News

Optical absorbance is used to study the kinetics of methylammonium lead iodide (MAPbI3) thin film degradation in response to combinations of moisture, oxygen, and illumination over a range of temperatures. 105 degradations were conducted over 41 unique environmental conditions. We discover that water acts synergistically with oxygen in a water-accelerated photo-oxidation (WPO) pathway. This pathway is the dominant pathway at 25 °C and is 10, 100, 1000, and >1000 times faster than dry photooxidation (DPO), degradation via hydrate formation, thermal degradation, and blue light degradation, respectively. We find that the rate determining step for DPO is proton abstraction from methylammonium while for WPO it is proton abstraction from water, which occurs at a faster rate and results in water acting as an accelerant for photooxidation of MAPbI3. A full kinetic rate equation is derived and fitted to the data to determine activation energies and rate constants. Find the preprint here.

Point-source electrochemical oxidation of source-separated urine is desirable, as it provides an avenue to destroy pharmaceuticals before dilution with wastewater. Here we have reported that the high urea content of fresh human urine suppresses the formation of oxychloride by inhibiting formation of HOCl/OCl‒ during electrolysis. While it still enables the oxidation of pharmaceuticals by •OH due to the slow rate of urea oxidation by •OH. This results in improved performance in each case when compared to equivalent treatment of synthetic hydrolyzed urine. Find the preprint here.

Dr. Tim Siegler won "Best Video Presentation" at the online nanoGe Meetup Conference "Beyond Lead Halide Perovskites: Synthesis and Applications of Metal Halide Semiconductors" for his poster on TlBr and Tl2AgBr3 nanocrystals. The presentation can be seen at this link. Congrats, Tim!

The Group welcomes Dr. Timothy (Tim) Siegler as a Postdoctoral Research Associate. Dr. Siegler received his Ph.D. in Chemical Engineering from the University of Texas at Austin in 2019 and his B.S. in Chemical Engineering from the University of Notre Dame. He has over 8 years of experience working in solution processed photovoltaics, having studied perovskite degradation and CdTe-perovskite tandems with Prof. Brian A Korgel at UT-Austin and quantum dot solar cell architectures under Prof. Prashant V Kamat at ND and Prof. Thomas Bein at LMU-Munich. Welcome, Tim!

Dr. Hillhouse presented the group's work on machine learning and perovskite degradation as an invited speaker at the NIHPO conference on perovskite solar cells, photonic and optoelectronics in Seville, Spain. This annual nanoGe conference brings together top researchers from around the world together to talk about recent developments in the field of perovskite optoelectronics.

In ACS Energy Letters, we report that use of linear machine learning models can be used to accurately forecast degradation-based evolution of PV device-relevant properties in perovskite thin films for a range of temperature, humidity, and illumination intensity. We also show these predictive models can be extended to devices by use of dark field microscope imaging. Link to Ryan and Wiley's paper.

Dr. Ryan Stoddard successfully defends his Ph.D. dissertation in the department of chemical engineering, entitled "Development of Stable, High Optoelectronic Quality Perovskites Using Photoluminescence, Photoconductivity, and Machine Learning". Congrats Dr. Ryan!

Graduate student Ryan Stoddard wins the UW Chemical Engineering Department's High Impact Paper Award for 2019, based on his recent highly-read publication in ACS Energy Letters on guanidinium-based wide band gap perovskites. See the announcement here. Congrats Ryan!

Undergraduate researcher Jason Moore was selected for a Mary Gates Research Scholarship this fall for his work on the optimization of the deposition of spray-coated hybrid perovskite thin-films. This makes him one of a handful of Mary Gates scholars at the University of Washington and one of three currently in the Hillhouse Group.

Dr. Jac Clark successfully defends his Ph.D. dissertation in the department of chemical engineering, entitled "Earth-Abundant Thin-Film Devices for Photovoltaic and Electrochemical Applications ". Congrats Dr. Jac!

The Group welcomes Dr. Wiley Dunlap-Shohl as a Postdoctoral Scholar. Dr. Dunlap-Shohl graduated from Dartmouth College in 2013 with a B.A. in Physics and a B.E. in Mechanical Engineering. After a brief period in industry during which he worked on the design of plasma-cutting equipment at Victor Technologies and compressed air energy storage at General Compression, he started his Ph.D. in Prof. David Mitzi's group at Duke University in 2014. There, he worked on the design of novel perovskite-inspired materials, device architectures, and processing schemes. Dr. Dunlap-Shohl received his Ph.D. in 2019, and is now working in the Hillhouse group on data-driven solutions to the halide perovskite stability problem.

