Corresponding Author

Jin-Li Qiao(qiaojl@dhu.edu.cn)


The electrochemical carbon dioxide reduction reaction (CO2RR) is a promising approach to produce liquid fuels and industrial chemicals by utilizing intermittent renewable electricity for mitigating environmental problems. However, the traditional H-type reactor seriously limits the electrochemical performance of CO2RR due to the low CO2 solubility in electrolyte, and high ohmic resistance caused by the large distance between two electrodes, which is unbeneficial for industrial application. Herein, we demonstrated a high-performance continuous flow membranes electrode assembly (MEA) reactor based on a self-growing Cu/Sn bimetallic electrocatalyst in 0.5 mol·L-1 KHCO3 for converting CO2 to formate. Compared with an H-type cell, the MEA reactor not only shows the excellent current density (66.41 mA·cm-2 at -1.11 VRHE), but also maintains high Faraday efficiency of formate (89.56%) with the steady work around 20 h. Notably, we also designed the new CO2RR system to effectively separate the gaseous/liquid production. Surprisingly, the production rate of formate reached 163 μmol·h-1·cm-2 at -0.91 VRHE with the cell voltage of 3.17 V. This study provides a promising path to overcome mass transport limitations of the electrochemical CO2RR and to separate liquid from gas products.

Graphical Abstract


electrochemical reduction, carbon dioxide, flow MEA reactor, electrolyzer

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[1] Daiyan R, Saputera W H, Masood H, Leverett J, Lu X Y, Amal R. A disquisition on the active sites of heterogeneous catalysts for electrochemical reduction of CO2 to value-added chemicals and fuel[J]. Adv. Energy Mater., 2020, 11(10): 1903796.

[2] Song R B, Zhu W, Fu J, Chen Y, Liu L, Zhang J R, Lin Y, Zhu J J. Electrode materials engineering in electrocatalytic CO2 reduction: energy input and conversion efficiency[J]. Adv. Mater., 2020, 27(32): 1902106.

[3] Yao Y, Wang J, Shahid U B, Gu M, Wang H J, Li H, Shao M H. Electrochemical synjournal of ammonia from nitrogen under mild conditions: current status and challenges, electrochem[J]. Energy Rev., 2020, 3(2): 239-270.

[4] Al-Mamoori A, Krishnamurthy A, Rownaghi A A, Rezaei F. Carbon capture and utilization update[J]. Energy Technology, 2017, 5(6): 834-849.
doi: 10.1002/ente.201600747 URL

[5] Kondratenko E V, Baltrusaitis G, Mul J, Larrazabal G O, Perez-Ramirez J. Status and perspectives of CO2 conversion into fuels and chemicals by catalytic, photocatalytic and electrocatalytic processes[J]. Energy & Environ. Sci., 2013, 6(11): 3112-3135.

[6] Jhong H R, Ma S C, Kenis P J A. Electrochemical conversion of CO2 to useful chemicals: current status, remaining challenges, and future opportunities[J]. Curr. Opin. Chem. Eng., 2013, 2(2): 191-199.
doi: 10.1016/j.coche.2013.03.005 URL

[7] Lu Q, Jiao F. Electrochemical CO2 reduction: Electrocatalyst, reaction mechanism, and process engineering[J]. Nano Energy, 2016, 29(SI): 439-456.
doi: 10.1016/j.nanoen.2016.04.009 URL

[8] Zheng X, Cai Z P, Li Y S. Data linkage in smart internet of things systems: A consideration from a privacy perspective[J]. IEEE Commun. Mag., 2018, 56(9): 55-61.

[9] Liu L X, Zhou Y, Chang Y C, Zhang J R, Jiang L P, Zhu W, Lin Y. Tuning Sn3O4 for CO2 reduction to formate with ultra-high current density[J]. Nano Energy, 2020, 77: 105296.
doi: 10.1016/j.nanoen.2020.105296 URL

[10] Li Q Q, Rao X F, Sheng J W, Xu J, Yi J, Liu Y Y, Zhang J J. Energy storage through CO2 electroreduction: A brief review of advanced Sn-based electrocatalysts and electrodes[J]. J. CO2 Util., 2018, 27: 48-59.

[11] Jiang X X, Wang X K, Liu Z J, Wang Q L, Xiao X, Pan H P, Li M, Wang J W, Shao Y, Peng Z Q, Shen Y, Wang M K. A highly selective tin-copper bimetallic electrocatalyst for the electrochemical reduction of aqueous CO2 to formate[J]. Appl. Catal. B: Environ., 2019, 259: 118040.
doi: 10.1016/j.apcatb.2019.118040 URL

[12] Xiong W, Yang J, Shuai L, Hou Y, Qiu M, Li X Y, Leung M K H. CuSn alloy nanoparticles on nitrogen-doped graphene for electrocatalytic CO2 reduction[J]. ChemEle-ctroChem, 2019, 6(24): 5951-5957.

