Phosphorus Tailors thed‐Band Center of Copper Atomic Sites for Efficient CO₂Photoreduction under Visible‐Light Irradiation

Abstract

Photoreduction of CO 2 into solar fuels has received great interest, but suffers from low catalytic efficiency and poor selectivity. Herein, two single-Cuatom catalysts with unique Cu configurations in phosphorus-doped carbon nitride (PCN), namely, Cu 1 N 3 @PCN and Cu 1 P 3 @PCN were fabricated via selective phosphidation, and tested in visible light-driven CO 2 reduction by H 2 O without sacrificial agents. Cu 1 N 3 @PCN was exclusively active for CO production with a rate of 49.8 μmol CO g cat À 1 h À 1 , outperforming most polymeric carbon nitride (C 3 N 4 ) based catalysts, while Cu 1 P 3 @PCN preferably yielded H 2 . Experimental and theoretical analysis suggested that doping P in C 3 N 4 by replacing a corner C atom upshifted the d-band center

Potassium and Sulfur Dual Sites on Highly Crystalline Carbon Nitride for Photocatalytic Biorefinery and CO2 Reduction

“…Besides, the calculated free energy for the photoreduction of CO 2 to CO by K/S@CN-0.5 is depicted in Figure S18. In general, this process involved the first e – and proton transfer to produce the *COOH intermediate, followed by the second proton-coupled e – to form the *CO intermediate and H 2 O, and the desorption of the absorbed *CO to produce the final CO product. ,, …”

“…In general, this process involved the first e − and proton transfer to produce the *COOH intermediate, followed by the second proton-coupled e − to form the *CO intermediate and H 2 O, and the desorption of the absorbed *CO to produce the final CO product. 13,59,60 The above experimental analysis and the previous studies 10,30,60−65 were combined to propose a possible mechanism for photocatalytic CO 2 reduction and oxidation of xylose via K/S@CN-0.5. As depicted in Figure S19, K/S@ CN-0.5 possessed excellent light capture capabilities and produced photoexcited e − −h + under visible light irradiation.…”

“…The *COOH intermediate subsequently forms CO by accepting protons and e − as well as by dehydration. 60 For the photocatalytic oxidation of xylose, the presence of various oxidation-active species and their role in xylose oxidation were demonstrated by ESR characterization and poisoning tests. The process of xylose to lactic acid under the alkali condition during the photocatalytic reaction first involves the isomerization of xylose to xylulose.…”

Designing a Built-In Electric Field for Efficient Energy Electrocatalysis

“…Electrocatalytic CO 2 RR could convert CO 2 into value-added chemicals or fuels, − which involves 2, 4, 6, 8, 12, or even more electron-transfer processes . Taking formate as an example, its production needs two electrons to take part in , CO 2 + * ⇌ *CO 2 (1); *CO 2 + e – → *CO 2 •– (2); *CO 2 •– + HCO 3 – → *OCHO • + CO 3 2– (3); *OCHO • + e – → *OCHO – (4); *OCHO – → HCOO – + * (5). The key step of formic formation is eq , where the oxygen atom of *CO 2 •– binds to the electrode surface, and the carbon atom is protonated to form *OCHO .…”

“…Electrocatalytic CO 2 RR could convert CO 2 into value-added chemicals or fuels, 139−141 which involves 2, 4, 6, 8, 12, or even more electron-transfer processes. 142 Taking formate as an example, its production needs two electrons to take part in 143,144 5). The key step of formic formation is eq 3, where the oxygen atom of *CO 2…”