Grad student Jac Clark has won a Bondermann Fellowship for travel to Cambodia, Vietnam, Laos, Thailand, India, Nepal, Peru, Bolivia, and Brazil. Find out more about Jac's travel plans and the Bondermann Fellowship here. Congrats Jac!

The U.S. Department of Energy's Solar Energy Technologies Office (SETO) selected the proposal "Machine-Learning Assisted Enhancement of Perovskite Stability and Performance" as part of its 2018 funding package, with a project budget of $1.9M. Read the announcement here.

Former Hillhouse Group Postdoc Dr. Alex Uhl has accepted a faculty position at the University of British Columbiain the Okangan School of Engineering. Congrats Alex! Find his group page here.

Photovoltaic (PV) device development is much more expensive and timeconsuming than the development of the absorber layer alone. This Perspective focuses on two methods that can be used to rapidly assess and develop PV absorber materials independent of device development. The absorber material properties of quasi-Fermi level splitting and carrier diffusion length under steady effective 1 Sun illumination are indicators of a material’s ability to achieve high VOC and JSC. These two material properties can be rapidly and simultaneously assessed with steady-state absolute intensity photoluminescence and photoconductivity measurements. As a result, these methods are extremely useful for predicting the quality and stability of PV materials prior to PV device development. Here, we summarize the methods, discuss their strengths and weaknesses, and compare photoluminescence and photoconductivity results with device performance for four hybrid perovskite compositions of various bandgaps (1.35-1.82 eV), CISe, CIGSe, and CZTSe. Link to Ian's article.

We have reported both external and internal photoluminescence quantum efficiency and quasi-Fermi-level splitting of surface-treated hybrid perovskite (CH3NH3PbI3) thin films. With respect to the material bandgap, these passivated films exhibit the highest quasi-Fermi-level splitting measured to date, reaching 97.1 ± 0.7% of the radiative limit, approaching that of the highest performing GaAs solar cells. We confirm these values with independent measurements of internal photoluminescence quantum efficiency of 91.9 ± 2.7% under 1 Sun illumination intensity, setting a new benchmark for these materials. These results suggest hybrid perovskite solar cells are inherently capable of further increases in power conversion efficiency if surface passivation can be combined with optimized charge carrier selective interfaces. Link to Ian's article

We have reported 1.84eV bandgap (FA0.33GA0.19Cs0.47)Pb(I0.66Br0.34)3 and 1.75eV bandgap (FA0.58GA0.10Cs0.32)Pb(I0.73Br0.27)3attain quasi-Fermi level splitting of 1.43eV and 1.35eV, respectively, which is >91% of the Shockley-Queisser limit for both cases. Films of 1.75eV bandgap (FA,GA,Cs)Pb(I,Br)3 are then used to fabricate p-i-n photovoltaic devices that have a VOC of 1.24 V. This VOC is among the highest VOC reported for any HPs with similar bandgap (1.7 to 1.8 eV) and a substantial improvement for the p-i-n architecture, which is desirable for tandems with Si, CIGS, or a low-bandgap HP. Link to Ryan's article.

We have reported that incorporate phenylethylammonium (PEA) in a mixed-halide perovskite composition to solve the inherent material-level challenges in 1.80–1.85 eV Egperovskites and the amount of PEA incorporation governs the topography and optoelectronic properties of resultant films. This article has set new record for photovoltage. Link to Adharsh & Ryan's article.

We have reported that a fullerene variant, Indene-C60 bis-adduct, is used to achieve optimized interfacial contact in a small-bandgap (˜1.2 eV) subcell, which facilitates higher quasi-Fermi level splitting, reduces nonradiative recombination, alleviates hysteresis instabilities, and improves Voc to 0.84 V. Compositional engineering of large-bandgap (˜1.8 eV) perovskite is employed to realize a subcell with a transparent top electrode and photostabilized Voc of 1.22 V. The resultant monolithic perovskite–perovskite tandem solar cell shows a high Voc of 1.98 V (approaching 80% of the theoretical limit) and a stabilized PCE of 18.5%. Link to Adharsh's article.

