Aramid Nanofiber-Functionalized Graphene Electrodes for Structural - - PowerPoint PPT Presentation

Brick-and-Mortar Reduced Graphene Oxide / Aramid Nanofiber (rGO/ANF) Capacitors

• Electrodes made by vacuum filtration exhibit enhanced stiffness,

strength, and toughness because of the brick-and-mortar structure and hydrogen—bonding interfacial interactions

• A micromechanics model was developed using experimental
• bservations to investigate rGO waviness
• rGO and ANF waviness decreases the predicted elastic moduli
• Predicted waviness effect on conductivity is less significant

compared to that of elastic modulus

Aramid Nanofiber-Functionalized Graphene Electrodes for Structural Load- Bearing Energy Storage

Jodie L. Lutkenhaus, Dimitris Lagoudas, James Boyd, Micah Green, Texas A&M University Haleh Ardebili, University of Houston Overall Long-term Goal: To realize multifunctional structural capacitors and batteries that have enhanced mechanical properties, resulting in mass and volume savings. The unifying challenge in this area is to address both electrochemical and mechanical properties in a single multifunctional unit. Breakthrough Discoveries

Project Overview:

AFOSR Grant No. FA9550-16-1-0230 05/15/2016 – 05/14/2019

Aramid Nanofiber-Functionalized Graphene Electrodes for Structural Load- Bearing Energy Storage

Jodie L. Lutkenhaus, Dimitris Lagoudas, James Boyd, Micah Green, Texas A&M University Haleh Ardebili, University of Houston AFOSR Grant No. FA9550-16-1-0230 05/15/2016 – 05/14/2019 Effect of Random Orientation of rGO/ANF Nanomaterials

• An electrode of rGO sheets and ANFs in a randomly oriented

house of cards (HOC) 3D structure was realized experimentally

• Micah insert finding regarding mechanics and

electrochemical performance

• 3D-models were developed to investigate the effect of “house of

cards” architecture on ionic diffusivity

• Ionic diffusion creates a compression stress throughout

the geometry Impact of Interfacial Interactions Between rGO Sheets and ANFs

• Carboxylic acid (-COOH) and amine (-NH2) functionalized rGO

sheets exhibited enhanced hydrogen bonding with ANFs

• Mechanical properties were improved because of

hydrogen bonding (200% enhancement in strength, 33 MPa vs. 100 MPa for rGO vs rGO-NH2/25wt%ANF)

• Electrochemical properties were slightly diminished

because of defects introduced into rGO sheets

• Multifunctional efficiency shows a possible replacement for steel
• Modeling is needed to understand interphase

Aramid Nanofiber-Functionalized Graphene Electrodes for Structural Load- Bearing Energy Storage

Jodie L. Lutkenhaus, Dimitris Lagoudas, James Boyd, Micah Green, Texas A&M University Haleh Ardebili, University of Houston AFOSR Grant No. FA9550-16-1-0230 05/15/2016 – 05/14/2019 Electromechanical Coupling Effects - Induced Mechanical Stress

• rGO/ANF “brick and mortar” electrode resistance was

determined under bending-induced strain

• Electrode could undergo either mechanical annealing or

mechanical deformation

• Electromechanical model under development

Capacitors on a Kevlar Fiber Support

• An electrode with reduced graphene oxide coated Kevlar threads

was realized using sol-gel method experimentally

• The mechanical properties of Kevlar were retained,

capacitance was diminished Highlights of Future and Ongoing Work

• Data informatics approach to optimizing structural energy and

power

• A utility function was developed that mixes and matches

relevant energy and mechanical features

• Carbon nanotubes (CNTs) added to rGO/ANF electrodes are

being explored

• CNTs may enhance mechanical/electrical characteristics
• Examine dopamine as an interfacial enhancer for mechanical

properties

• Multifunctional modeling to capture coupling and

interrelationships of mechanical and electrochemical performance Products

1. Kwon, S.R., Harris, J., Zhou, T., Loufakis, D., Boyd, J.G., & Lutkenhaus, J.L., Mechanically Strong Graphene/Aramid Nanofiber Composite Electrodes for Structural Energy and Power. ACS Nano 11 (7), 6682-6690 (2017). 2. Kwon, S.R., Elinski, M.B., Batteas, J.D., & Lutkenhaus, J.L., Robust and Flexible Aramid Nanofiber/Graphene Layer-by-Layer Electrodes. ACS Applied Materials & Interfaces 9 (20), 17125-17135 (2017). 3. Parviz, D., Shah, S.A., Odom, M.G.B., Sun, W., Lutkenhaus, J.L., Green, M.J., “Tailored network formation in graphene oxide gels , Langmuir, accepted. 4. Aderyani, S., Flouda, P., Lutkenhaus, J., Ardebili, H., Architecture Influenced Ionic Diffusion in rGO/Aramid Nanofiber Structural Electrodes for Supercapacitors, Submitted. 5. Tianyang Zhou, James G. Boyd, Jodie L. Lutkenhaus, Dimitris C. Lagoudas, Micromechanics Modeling of the Elastic Moduli of ANF/rGO Nanocomposites, Submitted.