Controllable Synthesis of Few‐Layer Bismuth Subcarbonate by Electrochemical Exfoliation for Enhanced CO₂ Reduction Performance

Abstract

Two-dimensional (2D) engineering of materials has been recently explored to enhance the performance of electrocatalysts by reducing their dimensionality and introducing more catalytically active ones. In this work, controllable synthesis of few-layer bismuth subcarbonate nanosheets has been achieved via an electrochemical exfoliation method. These nanosheets catalyse CO reduction to formate with high faradaic efficiency and high current density at a low overpotential owing to the 2D structure and co-existence of bismuth subcarbonate and bismuth metal under catalytic turnover conditions. Two underlying fast electron transfer processes revealed by Fourier-transformed alternating current voltammetry (FTacV) are attributed to CO reduction at bismuth subcarbonate and bismuth metal. FTacV results also suggest that protonation of CO is the rate determining step for bismuth catalysed CO reduction.

Bismuthene for highly efficient carbon dioxide electroreduction reaction

“…For example, metal Bi, Bi single atomic 13 , Bi spherical nanoparticles 14,15 , Bi nanobelts 16 , thin films 17 , Bi nanowires 18 , and Bi 2 O 3 nanotubes 11 have been synthesized, but all with very limited CO2RR catalytic performance to HCOO − production. Two-dimensional (2D) multilayered Bi nanosheets with limited CO2RR performance [19][20][21] have also been synthesized recently with state-of-the-art synthesis methodologies, including, but not limited to, sonochemical exfoliation of bulk Bi 22 and in situ topotactic electroreduction of Bi precursors 23 . The monolayer Bi nanosheet (Bismuthene) was experimentally realized recently over templates such as SiC 20 and NbSe 2 24 , while the unsupported, stable, free-standing Bismuthene has never been synthesized before, but predicted and studied theoretically in the context of investigating its thermoelectric and other electronic properties [25][26][27][28] .…”

Two‐Dimensional Electrocatalysts for Efficient Reduction of Carbon Dioxide

“…Zhang et al. reported an electrochemical exfoliation method for the synthesis of few‐layered Bi 2 O 2 CO 3 NSs (BOCNS), which demonstrated excellent catalytic activity for the eCO 2 RR (Figure a) . Under electrochemical turnover conditions, this material is partially reduced to Bi to generate nanoscale interfaces between metallic Bi and Bi 2 O 2 CO 3 (Figure b).…”

“…c) FE values of formate, CO, and H 2 obtained by using a BOCNS electrode at designated applied potentials in a CO 2 ‐saturated 0.5 m aqueous solution of NaHCO 3 electrolyte. d) Long‐term stability test of a BOCNS electrode at an applied potential of −0.7 V versus RHE for 12 h. Reproduced with permission . Copyright 2018, Wiley‐VCH.…”

“…(Figure 9a). [92] Undere lectrochemical turnover conditions, this materiali sp artially reduced to Bi to generate nanoscale interfaces between metallicB ia nd Bi 2 O 2 CO 3 (Figure9b). The 2D structure and coexistence of Bi 2 O 2 CO 3 and metallic Bi contributed to the higher currentd ensity,l ower overpotential, and higher formates electivity achieved, compared with other Bi-based catalysts (Figure 9c,d).…”

A generalized amino-modification strategy to boost CO2 electroreduction current density of single-atom catalysts to industrial application level

“…1,2 Due to the stable binding of C=O bond in CO2 molecules, CO2 electrocatalytic reduction reaction (CO2RR) requires a high energy barrier, and moreover, the competitive hydrogen evolution reaction (HER) is more favored than CO2RR in kinetics. [3][4][5] Therefore, a large number of catalysts have been developed in the study of CO2RR in recent years, including metals and oxides, [6][7][8][9][10] nonmetal, [11][12][13][14][15] single-atom, 3,[16][17][18][19][20][21][22][23][24][25][26] and ultra-thin two-dimensional metal, [27][28][29] and molecule catalysts. 30 Among these catalysts, transition metal single-atom catalysts immobilized on nitrogen-doped carbon supports (M-N/C) exhibit good application prospects in CO2RR due to its high atom utilization efficiency and simple synthesis method.…”