We have reported that a ligand-assisted crystallization (LAC) technique that introduces additives in situ during the solvent wash and developed a new method to dynamically measure the absolute intensity steady-state photoluminescence and the mean carrier diffusion length simultaneously. The measurements reveal four distinct regimes of material changes and show that photoluminescence brightening often coincides with losses in carrier transport, such as in degradation or phase segregation. Link to Ryan & Felix's article.

U.S. Secretary of Energy, Dr. Ernest Moniz, visited the laboratory to see the innovations on photovoltaic materials and solution processed solar cells. Our research has been funded by the U.S. Department of Energy's SunShot Initiative for the last five years, and Hillhouse team was selected by the SunShot program to highlight for the Secretary.

We have reported the effect of composition on optoelectronic quality and stability of hybrid perovskites in an upcoming issue of The Journal of Physical Chemistry C. By using a combinatorial spray coating apparatus, we explored thousands of compositions of hybrid perovskites, ranging from MAPbI3 to MAPBI2Br. Absolute Intensity Photoluminescence (AIPL) mapping was then used to determine the quasi-Fermi level splitting (QFLS) at each composition. We have found that QFLS increases as expected with band gap, reaching a maximum of 1.27 eV for Eg = 1.75 eV. Comparing the QFLS to the maximum theoretical QFLS at each Eg, we have determined that the optoelectronic quality decreases with band gap from 88% (Eg = 1.60 eV) to 82% (Eg = 1.84 eV). Link to Ian's article

We have reported record efficiency solution-processed CIS in an upcoming issue of Energy and Environmental Science. We have used benign solvent solution processes to achieve a CIS solar cell with 13.0% PCE. Careful exploration of the redox chemistry has identified high thiourea to metal ratios as leading to the best devices. Our optimized processing yields devices with Vocs (507 mV) close to those of state-of-the-art vacuum-processed absorbers (515 mV and 491 mV). This work marks a high-water mark for non-toxic solution processed CIS

Jac won the 1st Place Poster Prize in 8th Annual UW Chemical Engineering Graduate Student Symposium for his poster titled "Cu2ZnSn(S,Se)4 Solar Cells from Inks: Combinatorial Screening and High Efficiency Device Fabrication". Congratulations Jac!

John was awarded 2nd place in the oral presentation division of the 8th annual UW Chemical Engineering Graduate Student Symposium. He presented on his work "Illuminating the Potential of Solar Cells." The talk was well received by the audience, which included numerous professional attendees from local companies like Boeing and the Fred Hutchinson Cancer Research Center. He was described by one audience member as the "Bob Ross of PV". Congratulations John!

Dr. Alex Uhl won best poster prize at the 2015 EU-PVSC for his work entitled "Molecular-ink Route to 13.0% Efficient Low-bandgap CuIn(S,Se)2 and 14.7% Efficient Cu(In,Ga)(S,Se)2Solar Cells". Congratulations, Alex!

We have reported on the effect of Li-doping at the grain boundaries (GB) of CZTSSe in an upcoming issue of Physical Chemistry Chemical Physics. We show that Li inverts the electric field at grain boundaries in solution-processed CZTSSe, resulting in pushing the minority carriers away from the GB. Repelling the minority carriers effectively passivates the grain boundaries, allowing us to achieve devices with a non-hydrazine, solution-processed record of 11.8% PCE. Possible mechanisms are formation of LiCu, which reduces the concentration of less favorable ZnCu defects, and formation of LiZn defects, which are shallower than CuZn. Link to Hao's and Sarah's article.

We report the improvement of crystallinity and optoelectronic quality of methylammonium lead triiodide (MAPbI3) hybrid perovskites via VERG in an upcoming issue of The Journal of Physical Chemistry Letters. Solution processed planar films of MAPbI3 are often of poor quality - poor surface coverage, small grains, and large numbers of defects. We have developed a novel post-deposition treatment to correct morphology and optoelectronic quality. Treatment of films results in a large improvement in minority carrier lifetime, improving from 10 ns to over 200 ns. Link to Selin's article

We report the effect of CZTS nanocrystal reaction time on CZTSSe solar cells in an upcoming issue of Solar Energy Materials and Solar Cells. Longer reaction times yield nanocrystal with larger size and more compositional uniformity. This translates into devices with improved performance - better current collection, higher Voc, and higher efficiency. The larger grains also reduce the number of grain boundaries, limiting potential non-radiative recombination sites. Link to Andrew's article.

