Regulating *OCHO Intermediate as Rate‐Determining Step of Defective Oxynitride Nanosheets Enabling Robust CO₂ Electroreduction

Abstract

hydrogen storage and formate fuel cells. [5] Notably, a tremendous amount of reports are devoted to exploring the advanced electrocatalysts for formate production through the electrochemical CO 2 reduction reaction (CO 2 RR). Among these catalysts, In-based materials, including oxides, [6][7][8] nitrides, [9] sulfides, [10,11] MOFs, [12][13][14][15] pure metal, [16,17] and singleatom catalysts, [18,19] have attracted extensive attentions owing to their features of high formate selectivity and low toxicity. However, these catalysts still suffer the problems of large thermodynamic energy barrier and sluggish kinetic activity. Therefore, it is essential to develop a kind of efficient In-based catalysts for enhancing the catalytic activity of CO 2 RR.As is well known, the adsorption and hydrogenation processes are of great importance for converting the CO 2 to value-added chemicals. [20] All kinds of strategies have been explored to optimize the adsorption and hydrogenation processes of CO 2 RR, such as heterojunction engineering, [21][22][23] defect engineering, [24][25][26] doping engineering [27,28] etc. For instance, the adsorption capacity of CO 2 increases obviously by coupling the SnS nanosheets with the N-species, thus achieving a high formate selectivity of 92.6% with a significant formate partial current density of 41.1 mA cm -2 at a low overpotential of 0.9 V versus RHE. [29] O-vacancy confined in ZnO nanosheetsThe electrochemical conversion of CO 2 into hydrocarbons is an important approach to store sustainable energy and address climate concerns. However, it is a huge challenge to unearth a promising model for elucidating the role of dopants and vacancies on catalysts upon CO 2 electroreduction. Herein, porous indium oxynitride nanosheets with simultaneous incorporation of nitrogen dopant and oxygen vacancy (V o -N-InON) are reported for achieving efficient CO 2 conversion to formic acid (HCOOH). As a result, the catalyst exhibits an extremely high formate selectivity of 95.1% at a low potential of −0.8 V versus reversible hydrogen electrode (RHE) compared with pristine In 2 O 3 , V o -In 2 O 3 , and InN, delivering a large partial current density of 121.1 mA cm -2 for formate production at −1.13 V versus RHE in the flow cell. Density functional theory calculations reveal that the generation of *OCHO intermediate is the ratedetermining step. The synergistic effect between nitrogen dopants and oxygen vacancies contributes to the activation of CO 2 , facilitates the charge transfer, and reduces the reaction free energy of *OCHO protonation. This work not only discloses a fundamental understanding of synergistic effects between nitrogen dopants and oxygen vacancies to improve catalytic performance, but also provides an effective platform toward CO 2 conversion.

A topological chemical transition strategy of bismuth-based materials for high-efficiency electrocatalytic carbon dioxide conversion to formate

“… with strong bonding is more likely to bind to H + to form OCHO* intermediates, which is more conducive to the next reaction of the formation of the formate product. 46–48…”

“…CO *À 2 with strong bonding is more likely to bind to H + to form OCHO* intermediates, which is more conducive to the next reaction of the formation of the formate product. [46][47][48] Due to the limitation of the low CO 2 diffusion rate in H-type cells, the current density of specic products makes it difficult to meet the industry standard of 200 mA cm −2 . In this regard, a ow cell with faster CO 2 mass transmission is constructed to study the catalytic activity of the Bi 2 O 2 SO 4 catalyst for CO 2 reduction (Fig.…”

Electroreduction of CO2: Advances in the Continuous Production of Formic Acid and Formate

“…Definitions of the figures of merit are explained in Section . The last column shows the icon used to represent each study in the graphical representations of Figures –, according to the symbols and meanings detailed in Table . …”

Doping and pretreatment optimized the adsorption of *OCHO on bismuth for the electrocatalytic reduction of CO2to formate

“…10 Studies have shown that C1 is one of the most economical and feasible products for industrialization in the future, and formate can be widely used in textiles, pharmaceuticals, liquid hydrogen carriers, fuel cells and other fields. 11 Therefore, many catalysts such as Sb, 12 In, 13,14 Sn 15 and Bi 16 have been developed and constructed for the electrocatalytic reduction of CO 2 to formate.…”