Multifunctional Au/Hydroxide Interface toward Enhanced C–C Coupling for Solar-Driven CO₂ Reduction into C₂H₆

Abstract

The high-grade C2+ products from CO2 photoreduction are limited by the kinetic bottleneck. Herein, a multifunctional Au/hydroxide interface was put forward to improve the C–C coupling. As a prototype, the synthesized Au/ZnSn(OH)6 tuned the CO generation and afforded about 50% electrons toward C2H6 selectivity. The prominent enhancement resulted from the following effects: (1) strong metal–support electronic interactions built an electric field at the interface of ZnSn(OH)6 nearby the Au nanoparticles, leading to fast transfer of electrons for the C–H and C–C bonding reactions. (2) The surface solid-state Sn–OH and Zn–OH lattice hydroxyls served as donors to feed rich H+ and oxygen vacancies (OVs) via hole-induced oxidation for the boosted C2H6 formation. (3) The synergetic OVs and Au sites allowed efficient e–/H+ to boost *CO hydrogenation toward *CH3 and *CH3*CH3 formation into the C2H6 product.

Strong Electronic Interaction Enables Enhanced Solar-Driven CO2 Reduction into Selective CH4 on SrTiO3 with Photodeposited Pt2+ Sites

“…These results suggested that the tuned selectivity from CO to CH 4 was independent of the carrier density on the SrTiO 3 surface, although it indeed presented a positive role for the CH 4 yield. Indeed, similar results were previously demonstrated on Ta 3 N 5 and ZnSn­(OH) 6 . , Insight into the reaction reveals that the difference was that the CO 2 reduction occurred on the {100} facet and Pt 2+ -based cocatalyst for SrTiO 3 and x Pt 2+ -SrTiO 3 , respectively, as confirmed by the TEM and VB-XPS result. Hence, this confirmed that the different CO and CH 4 selectivity for the CO 2 reduction was dependent on the different surface chemistry with the present Pt 2+ species.…”

“…Indeed, similar results were previously demonstrated on Ta 3 N 5 and ZnSn(OH) 6 . 29,30 Insight into the reaction reveals that the difference was that the CO 2 reduction occurred on the {100} facet and Pt 2+ -based cocatalyst for SrTiO 3 and xPt 2+ -SrTiO 3 , respectively, as confirmed by the TEM and VB-XPS result.…”

Stable CO2 reduction under natural air on Ni–Sn hydroxide photocatalyst with dynamic renewable oxygen vacancies

“…These results suggested that the NiSn(OH) 6 was promising for the CO 2 RR in natural air, despite the low CO 2 and H 2 O concentration. , E RHE = −1.9 V) was quilt difficult in thermodynamics [14]. The above results convinced the advantage of the NiSn(OH) 6 that is flexible and widely applicable for the CO 2 RR.…”

“…The surface metastable oxygen vacancies (V O ) are active sites playing strong interaction with the CO 2 or H 2 O molecule, thus accelerating the reaction rate by lowering the activation barriers [13,14]. As revealed, the V O could easily capture the CO 2 or H 2 O molecule by anchoring their oxygen atoms at the vacancy sites, and the V O -induced metal ions with unsaturated coordination (M δ+ ) could serve as the electron donor, thus weakening the corresponding oxygenbased bonding energy as a result of the molecule polarization [15][16][17][18].…”