Our report of ligand-free CdS nanoparticles made in a sulfur copolymer matrix will be published in an upcoming issue of Chemical Communications. We have developed a procedure to synthesize CdS nanoparticles using a sulfur copolymer. The copolymer is simultaneously the S source and solvent, yielding ligand-free CdS nanoparticles. This allows us to avoid needing to remove any ligands before the CdS can be used. Link to Trevor's article.

John Katahara and Wesley Williamson joined other members of the UW Clean Energy Institute for the annual Paws-On-Science weekend at Pacific Science Center. These UW researchers fielded questions from members of the Puget Sound community on topics ranging from solar cells to next-generation batteries, as well as what Washington is doing with clean energy generation. Children were able to explore some of these concepts first-hand by building and racing solar cars.

Graduate students John Katahara, Jac Clark and undergraduate student Austin Miner volunteered their time in March for the 2015 Bryant Elementary School Science Fair. Over the course of 9 weeks, these members of the Hillhouse Group joined other researchers from UW in mentoring 4th/5th graders on basics of conducting scientific research. The science fair is an annual event.

We report the effects of reaction time on composition of kesterite nanocrystals synthesized by hot-injection in an upcoming issue of Chemistry of Materials. We have determined that short reaction times result in nanocrystal inks with large size and composition heterogeneity. Increasing reaction time narrows the size and stoichiometric variation, yielding inks with compositions near that of the starting precursors. We have also found that the choice of starting metal reagent only has a minor role in determining final ink composition. We can leverage this knowledge to produce kesterite nanocrystal inks with our desired off-stoichiometric compositions. Link to Andrew's article.

The results of a Hillhouse-Ginger Lab collaboration correlating nanoscale surface potential in solution-processed CZTSSe with local S/Se ratio is reported in an upcoming issue of Nano Letters. We have used scanning Kelvin probe microscopy (SPKM) to correlate local surface potential of CZTSSe films with local stoichometry from EDS. We have found that S-rich regions have more negative surface potentials, implying an increase in acceptor-like defect density. Link to article.

The Next Generation Photovoltaics 3 Program, which is part of the U.S. Department of Energy SunShot Initiative, supports the Hillhouse Group to explore the chemistry of high bandgap hybrid perovskites and develop novel tandem solar cells that utilize a hybrid perovskite as the top cell. Hillhouse and group member Ian Braly have patented unique tandem device architectures that may allow these solar cells to reach 30% efficiency. See the UW news article here.

We report the systematic investigation of native point defect chemistry in Cu2ZnSn(S,Se)4 and the effects of selected extrinsic dopants by spray coating films from DMSO-thiourea inks in an upcoming issue of the IEEE Journal of Photovoltaics. Over 6,000 unique compositions of Cu2ZnSn(S,Se)4 have been analyzed along with the effects of Cd, Fe, and Na doping. The most likely SRH-active defects appear to be defects and defect clusters involving SnZn, CuSn, and SnCu antisite defects, particularly the cluster [2CuZn + SnZn]. However, it is important to note that we observe high quasi-Fermi level splitting (QFLS) relative to the theoretical limit. In several regions, the ratio QFLS/QFLS,SQ is 0.69. This is higher than the ratio of the measured open circuit voltage to theoretical limit observed even in the record 12.6% efficient CZTSSe devices from hydrazine reported by IBM, which is 0.57. This suggests that the Voc still has significant room for improvement, even without changes to the material itself. While this is very positive, there is still a gap with respect to high efficiency devices from other materials. For instance the ratio of the measured Voc to theoretical Voc in 28.8% GaAs devices, 25.0% c-Si devices, 20.4% CIGSe devices, and 19.6% CdTe devices are 0.96, 0.80, 0.82, and 0.75, respectively. Link to Andrew's article.

