research progress of asymmetrically coordinated single-atom catalysts for electrocatalytic reactions

“…1 Single atom catalysts (SACs) have the advantages of unique electronic and geometric structures, nearly 100% atomic utilization, ideal catalytic activity, and excellent product selectivity and stability. 2–5 Therefore, it has been rapidly developed in many fields such as electrocatalysis, 6 photocatalysis, 7 and enzyme catalysis. 8 At present, researchers are focusing on regulating various conditions of SACs to enhance their intrinsic activity and persistence, such as carriers, heteroatoms, coordination numbers, etc.…”