Self‐Polarization Triggered Multiple Polar Units Toward Electrochemical Reduction of CO₂ to Ethanol with High Selectivity

Abstract

Electrochemical conversion of CO 2 to highly valuable ethanol has been considered a intriguring strategy for carbon neutruality. However, the slow kinetics of coupling carbon-carbon (CÀ C) bonds, especially the low selectivity ethanol than ethylene in neutral conditions, is a significant challenge. Herein, the asymmetrical refinement structure with enhanced charge polarization is built in the vertically oriented bimetallic organic frameworks (NiCu-MOF) nanorod array with encapsulated Cu 2 O (Cu 2 O@MOF/CF), which can induce an intensive internal electric field to increase the CÀ C coupling for producing ethanol in neutral electrolyte. Particularly, when directly employed Cu 2 O@MOF/CF as the self-supporting electrode, the ethanol faradaic efficiency (FE ethanol ) could reach maximum 44.3 % with an energy efficiency of 27 % at a low working-potential of À 0.615 V versus the reversible hydrogen electrode (vs. RHE) using CO 2 -saturated 0.5 M KHCO 3 as the electrolyte. Experimental and theoretical studies suggest that the polarization of atomically localized electric fields derived from the asymmetric electron distribution can tune the moderate adsorption of *CO to assist the CÀ C coupling and reduce the formation energy of H 2 CCHO*-to-*OCHCH 3 for the generation of ethanol. Our research offers a reference for the design of highly active and selective electrocatalysts for reducing CO 2 to multicarbon chemicals.

Correction and new understanding of the reactivity of illuminated tungsten trioxide in the dark: antecedents and consequences of photo-storage electrons triggering Fenton reactions

“…The peaks at 530.49 eV and 532.34 eV in the O 1s spectrum of the unilluminated h-WO 3 ·0.46H 2 O are assigned to the lattice O in hexagonal WO 3 and the adsorbed water molecules on the surface of the sample (Fig. 3b), 24–27 respectively. As for the W 4f spectrum of the unilluminated h-WO 3 ·0.46H 2 O, the two peaks at 35.79 eV and 37.93 eV are attributed to the spin–orbit splitting of the W 4f components (W 4f 7/2 and W 4f 5/2 ) (Fig.…”

Spatially and Temporally Resolved Dynamic Response of Co-Based Composite Interface during the Oxygen Evolution Reaction

“…The high asymmetric electron distribution of the Co active site in Co–B@Co 3 O 4 /Co 3 O 4 NSs induces a large spin polarization, which causes partial orbital occupation and provides enough exchange stabilization energy to generate the d−π* interactions, thus forcing *O/*OOH to be of a radical nature, which can be further activated (Figures S81, S82, S85, S86 and Table S17). Meanwhile, there is a large contribution of antibonding orbitals, as shown by the corresponding ICOHP (Table S16). Therefore, although the adsorption is relatively weak, there is a strong interaction between O and Co sites to trigger different main adsorption configurations, which trigger the formation of highly activated *O/*OOH radicals. , Furthermore, from Bader charge analysis, the Bader charge of adsorbed *O on Co–B@Co 3 O 4 /Co 3 O 4 NSs-CoI increases from −1.11 to −0.54e – after the deprotonation and the adsorbed *OOH has a charge of −0.31e – , which is more close to zero and exhibits a more obvious oxygen radical feature than Co 3 O 4 NSs (Table S17).…”

Modulating the localized electronic distribution of Cu species during reconstruction for enhanced electrochemical CO2 reduction to C2+ products

“…1–10 The conversion of CO 2 into valuable chemical fuels through electrochemistry can benefit from being powered by green electricity and is easy to modularize and scale up, and is regarded as one of the most promising technologies for carbon neutrality. 11–14 Catalysts as the core of the CO 2 RR have been extensively studied, and multiple catalysts have been designed to achieve different products, such as CO, 15 formate, 16 ethanol, 17 and ethylene. 18 Among them, C 1 products such as CO and formate have commonly achieved a high selectivity of over 90%.…”