Jeanne McHale

  1. Professor Emeritus



  • Ph.D. Physical Chemistry, 1979
    University of Utah
  • B.S. Chemistry, 1975
    Wright State University


Vibrational and electronic spectroscopy, especially resonance Raman spectroscopy, for the study of electron transfer, solvent dynamics, chromophore aggregation, and solar photoconversion. Optical and electronic properties of nanomaterials and self-assembled dye aggregates, studies of interfacial electron transfer, optical and electronic properties of semiconductor nanoparticles. Light-harvesting plant pigments for solar energy conversion.Prof. McHale received her Ph.D. in physical chemistry in 1979 from the University of Utah, where she worked with Prof. Jack Simons. She was a member of the chemistry faculty at the University of Idaho from 1980 until 2004, when she joined the chemistry faculty at Washington State University. She is a fellow in the American Association for the Advancement of Science and the author of Molecular Spectroscopy (Prentice-Hall, 1999). With co-editor Leah Bergman, she edited the recently published Handbook of Luminescent Semiconductor Materials (Taylor & Francis, 2011). The McHale lab specializes in the use of resonance Raman and photoluminescence spectroscopy for the study of molecules and nanomaterials with interesting optical and electronic properties. Fundamental quantum mechanical aspects of electron transfer in solution and in interfacial systems are a major focus of our experiments. We pioneered the use of resonance Raman spectroscopy to study molecular aspects of solvent dynamics in electron transfer. Our current major research interests are the following.

Carrier Transport and Surface Properties of Metal Oxide Nanoparticles

Our current research emphasis is on carrier transport and interfacial electron transfer in dye-sensitized solar cells (DSSCs). These novel photovoltaic cells are based on wide band gap semiconductors in nanoparticulate form, coated with visible-light absorbing dyes. DSSCs offer some potential advantages over the current silicon-based devices, but there are challenges to the realization of their environmental and economic advantages. We are using spectroelectrochemistry and novel preparations of nanocrystalline TiO2 to understand the molecular basis for trap states which influence carrier mobilities and interfacial redox chemistry.

Natural Plant Pigments for Solar Energy Conversion

We are also interested in finding alternatives to the expensive ruthenium-based dye sensitizers presently used in these solar cells, by exploring natural dyes from plants and flowers as potential sensitizers in solar photoconversion. We have recently explored a new class of plant pigments, called betalains, with much potential for pushing the efficiency of natural dye-based solar cells to higher values.

Biomimetric Light-Harvesting Aggregates

Dyes which absorb visible light strongly often have a tendency to self-aggregate, which can alter the optical and electronic properties. We are interested in the unique optical properties of the self-assemblies of water-soluble porphyrins. We are uncovering the molecular details which determine the hierarchal structure of these aggregates, and the nature of the intermolecular forces and excitonic couplings which lead to delocalized excited electronic states. Our long range goal is to control and exploit the hierarchal structure of light-harvesting aggregates to improve the efficiency of dye-based solar energy conversion.

Prof. McHale recently contributed a chapter, “Hierarchal Structure of Light-Harvesting Porphyin Aggregates,” to Vol. 2 of J-Aggregates, edited by T. Kobayashi and published by World Scientific Press, available at

Visit YouTube to see a video about our recent work on hierarchal light-harvesting aggregates.


