Neal R. Armstrong Research Group

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Group Posters

"Electronically Wired" Semiconductor Nanoparticles: Toward Vectorial Electron Transport in Hybrid Materials and Solar Assisted Hydrogen Production

The Effect of PEDOT:PSS and ITO Treatment in Excitonic Solar Cells: A Nanoparticle Investigation

Organic Electronic Materials

Organic Solar Cells: Optimization for Enhanced Device Performance

Small Molecule Adsorption on Freshly Deposited ITO Thin Films For Greater Photovoltaic Efficiency

Modification of Transparent Conducting Oxides with Noble Metal Nanoparticles: Optimization of Work Function and Charge Injection

Invistigation of Nanoscale Morphology and Electrical Conductivity of Solution Processed H-Bonded Phthalocyanine Films: Progress Toward New Photovoltaic Materials

Nano-Textured Multi Junction Solar Cells

Characterizing and Modifing the ITO/Organic Interface: Organic Solar Cells

Surface Modification of Indium-Tin Oxide Electrodes With Gold Nanoparticles and Its Effect on Organic Photovoltaic Preformance

Photochemistry of CdSe Nanoparticle Thin Films Covalently Linked to Electron-Rich Thiophenes

Phosphonic Acid Modification of Indium-Tin Oxide Electrodes: Combined XPS/UPS/Contact Angle Studies

Chemical Sciences Building

CSB was completed fall of 2006

Group Photo April 2008 Front: Clayton Shalcross, Erin Ratcliff, Dana Alloway, Brian Zacher, Alex Veneman, Derek Mangelsdorf, Jeff Head, Dr. Neal Armstrong Rear: Judy Jenkins, Daniel Heubner, Mariola Macech, WeiNing Wang, Niranjani Kumaran, Diogenes Placencia, Amy Grfaham. More Group Pictures

RECENT RESEARCH HIGHLIGHTS:
	Recent studies of organic solar cells have focused on heterojunctions based on near-IR absorbing phthalocyanines (Pc) and C60, and the impact of phase changes of the Pc on photovoltaic performance. Increases in short-circuit photocurrent (J SC) are accompanied by changes in open-circuit photopotential (V OC), which correlated with changes in frontier orbital energy offsets, determined by UV-photoelectron spectroscopy (UPS).
Surface/interface characterization techniques, such as UPS/XPS and conducting tip AFM (C-AFM) are essential components of our research studies of organic/organic’ heterojunctions, and the heterojunctions between transparent conducting oxides (TCO) and organic films.
	We have recently demonstrated the formation of highly ordered phthalocyanine thin films, using solution deposition of Pcs with H-bonding side chains. C-AFM studies have allowed the elucidation of the conductivity per Pc layer – leading to formation of new PV devices based on these ordered materials.
We have recently shown that new photovoltaic poly(thiophene) materials can be grown, and nano-textured, via electrodeposition. Device performance is directly correlated with the degree of electrochemical doping of the polymer film.
	Semiconductor nanoparticles (e.g. CdSe) can be ligand-capped with electroactive functional groups, allowing for their electrochemical incorporation into polymer hosts. The resultant thin film materials can be used as photoelectrochemical catalysts for H 2-production, or as sensitizers in new hybrid material solar cells.
Organic light emitting diodes can be combined with organic photovoltaic detectors to create new chemical sensor platforms, emphasizing the convenience and simplicity of an all on-chip platform, where light source and detector are combined to do ATR spectrometry, refractometry and spectroscopy.
Current Research Funding:
“ Ultrathin Film Molecular Electronic Materials: Self-Organizing Discotic Mesophases and Organic Heterojunctions,” National Science Foundation.
“Critical Interfaces in Organic Solar Cell and High Energy Density Capacitor Nano-Materials,” Office of Naval Research.
“Electrochemically Wired” Semiconductor Nanoparticles: Toward Vectoral Electron Transport in Hybrid Materials –with Jeff Pyun, Scott Saavedra, Department of Energy, Basic Energy Sciences – Solar Hydrogen Initiative.
“Ion channel/membrane arrays on electroactive waveguides for biomolecular assays,” with Scott Saavedra, Craig Aspinwall, Sergio Mendes, Henry K. Hall, National Institutes of Health.
Member of the “Science and Technology Center for Materials and Devices for Information Technology Research,” Division of Materials Research -- National Science Foundation.
“Photosensitized Electron Transfer in Semiconductor Nanoparticle-Polymer Hybrid Materials,” with S. Scott Saavedra, Jeff Pyun, Arizona Research in Solar Energy (AzRISE).