Living Atomically Dispersed Cu Ultrathin TiO₂ Nanosheet CO₂ Reduction Photocatalyst

Abstract

Supported atomically dispersed metals are proving to be efficacious photocatalysts for CO 2 reduction to solar fuels. While being atom efficient, they suffer from being noble, rare, and costly (Pt, Pd, Au, Ag, Rh) and lacking in long‐term stability. Herein, all of these problems are solved with the discovery that atomically dispersed Cu supported on ultrathin TiO 2 nanosheets can photocatalytically reduce an aqueous solution of CO 2 to CO. The atomically dispersed Cu can be recycled in a straightforward procedure when they become oxidatively deactivated. This advance bodes well for the development of a solar fuels technology founded on abundant, low‐cost, nontoxic, atomically dispersed metal photocatalysts.

Atomic‐Level Reactive Sites for Semiconductor‐Based Photocatalytic CO2 Reduction

“…This is because Cu (0) with a low Fermi level is prone to accumulate electrons and Cu (I) is an active site to promote formation of CH 4 . Interestingly, atomically dispersed Cu on the ultrathin nanosheets is processed by photodeposition methods and Cu 0 is oxidized to Cu + with reducing CO 2 to CO.…”

Tungsten bronze Cs0.33WO3 nanorods modified by molybdenum for improved photocatalytic CO2 reduction directly from air

“…Recently, the photocatalyst WO 3 has attracted increasing attention from researchers studying CO 2 reduction. Given its relatively narrow bandgap (2.4-2.8 eV), stable chemical properties, CO 2 adsorption ability, and relatively low conduction band position, WO 3 prevents the buildup of H 2 during the CO 2 reduction reaction [13][14][15][16][17]. However, the photocatalytic CO 2 reduction activity of WO 3 is still low, due to the poor reductive capacity of the conduction band, the high-charge recombination and the limited number of active sites available for CO 2 activation [18,19].…”

Atomic Thickness Catalysts: Synthesis and Applications

“…Wet-chemical synthesis Noble-metals (alloys), Rh, [53] Pd, [24] Rh@Pt nL , [120] Pd-Pt-Ag, [22] PdMo, [18] PtPdNi, [59] RuCu, [56] AL-Pt@Pt 3 Ga, [21] PtGa [25] ORR, [18,25,59] OER, [9] CRR, [24] MOR, [21,53] EOR [22,120] HER [92] Metallic TMDs, 1T′-MoS 2 [92] LDHs, NiFe-LDHs [9] Hydro/solvothermal synthesis Metal (alloys) Rh, [46] RhPd-H, [3] NiCo, [64] NiMo [65] HER, [3,48,51,65] OER, [8,51] CRR [11] TMOs, MnO 2 , [51] TiO 2 , [48] Ni(OH) 2 [8] Other ATCs: Bi 3 O 4 Br [11] Template-assisted synthesis Various kinds of ATCs, Bi, [91] Fe, [69] Au, [70] PdCo, [80] Sn confined in graphene, [31] 1T-MoS 2 /NiS 2 , [20] hexagonal-MoO 3 [73] ORR, [80] CRR, [91] HER [20] Electrochemistry-assisted synthesis Monolayer metal layer: Pt AL @...…”

“…In addition, extensive researches on nonlayered nanostructured ATCs further enriched the exploration of ATCs family members. To name a few, nonlayered based metallene, [18,22,46,47] and transition metal oxides [48][49][50][51] have been recently developed with atomic thickness. As a typical example, promising catalytic performance can be emerged after rationally reducing down the thickness of nonlayered Co in bulk.…”

“…Hence, photogenerated charge carriers could migrate fast from inside of the materials to the surface which were induced by these quantum effects [11,50] In particular, the exposed surface atoms with sufficient dangling bonds could establish the interaction with CO 2 molecules and facilitate the formation of surface defects to enhance the CO 2 activity and selectivity. [137] Benefiting from these merits, atomically thin photocatalysts including WO 3 layers, [138,139] Cu doped TiO 2 NSs, [48] ultrathin ZnAl LDH, [140] single-unit-cell BiVO 4 , [6] one-unit-cell ZnIn 2 S 4 , [141] ZnGa 2 O 4 NSs, [142] Bi 2 WO 6 layers, [143] Bi 2 MoO 6 NSs, [144] and Co doped Bi 3 O 4 Br [11] have been developed for photocatalytic CRR.…”