A good photovoltaic material will also be a good radiative emitter. This may seem counter-intuitive at first since radiative recombination of excited carriers is a loss mechanism. However, the mechanism is always present, and it tends to be the slowest recombination pathway. Thus, if you turn off all the faster recombination pathways, you observe the photoluminescence. As a result, the magnitude and spectral character of the photoluminescence can reveal a lot about the inherent material quality and potential device performance. However, in many PV materials, even GaAs, sub bandgap states (Urbach tails and other phenomena) alter the spectral distribution of luminescence. This has hindered previous efforts to accurately extract the quasi-Fermi level splitting or reveal the character of the sub-bandgap states in materials like CIGS and CZTS. In an article to appear in the Journal of Applied Physics, we develop a new and general model of direct bandgap semiconductor absorption coefficients. We then use this model with a corrected Lasher-Stern-Wurfel equation (referred to as a non-equilibrium Planck emission law by some) to model photoluminescence. We validate the model and show a tremendous range of applicability to model PL data from GaAs, CIGS, and CZTS. We use the model to extract the quasi-Fermi level splitting and characterize the sub-bandgap "tail" states. The quasi-Fermi level splitting matches exactly to the measured open circuit voltage in devices fabricated from the materials. Link to John's article.

Austin Miner was one of only ~7 undergraduate students from the entire state who received the Washington Research Foundation Fellowship. The scholarship awards Austin $6000 to conduct research over the next three quarters. In the group, Austin has set-up an instrument that can map the photocurrent across a solar cell down to resolutions of 500 nm using two different excitation wavelengths. He is using this technique, called LBIC, to study copper zinc tin sulfoselenide (CZTS) solar cells.

Ian Braly won best poster this year at the International Conference on Energy Conversion and Storage (ORCAS). Ian reported the results of combinatorial experiments to develop high bandgap hybrid perovksite photovoltaic materials. Well done Ian!

What if we mass produced CZTS solar cells from the inks developed in the Hillhouse lab? How much will the ink cost? How much energy will it take to create the precursor chemicals? What are the waste products? Are there health and environmental risks? To help answer these questions, senior undergraduate chemical engineering students have designed the manufacturing plants to create the ink precursors as their capstone design project. The team is studying how the manufacturing plants could impact the surrounding environment and determine if there are better ways to process the materials. The researchers in this project are adding to previous research and developing the big picture of how the technology can be sustainable, healthy for people and the environment, and economically viable. Read more here.

Volunteers from the Hillhouse Group went out to the Pacific Science Center at the Seattle Center for a fun weekend of science education. Graduate students Ian Braly, John Katahara, and Wesley Williamson engaged children of all ages on matters related to solar energy, energy production, energy and resource conservation, as well as general scientific principles. Paws-On-Science weekend is an annual event.

The Group welcomes Dr. Alexander Uhl as a Postdoctoral Research Associate. Dr. Uhl received his Ph.D. in Material Science from the ETH in Zurich Switzerland in 2013 after completing his Diploma degree in Nanostructural Engineering from the University of Würzburg in Germany. He has over 6 years of experience in photovoltaics having worked with Prof. Marika Edoff and Prof. Ayodhya Tiwari on non-vacuum deposition of semiconductor layers. With financial support from the Swiss National Science Foundation (Project P2EZP2_152168), Dr. Uhl is now conducting his postdoctoral research at the University of Washington with the Hillhouse Group.

Both Andrew Collord and Ian Braly have won Exploratory Fellowships from the newly launched UW Clean Energy Institute. They will both receive funding for the next two quarters to pursue high-risk high-reward research projects

Governor Jay Inslee toured the Hillhouse lab to help launch the newly founded UW Clean Energy Institute. For more information see the UW CEI news page

Austin Miner has been awarded the Mary Gates Research Scholarship. The scholarship awards a $4000 award to Austin over two quarters.

Dr. Tosun received her first B.S. degree in Chemical Engineering from Istanbul Technical University in 2007. She earned a second B.S. in Materials Science and Engineering, also from Istanbul Technical University (2008). She joined Prof. Eray S. Aydil's group at the University of Minnesota for her PhD in Chemical Engineering. She worked on CIGS and CZTS based solar cells and related materials. After her graduation in June 2013, she joined Prof. Hugh W. Hillhouse's group at the University of Washington to pursue her career on Thin Film Photovoltaics as a Post-Doctoral Research Associate.

Several of our students joined other research groups from the University of Washington at Shoreline Community College for the NW Solar Fest 2013. Group members Ian Braly, Austin Minor, John Katahara, and Wesley Williamson joined other educators in teaching the public what a solar powered future could look like.

Dr. Hao Xin won best poster at the 2013 IEEE PVSC conference for her work entitled "8.3% Efficient Cu2ZnSn(S,Se)4 Solar Cells Processed from Environmentally Benign Solvent". Congratulations Hao!

