Carbon‐Confined Indium Oxides for Efficient Carbon Dioxide Reduction in a Solid‐State Electrolyte Flow Cell

Abstract

Developing robust electrocatalysts and advanced devices is important for electrochemical carbon dioxide (CO2) reduction toward the generation of valuable chemicals. We present herein a carbon‐confined indium oxide electrocatalyst for stable and efficient CO2 reduction. The reductive corrosion of oxidative indium to the metallic state during electrolysis could be prevented by carbon protection, and the applied carbon layer also optimizes the reaction intermediate adsorption, which enables both high selectivity and activity for CO2 reduction. In a liquid‐phase flow cell, the formate selectivity exceeds 90 % in a wide potential window from −0.8 V to −1.3 V vs. RHE. The continuous production of ca. 0.12 M pure formic acid solution is further demonstrated at a current density of 30 mA cm−2 in a solid‐state electrolyte mediated reactor. This work provides significant concepts in the parallel development of electrocatalysts and devices for carbon‐neutral technologies.

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

“…[ 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, [ 6–8 ] nitrides, [ 9 ] sulfides, [ 10,11 ] MOFs, [ 12–15 ] pure metal, [ 16,17 ] and single‐atom 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.…”

Metal–Organic Framework-Derived BiIn Bimetallic Oxide Nanoparticles Embedded in Carbon Networks for Efficient Electrochemical Reduction of CO2 to Formate

“…Compared with BiInO-0.43@C, the In 3d peak of BiInO-0.67@C shifted to higher binding energy (Figure 2c), illustrating that the valence state of In in BiInO-0.67@C was slightly higher. 51,52 In addition, the O 1s spectra are convolved into four peaks located at 534.13, 532.78, 531.78, and 530.08 eV, which can be assigned to the adsorbed oxygen species, In−O, OH (H 2 O), and Bi−O, respectively (Figure 2d). 53 It is found that both BiInO-0.67@C and BiInO-0.43@C have a certain amount of adsorbed oxygen, indicating that appropriate In doping is conducive to the generation of oxygen defects (Figure 2d).…”

Metal-organic framework nanocrystal-derived hollow porous materials: Synthetic strategies and emerging applications

“…presented a carbon-confined indium oxide electrocatalyst for efficient CO 2 RR toward the direct production of formic acid. 179 Experimental results showed that the formate selectivity exceeds 90% in a wide potential window from −0.8 to −1.3 V versus RHE in a liquid-phase flow cell. The high selectivity and activity for CO 2 RR benefited from the carbon protective layer preventing the reductive corrosion of indium oxide and the carbon layer, optimizing the adsorption of reaction intermediates.…”