Hydroxide Degradation Pathways for Substituted Benzyltrimethyl Ammonium: A DFT Study

Long, Hai; Pivovar, Bryan S.

doi:10.1149/2.0041501eel

Title: Hydroxide Degradation Pathways for Substituted Benzyltrimethyl Ammonium: A DFT Study

Abstract

The stability of cations used in the alkaline exchange membranes has been a major challenge. In this paper, degradation energy barriers were investigated by density functional theory for substituted benzyltrimethyl ammonium (BTMA+) cations. Findings show that electron-donating substituent groups at meta-position(s) of the benzyl ring could result in increased degradation barriers. However, after investigating more than thirty substituted BTMA+ cations, the largest improvement in degradation barrier found was only 6.7 kJ/mol. This suggests a modest (8×) improvement in stability for this type of approach may be possible, but for anything greater other approaches will need to be pursued.

Authors:

Long, Hai ^[1]; Pivovar, Bryan S. ^[1]

National Renewable Energy Lab. (NREL), Golden, CO (United States)

Publication Date:: Sat Nov 01 00:00:00 EDT 2014

Research Org.:: National Renewable Energy Lab. (NREL), Golden, CO (United States)

Sponsoring Org.:: USDOE Office of Science (SC)

OSTI Identifier:: 1166667

Report Number(s):: NREL/JA-2C00-62672
Journal ID: ISSN 2162-8726; MainId:23317;UUID:e1ac7055-612a-e411-b769-d89d67132a6d;MainAdminID:11793

Grant/Contract Number:: AC36-08-GO28308

Resource Type:: Accepted Manuscript

Journal Name:: ECS Electrochemistry Letters

Additional Journal Information:: Journal Volume: 4; Journal Issue: 1; Journal ID: ISSN 2162-8726

Publisher:: Electrochemical Society

Country of Publication:: United States

Language:: English

Subject:: 30 DIRECT ENERGY CONVERSION; 77 NANOSCIENCE AND NANOTECHNOLOGY; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; density functional theory (DFT)

Citation Formats


                    Long, Hai, and Pivovar, Bryan S. Hydroxide Degradation Pathways for Substituted Benzyltrimethyl Ammonium: A DFT Study.  United States: N. p., 2014. 
Web.  doi:10.1149/2.0041501eel.

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                    Long, Hai, & Pivovar, Bryan S. Hydroxide Degradation Pathways for Substituted Benzyltrimethyl Ammonium: A DFT Study.  United States.  https://doi.org/10.1149/2.0041501eel

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                    Long, Hai, and Pivovar, Bryan S. Sat .  
"Hydroxide Degradation Pathways for Substituted Benzyltrimethyl Ammonium: A DFT Study".  United States.  https://doi.org/10.1149/2.0041501eel.  https://www.osti.gov/servlets/purl/1166667.

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@article{osti_1166667,

  title        = {Hydroxide Degradation Pathways for Substituted Benzyltrimethyl Ammonium: A DFT Study},

  author       = {Long, Hai and Pivovar, Bryan S.},

  abstractNote = {The stability of cations used in the alkaline exchange membranes has been a major challenge. In this paper, degradation energy barriers were investigated by density functional theory for substituted benzyltrimethyl ammonium (BTMA+) cations. Findings show that electron-donating substituent groups at meta-position(s) of the benzyl ring could result in increased degradation barriers. However, after investigating more than thirty substituted BTMA+ cations, the largest improvement in degradation barrier found was only 6.7 kJ/mol. This suggests a modest (8×) improvement in stability for this type of approach may be possible, but for anything greater other approaches will need to be pursued.},

  doi          = {10.1149/2.0041501eel},

  journal      = {ECS Electrochemistry Letters},

  number       = 1,

  volume       = 4,

  place        = {United States},

  year         = {Sat Nov 01 00:00:00 EDT 2014},

  month        = {Sat Nov 01 00:00:00 EDT 2014}

}

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Works referencing / citing this record:

Density functional theory study on the degradation of fuel cell anion exchange membranes via removal of vinylbenzyl quaternary ammonium head group
journal, May 2020

Espiritu, Richard; Tan, John Lester; Lim, Len Herald
Journal of Physical Organic Chemistry, Vol. 33, Issue 5
DOI: 10.1002/poc.4049

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Title: Hydroxide Degradation Pathways for Substituted Benzyltrimethyl Ammonium: A DFT Study

Abstract

Citation Formats

Density functional theory study on the degradation of fuel cell anion exchange membranes via removal of vinylbenzyl quaternary ammonium head group journal, May 2020

Density functional theory study on the degradation of fuel cell anion exchange membranes via removal of vinylbenzyl quaternary ammonium head group
journal, May 2020