Sustainion Imidazolium‐Functionalized Polymers for Carbon Dioxide Electrolysis

CO2 electrolysis is a key step in CO2 conversion into fuels and chemicals as a way of mitigating climate change. We report the synthesis and testing of a series of new anion-conductive membranes (tradenamed Sustainion™) for use in CO2 electrolysis. These membranes incorporate the functional character of imidazolium-based ionic liquids as co-catalysts in CO2 reduction into a solid membrane with a styrene backbone. We find that the addition of an imidazolium group onto the styrene side-chains increases the selectivity of the reaction from approximately 25 % to approximately 95 %. The current at 3 V is increased by a factor of 14. So far we have been able to tune these parameters to achieve stable cells that provide current densities higher than 100 mA cm−2 at 3 V cell potential with a CO product selectivity over 98 %. Stable performance was observed for 6 months of continuous operation (>150 000 000 turnovers). These results demonstrate that imidazolium polymers are ideal membranes for CO2 electrolysis.

[1]  Xin Wang,et al.  A review on the electrochemical reduction of CO2 in fuel cells, metal electrodes and molecular catalysts , 2014 .

[2]  Shubo Wang,et al.  Hydroxide-ion induced degradation pathway for dimethylimidazolium groups in anion exchange membranes , 2014 .

[3]  Jilin Wang,et al.  Synthesis and characterization of novel anion exchange membranes containing bi-imidazolium-based ionic liquid for alkaline fuel cells , 2015 .

[4]  Anil Verma,et al.  Electrochemical conversion of CO₂ to fuels: tuning of the reaction zone using suitable functional groups in a solid polymer electrolyte. , 2014, Physical chemistry chemical physics : PCCP.

[5]  Guangwei He,et al.  Preparing alkaline anion exchange membrane with enhanced hydroxide conductivity via blending imidazolium-functionalized and sulfonated poly(ether ether ketone) , 2015 .

[6]  A. Lai,et al.  Highly ionic-conductive crosslinked cardo poly(arylene ether sulfone)s as anion exchange membranes for alkaline fuel cells , 2015 .

[7]  Youyong Li,et al.  Effects of substituents and substitution positions on alkaline stability of imidazolium cations and their corresponding anion-exchange membranes. , 2014, ACS applied materials & interfaces.

[8]  P. Kenis,et al.  Ionic Liquid–Mediated Selective Conversion of CO2 to CO at Low Overpotentials , 2011, Science.

[9]  M. Beller,et al.  Using carbon dioxide as a building block in organic synthesis , 2015, Nature Communications.

[10]  Anil Verma,et al.  Effect of solid polymer electrolyte on electrochemical reduction of CO2 , 2012 .

[11]  Anne C. Co,et al.  A review of the aqueous electrochemical reduction of CO2 to hydrocarbons at copper , 2006 .

[12]  Michele Aresta,et al.  Catalysis for the valorization of exhaust carbon: from CO2 to chemicals, materials, and fuels. technological use of CO2. , 2014, Chemical reviews.

[13]  A. Hollenkamp,et al.  Emerging electrochemical energy conversion and storage technologies , 2014, Front. Chem..

[14]  Y. Zhuo,et al.  Enhancement of hydroxide conductivity by grafting flexible pendant imidazolium groups into poly(arylene ether sulfone) as anion exchange membranes , 2015 .

[15]  Xun Lu,et al.  The effect of electrolyte composition on the electroreduction of CO2 to CO on Ag based gas diffusion electrodes. , 2016, Physical chemistry chemical physics : PCCP.

[16]  Yue Zhao,et al.  Imidazolium-based anion exchange membranes for alkaline anion fuel cells: elucidation of the morphology and the interplay between the morphology and properties. , 2016, Soft matter.

[17]  Jing Wang,et al.  A stable anion exchange membrane based on imidazolium salt for alkaline fuel cell , 2014 .

[18]  D. Dubois.  Development of molecular electrocatalysts for energy storage. , 2014, Inorganic chemistry.