The U.S. National Science Foundation has awarded PI Hillhouse and co-PIs Alison Cullen, Daniel Gamelin, Christine Luscombe, and Xiaodong Xu a $1.9M grant to explore a "Sustainable Pathway to Terawatt-Scale Solution-Processed Solar Cells from Earth Abundant Elements." For more information see the NSF Press Release and the UW ChemE news page.

Solar Fest is an annual event that brings together exhibitors, educators, and the public in a festival like environment with food, live music, and plenty of demonstrations. This year there were over 109 exhibitors at Solar Fest. The event is organized by the Shoreline Solar Project for the purpose of promoting the practical application of renewal energy and environmentally responsible practices to enhance the economic, ecological, and social environment of our community. This year Research Group members Cori Bucherl and John Katahara help teach folks about solar energy and what may be possible in the near future.

The Hillhouse Group moves into the brand new Molecular Engineering & Sciences (MolES) building. Other research groups that are also part of the new UW Molecular Engineering & Sciences Institute will be moving in throughout the summer. The entire first floor is dedicated to solar energy research and is home to the Advanced Materials for Energy Institute. The expansive basement is the new home to the Nanotechnology User Facility (NTUF) and has additional instrumentation space.

The M.J. Murdock Charitable Trust was created from the estate of Jack Murdock, co-founder of Tektronix. The Trust supports education, scientific research, and enrichment programs in the Pacific Northwest. The Trust awarded Hillhouse and UW colleagues an infrastructure grant to build a unique suite of solar energy materials deposition and characterization instruments.

Nanowerk.com features a news highlight focusing on research from Wooseok Ki on a new solution-processing method to form copper zinc tin sulfoselenide solar cells using non-toxic environmentally benign solvents. The full journal article appears in Advanced Energy Materials. Link to Wooseok's article.

The U.S. Department of Energy SunShot Initiative, whose goal is to develop solar cells that cost just $0.50 per watt, supports the Hillhouse Group with an award. With these funds the Hillhouse group will develop and use combinatorial methods with nanocrystals and molecular precursors to explore the defect chemistry and develop better copper zinc tin sulfoselenide solar cells made with novel inorganic inks.

The American Chemical Society reports that group member Grayson Ford's article is one of the Top 10 Most Read Articles in the journal Chemistry of Materials during the second quarter of 2011. The article reports the discovery that germanium may be used to effectively tune the bandgap of CZTSSe solar cells without degrading the optoelectronic quality of the material. This important phenomenon may let researchers create graded bandgap devices and reach higher efficiencies. Two other UW faculty have articles in the Top 10 list, Prof. Alex Jen and Prof. Sam Jenekhe, both related to solar energy materials. What does it mean? UW faculty are having a major impact on materials development to harness the power of the Sun. Link to Grayson's article.

Clemson University selects Prof. Hillhouse for their Outstanding Young Alumni Award for his contributions to research in energy conversion. Hillhouse will be presented with the award at the banquet on April 28 in Clemson, SC. Hillhouse graduated with a B.S. in Chemical Engineering from Clemson in 1995.

Group members pack-up the lab equipment and hand it over to the movers. After a brief separation and a few replacement purchases, researchers and equipment are reunited in Seattle, and the lab is back up and running.

National Geographic posts a new article titled "Shining Light on the Cost of Solar Energy." The piece pulls together thoughts from Prof. Hillhouse and researchers from GE, NREL, and several other institutions to understand the cost of solar energy.

Research Corporation for Science Advancement (RCSA) selects Hillhouse for the inaugural class of awardees of their Scialog Fellowship on Solar Energy Conversion. The award provides unrestricted funds for the Fellows to pursue high-risk high-reward ideas that may lead to breakthroughs in the conversion of solar energy into electricity or fuels.

After 8 wonderful years in the School of Chemical Engineering at Purdue University, Hillhouse accepts the Harry A. & Metta R. Rehnberg Endowed Chair Professorship at the University of Washington. The Rehnberg Chair was created in 1979 with a gift from Metta Rehnberg and was the first endowed professorship in Engineering at the University of Washington. While sadly leaving many good friends and colleagues at Purdue, he joins the ChemE Department at UW where he worked under Prof. John Berg 15 years ago. See the ChemE Departmental news item.