Efficient and Selective CO₂ Reduction to Formate on Pd‐Doped Pb₃(CO₃)₂(OH)₂: Dynamic Catalyst Reconstruction and Accelerated CO₂ Protonation

Abstract

Exploring catalyst reconstruction under the electrochemical condition is critical to understanding the catalyst structure–activity relationship as well as to design effective electrocatalysts. Herein, a PbF2 nanocluster is synthesized and its self‐reconstruction under the CO2 reduction condition is investigated. F− leaching, CO2‐saturated environment, and application of a cathodic potential induce self‐reconstruction of PbF2 to Pb3(CO3)2(OH)2, which effectively catalyze the CO2 reduction to formate. The in situ formed Pb3(CO3)2(OH)2 discloses >80% formate Faradaic efficiencies (FEs) across a broad range of potentials and achieves a maximum formate FE of ≈90.1% at −1.2 V versus reversible hydrogen electrode (RHE). Kinetic studies show that the CO2 reduction reaction (CO2RR) on the Pb3(CO3)2(OH)2 is rate‐limited at the CO2 protonation step, in which proton is supplied by bicarbonate (HCO3−) in the electrolyte. To improve the CO2RR kinetics, the Pb3(CO3)2(OH)2 is further doped with Pd (4 wt%) to enhance its HCO3− adsorption, which leads to accelerated protonation of CO2. Therefore, the Pd‐Pb3(CO3)2(OH)2 (4 wt%) reveals higher formate FEs of >90% from −0.8 to −1.2 V versus RHE and reaches a maximum formate FE of 96.5% at −1.2 V versus RHE with a current density of ≈13 mA cm−2.

Sm and S Co‐doping to Construct Homo‐hetero Cu Catalysts for Synergistic Enhancing CO2 Electroreduction†

“…[ 20‐23 ] The ratio of HCO 3 – and CO 3 2– is related to the local H ion concentration, a higher ratio indicates a higher H ion concentration at the catalytic reaction interface, which is beneficial to the formation of the *OCHO species, which is the key intermediate for HCOOH formation. [ 24‐27 ] Compared with CuS 0.03 , the local H ion concentration of Sm 0.06 ‐Cu was significantly increased, indicating that the main driving force for inducing H enrichment near the active site came from the heterogeneously doped Sm 2 O 3 . In particular, the concentration of H ions was further increased on Sm 0.06 ‐CuS 0.03 .…”

Formate electrosynthesis from aqueous carbon dioxide over Pb–Zn catalysts with a core–shell structure

“…21 For example, Pd-doped Pb 3 (CO 3 ) 2 (OH) 2 prepared by Huang et al can reduce CO 2 with over 90% formate selectivity under a wide potential window. 22 Wang et al 23 synthesized Pb nanoparticles on copper nanowires, which hindered the hydrogen evolution reaction (HER) and increased the faradaic efficiency of formate (FE formate ) by 9.2%. In another study, Zheng et al 24 fabricated a single-atom Pb-alloyed copper catalyst (Pb 1 Cu), with the FE formate reaching 96%.…”

Oxygen vacancy stabilized Bi2O2CO3 nanosheet for CO2 electroreduction at low overpotential enables energy efficient CO‐production of formate

“…Nonetheless, the complex preparation process and poor anti‐oxidation of metal catalysts lead to a rapid decay in cyclability and delimited industrial applications 22–24 . Therefore, the major task is to develop an easily assembled yet antioxidative other metal–based catalysts with a comparable or even better electrocatalytic activity than that of metal electrocatalysts, including metal oxides, 12,25,26 sulfides, 27 nitrides, 28 and so on 29 …”

“…[22][23][24] Therefore, the major task is to develop an easily assembled yet antioxidative other metal-based catalysts with a comparable or even better electrocatalytic activity than that of metal electrocatalysts, including metal oxides, 12,25,26 sulfides, 27 nitrides, 28 and so on. 29 Particularly, Bi 2 O 2 CO 3 (BOC) has recently attracted tremendous attention for the electrochemical reduction of CO 2 -to-formate since the Bi O bond is beneficial to promote the reaction kinetics and selectivity of CO 2 in orthogonal symbiosis between [Bi 2 O 2 ] 2+ and [CO 3 ] 2À layer, which affords unique electronic structures and highly asymmetric intrinsic structure for modified catalytic properties. 30 Fortunately, Bi 2 O 2 CO 3 is easy to obtain by reconstructing Bibased precursors, such as Bi-MOF, 31 BiPO 4 , 20 Bi, 32 which undergoes surrounding reactants/products-mediated dissociation and conversion under working conditions.…”