[19]  Jun Mei,et al.  A facile functionalized routine for the synthesis of imidazolium-based anion-exchange membrane with excellent alkaline stability , 2016 .

[20]  Y. Hori,et al.  Electrochemical CO 2 Reduction on Metal Electrodes , 2008 .

[21]  R. He,et al.  Modification of poly(aryl ether ketone) using imidazolium groups as both pendants and bridging joints for anion exchange membranes , 2015 .

[22]  Anil Verma,et al.  Amines as Reaction Environment Regulator for CO2 Electrochemical Reduction to CH4 , 2015 .

[23]  Tae-Hyun Kim,et al.  Comb-shaped alkyl imidazolium-functionalized poly(arylene ether sulfone)s as high performance anion-exchange membranes , 2015 .

[24]  Wenjia Ma,et al.  1,2-Dimethylimidazolium-functionalized cross-linked alkaline anion exchange membranes for alkaline direct methanol fuel cells , 2015 .

[25]  Jiujun Zhang,et al.  A review of catalysts for the electroreduction of carbon dioxide to produce low-carbon fuels. , 2014, Chemical Society reviews.

[26]  M. I. Khan,et al.  Imidazolium functionalized anion exchange membrane blended with PVA for acid recovery via diffusion dialysis process , 2016 .

[27]  George A. Olah,et al.  Electrochemical CO2 Reduction: Recent Advances and Current Trends , 2014 .

[28]  R. Masel,et al.  Water Enhancement of CO2 Conversion on Silver in 1-Ethyl-3-Methylimidazolium Tetrafluoroborate , 2013 .

[29]  T. Meyer,et al.  Electrocatalytic Reduction of Carbon Dioxide: Let the Molecules Do the Work , 2015, Topics in Catalysis.

[30]  Maor F. Baruch,et al.  Substituent Effects in the Pyridinium Catalyzed Reduction of CO2 to Methanol: Further Mechanistic Insights , 2015, Topics in Catalysis.

[31]  R. Masel,et al.  In Situ Spectroscopic Examination of a Low Overpotential Pathway for Carbon Dioxide Conversion to Carbon Monoxide , 2012 .

[32]  Chenyi Wang,et al.  Stable poly(arylene ether sulfone)s anion exchange membranes containing imidazolium cations on pendant phenyl rings , 2016 .

[33]  H. Na,et al.  Comparison of alkaline stability of benzyltrimethylammonium, benzylmethylimidazolium and benzyldimethylimidazolium functionalized poly(arylene ether ketone) anion exchange membranes , 2016 .

[34]  A. Dibenedetto,et al.  Use of carbon dioxide as feedstock for chemicals and fuels: homogeneous and heterogeneous catalysis , 2014 .

[35]  Abass A. Olajire,et al.  Valorization of greenhouse carbon dioxide emissions into value-added products by catalytic processes , 2013 .

[36]  Jonas Baltrusaitis,et al.  Status and perspectives of CO2 conversion into fuels and chemicals by catalytic, photocatalytic and electrocatalytic processes , 2013 .

[37]  Rich Masel,et al.  Unlocking the Potential of CO2 Conversion to Fuels and Chemicals as an Economically Viable Route to CCR , 2014 .

[38]  Jiujun Zhang,et al.  Imidazolium-Functionalized Anion Exchange Polymer Electrolytes with High Tensile Strength and Stability for Alkaline Membrane Fuel Cells , 2015 .

[39]  F. Graf,et al.  Renewable Power-to-Gas: A technological and economic review , 2016 .

[40]  P. Kenis,et al.  Prospects of CO2 Utilization via Direct Heterogeneous Electrochemical Reduction , 2010 .

[41]  John-Paul Jones,et al.  Recycling of carbon dioxide to methanol and derived products - closing the loop. , 2014, Chemical Society reviews.

[42]  Claudio Ampelli,et al.  Electrocatalytic conversion of CO2 to liquid fuels using nanocarbon-based electrodes , 2013 .