MOF‐Derived Cu/Bi Bi‐metallic Catalyst to Enhance Selectivity Toward Formate for CO₂ Electroreduction

Abstract

Converting CO2 into high‐value liquid products is a promising strategy to alleviate energy crisis. Herein, a novel Cu/Bi bi‐metal catalyst derived from MOFs has been prepared by a hydrothermal synthesis combining with high temperature calcination under N2 atmosphere, which shows cylindrical morphology composed of bi‐metallic nanoparticles. It is found that Cu/Bi bi‐metallic system is beneficial to lower the activate energy barrier of CO2 and shows a stronger adsorption capability for the CO2 ⋅ − intermediate than that of reference Bi/Bi2O3@C without Cu species. XPS analysis indicates the boosted performance for CO2 reduction reaction, which could be ascribed to synergistic coordination of Bi0 and Bi3+ in the catalyst. The optimized Cu1−Bi/Bi2O3@C exhibits excellent selectivity toward HCOOH with faradaic efficiency (FE) exceeding 84 % between −0.84 and −1.14 V vs. RHE, and even reaching 93 % at −0.94 V vs. RHE. The obtained Cu/Bi bi‐metal catalyst shows a promising application prospect in the CO2 reduction.

A hexacoordinated Bi3+-based ellagate MOF with acid/base resistance boosting carbon dioxide electroreduction to formate

“…The above results consistently indicate the high selectivity for HCOOH formation on SU-101, which corresponds well with the experimental results. This can be explained by two aspects: on one hand, the easier adsorption of CO 2 than H makes the CO 2 RR a more advantageous reaction than the HER; 35,36 on the other hand, the adsorption of CO 2 on SU-101 is not strong enough to weaken the C]O bond and thus the CO generation is not favourable.…”

Ag‐induced Phase Transition of Bi2O3 Nanofibers for Enhanced Energy Conversion Efficiency towards Formate in CO2 Electroreduction

“…As shown in Figure 2c, the Bi 4 f XPS spectrum of Bi 2 O 3 and Ag−Bi 2 O 3 were all deconvoluted into two separate components centred at 164.3 and 158.9 eV, which are ascribed to the Bi 3+ 4f 5/2 and Bi 3+ 4f 7/2 states [10,20] . The first of the O 1s region spectra of Bi 2 O 3 and Ag−Bi 2 O 3 in Figure 2d comprise three components with BEs of 532.7, 531.2, and 529.5 eV, which correspond to the adsorbed water on the surface, Bi(OH) 3 and Bi−O lattice oxygen, respectively [12,21] . The Bi−O lattice oxygen had a significantly higher area in the case of the Ag−Bi 2 O 3 nanofibers, suggesting more oxygen defects in Ag−Bi 2 O 3 compared to Bi 2 O 3 , indicating that more oxygen was introduced to the matrix of Ag−Bi 2 O 3 and could result in more active sites.…”

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

“…The characteristic peaks at 450.43 and 441.98 eV are attributed to In 0 , indicating the presence of metal In. Compared with BiInO-0.43@C, the In 3d peak of BiInO-0.67@C shifted to higher binding energy (Figure c), illustrating that the valence state of In in BiInO-0.67@C was slightly higher. , 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 d) . 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 d).…”

“…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). Additionally, XPS spectra of the single component materials (Bi 2 O 3 @C and In 2 O 3 @C) were tested for comparison with BiInO-0.67@C (Figure S10).…”