(529f) 3D Layer-By-Layer Electrostatic Assembly of Graphene-Noble Metal Thin Films for Energy Storage and Conversion Applications

3D Layer-by-Layer Electrostatic Assembly of Graphene-Noble Metal Thin Films for Energy Storage and Conversion Applications

Mark H. Jaskot, Joshua M. Musiol, Kamil Woronowicz, Pamela L. Sheehan¹, Preston C. Haney¹, Harry L. Moore¹, F. John Burpo, Enoch A. Nagelli^*

Department of Chemistry & Life Science, Chemical Engineering Program

United States Military Academy, West Point, NY 10996

¹Explosive Ordnance Disposal, Demilitarization & Experimental Directorate, Army Futures

Command, RDECOM-ARDEC, Picatinny Arsenal, NJ

^*Corresponding PI: Dr. Enoch Nagelli, Email: enoch.nagelli@westpoint.edu

Carbon nanomaterials and noble metal nanoparticles constitute an ideal nanostructured composite platform for integration with other solid-state electrodes for energy storage and conversion applications. Self-assembly has been recognized as an effective strategy for the bottom–up synthesis of 3D macrostructures using graphene and CNTs as building blocks. However, all solution-based assembly techniques as a scalable platform for 3D thin film nanomaterials design have received limited attention. Here we propose a novel, simplistic, and scalable methodology utilizing a solution based electrostatic self-assembly technique for the formation of novel 3D noble metal nanoparticle composites with both graphene and carbon nanotubes. For example, graphene oxide and noble metal thin film nanocomposites were synthesized using electrostatic coordination between the carboxylic acid edge functional groups and platinum (Pt²⁺) or palladium (Pd²⁺) ions via substrate solution casting and spin coating. The chemical reduction of the resulting nanocomposite films formed transparent, conductive, and free-standing thin films comprised of interconnected graphene and platinum or palladium nanoparticles, held together with poly(methyl methacrylate) (PMMA). This solution-based platform materials design method allows for the controlled functionalization and assembly of any noble metal nanoparticles onto 2D graphene sheets or 1D CNTs while maintaining its 3D nanostructure with direction-specific and location-specific catalytic properties. In addition, this platform thin film approach can lead to the tunable design of multi-dimensional pillared nanocomposites via layer-by-layer (LBL) stacking of dissimilar PMMA-supported carbon nanomaterials functionalized with various noble metal nanoparticles demonstrating controlled macro-assembly of nanostructured films. This method of assembly from site-specific noble metal and carbon nanomaterial integration into multi-dimensional nanocomposite electrode thin films demonstrate the macro-scale control needed for the development of next generation miniaturized energy storage and conversion devices.