[13] Chen A, Lin B L. A simple framework for quantifying ele-ctrochemical CO2 fixation[J]. Joule, 2018, 2(4): 594-606.
doi: 10.1016/j.joule.2018.02.003 URL

[14] Lee J, Lim J, Roh C W, Whang H S, Lee H. Electrochemical CO2 reduction using alkaline membrane electrode assembly on various metal electrodes[J]. J. CO2 Util., 2019, 31: 244-250.

[15] Ju W, Jiang F, Ma H, Pan Z, Zhao Y B, Pagani F, Rentsch D, Wang J, Battaglia C. Electrocatalytic reduction of gas-eous CO2 to CO on Sn/Cu-nanofiber-based gas diffusion electrodes[J]. Adv. Energy Mater., 2019, 9(32): 1901514.
doi: 10.1002/aenm.v9.32 URL

[16] Kim H Y, Choi I, Ahn S H, Hwang S J, Yoo S J, Han J, Kim J, Park H, Jang J H, Kim S K. Analysis on the effect of operating conditions on electrochemical conversion of carbon dioxide to formic acid[J]. Int. J. Hydrogen Energy, 2014, 39(29): 16506-16512.
doi: 10.1016/j.ijhydene.2014.03.145 URL

[17] Gabardo C M, O’Brien C P, Edwards J P, McCallum C, Dinh Y, Xu C T, Sargent J, Li E H, Sinton D. Continuous carbon dioxide electroreduction to concentrated multi-carbon products using a membrane electrode assembly[J]. Joule, 2019, 3(11): 2777-2791.
doi: 10.1016/j.joule.2019.07.021 URL

[18] Zhang F, Jin Z, Chen C, Tang Y, Mahyoub S A, Yan S, Cheng Z. Electrochemical conversion of CO2 to CO into a microchannel reactor system in the case of aqueous electrolyte[J]. Ind. Eng. Chem. Res., 2020, 59(13): 5664-5674.
doi: 10.1021/acs.iecr.9b07014 URL

[19] Yang H Z, Kaczur J J, Sajjad S D, Masel R I. Electrochemical conversion of CO2 to formic acid utilizing sustainion (TM) membranes[J]. J. CO2 Util., 2017, 20: 208-217.

[20] Larrazabal G O, Strom-Hansen P, Heli J P, Zeiter K, Therkildsen K T, Chorkendorff I, Seger B. Analysis of mass flows and membrane cross-over in CO2 reduction at high current densities in an MEA-type electrolyzer[J]. ACS Appl. Mater. Inter., 2019, 11(44): 41281-41288.
doi: 10.1021/acsami.9b13081

[21] Liu J Y, Peng L W, Zhou Y, Lv L, Fu J, Lin J, Guay D, Qiao J L. Metal-organic-frameworks-derived Cu/Cu2O catalyst with ultrahigh current density for continuous-flow CO2 electroreduction[J]. ACS Sustain. Chem. Eng., 2019, 7(18): 15739-15746.
doi: 10.1021/acssuschemeng.9b03892 URL

[22] Gong Q F, Ding P, Xu M Q, Zhu X R, Wang M Y, Deng J, Ma Q, Han N, Zhu Y, Lu J, Feng Z X, Li Y F, Zhou W, Li Y G. Structural defects on converted bismuth oxide nanotubes enable highly active electrocatalysis of carbon dioxide reduction[J]. Nat. Commun., 2019, 10(1): 2807.
doi: 10.1038/s41467-019-10819-4 URL

[23] Cifrain M, Kordesch K V. Advances, aging mechanism and lifetime in AFCs with circulating electrolytes[J]. J. Power Sources, 2004, 127: 234-242.
doi: 10.1016/j.jpowsour.2003.09.019 URL

[24] Peng L W, Wang Y X, Masood I, Zhou B, Wang Y F, Lin J, Qiao J L, Zhang F Y. Self-growing Cu/Sn bimetallic electrocatalysts on nitrogen-doped porous carbon cloth with 3D-hierarchical honeycomb structure for highly active carbon dioxide reduction[J]. Appl. Catal. B-Environ., 2020, 264: 118447.
doi: 10.1016/j.apcatb.2019.118447 URL

[25] Xiang H, Miller H A, Bellini M, Christensen H, Scott K, Rasul S, Yu E H. Production of formate by CO2 electrochemical reduction and its application in energy storage[J]. Sustain. Energ. Fuels, 2020, 4(1): 277-284.
doi: 10.1039/C9SE00625G URL

[26] Hatsukade T, Kuhl K P, Cave E R, Abram D N, Jaramillo T F. Insights into the electrocatalytic reduction of CO2 on metallic silver surfaces[J]. Phys. Chem. Chem. Phys., 2014, 16(27): 138-149.

[27] Burdyny T, Smith W A. CO2 reduction on gas-diffusion electrodes and why catalytic performance must be assessed at commercially-relevant conditions[J]. Energ. Environ. Sci., 2019, 12(5): 1442-1453.
doi: 10.1039/c8ee03134g



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