  • “Spectroelectrochemical Photoluminescence of Trap States of Nanocrystalline TiO2 in Aqueous Media,” Fritz J. Knorr and Jeanne L. McHale, J. J. Phys. Chem. C 2013, 117, xxx.
  • “Comment on ‘Characterization of Oxygen Vacancy Associates within Hydrogenated TiO2: a Positron Annihilation Study,’ by Jiang, J. et al.,” Riley E. Rex, Fritz J. Knorr and Jeanne L. McHale, J. Phys. Chem. C 2013, 117, 7949-7951.
  • “Resonance Raman Spectra of Individual Excitonically Coupled Chromophore Aggregates,” Christopher C. Rich and Jeanne L. McHale, J. Phys. Chem. C 2013117, 10856-10865.
  • “Anomalous Reactivity of the Water Oxidation Catalyst, [(bpy)2Ru(OH2)]2O4+, in Nitrate-Containing Solutions,” Stull, J. A.; Britt, R. D.; McHale, J. L.; Knorr, F. J.; Lymar, S. V.; and Hurst, J. K., J. Am. Chem. Soc. 2012134, 19973-19976.
  • “Influence of Hydrogen-Bonding on Excitonic Coupling and Hierarchal Structure of a Light-Harvesting Porphyrin Aggregate,” Christopher C. Rich and Jeanne L. McHale, Phys. Chem. Chem. Phys. 201214, 2362-2375.
  • “Observation of Charge Transport in Single TiO2 Nanotubes by Microphotoluminescence Imaging and Spectroscopy,” Candy C. Mercado, Fritz J. Knorr, and Jeanne L. McHale, ACS Nano 20126. 7270-7280.
  • “Light-Harvesting Chromophore Aggregates and Their Potential for Solar Energy Conversion,” Jeanne L. McHale, invited Perspective. J. Phys. Chem. Lett. 20123, 587-597.
  • “Empirical Modeling of Nanoindentation of Vertically Aligned Carbon Nanotube Turfs using Intelligent Systems,” Al-Khedher, M.; Pezeshki, C.; McHale, J.; Knorr, F. Fullerenes, Nanotubes and Carbon Nanostructures 201220, 200–215.
  • “Photoluminescence of Dense Nanocrystalline Titanium Dioxide Thin Films: Effect of Doping and Thickness in Relation to Gas Sensing,” Candy C. Mercado, Zachary Seeley, Amit Bandyopadhyay, Susmita Bose, Jeanne L. McHale* ACS Applied Materials & Interfaces 20113, 2281-2288.
  • “Improved efficiency of betanin-based dye-sensitized solar cells,” Cody Sandquist and Jeanne L. McHale, J. Photochem. Photobiol. A 2011, 221, 90-97.
  • “Adaptive neuro-fuzzy modeling of mechanical behavior for vertically aligned nanotube turfs,” Al-Khedher, M.;Pezeshki, C.; McHale, J.; Knorr, F., J. Mater. Science &Tech. 201127, 301-308.
  • “Theory of Transition-Dipole Coupling in Dye-Sensitized Semiconductor Nanoparticles,” Gregary C. Zweigle and Jeanne L. McHale, J. Phys. Chem. C 2011, 115, 13696-13703.
  • “Resonance Raman Spectroscopy of Helical Porphyrin Nanotubes,” B. A. Friesen, C. C. Rich, U. Mazur, and J. L. McHale, J. Phys. Chem. C2010114, 16357.
  • “Trap State Photoluminescence of Nanocrystalline and Bulk TiO2: Implications for Carrier Transport,” C. C. Rich, F. J. Knorr, J. L. McHale,* Mater. Res. Soc. Symposium Proc. 20101268, EE03-08.
  • “Defect Photoluminescence of TiO2 Nanotubes,” C. C. Mercado, J. L. McHale, Mater. Res. Soc. Symposium Proc. 20101268, EE03-10.
  • “Differing HOMO and LUMO mediated conduction in a porphyrin nanorod,” B. A. Friesen, B. Wiggins, J. L. McHale, U. Mazur, and K. W. Hipps, J. Am. Chem. Soc. 2010132, 8554-8556.
  • “New Nanoscale Insights into the Internal Structure of Tetrakis(4-sulfonatophenyl)porphyrin Nanorods,” Benjamin A. Friesen, Krista A. Nishida, Jeanne L. McHale and Ursula Mazur, J. Phys. Chem. C 2009113, 1709-18.
  • Knorr, F. J.; Zhang, D.; McHale, J. L. “Influence of TiCl4 treatment on surface defect photoluminescence of pure and mixed-phase TiO2 ,” Langmuir 200723, 8686-8690.
  • Knorr, F. J.; Mercado, C. C.; McHale, J. L. “Trap State Distributions and Carrier Transport in Pure and Mixed Phase TiO2: Influence of Contacting Solvent and Interphasial Electron Transfer,” J. Phys. Chem. C 2008112, 12786-94.