Nanoparticles make it easier to turn light into solvated electrons

Nanoparticles make it easier to turn light into solvated electrons

There are many ways to initiate chemical reactions in liquids, but placing free electrons directly into water, ammonia and other liquid solutions is especially attractive for green chemistry because solvated electrons are inherently clean, leaving behind no side products after they react.

In a published study in the Proceedings of the National Academy of Sciences, researchers from the Center for Adapting Flaws into Features (CAFF) uncovered the long-sought mechanism of a well-known but poorly understood process that produces solvated electrons via interactions between light and metal.

More links aren’t necessarily better for hybrid nanomaterials

More links aren’t necessarily better for hybrid nanomaterials

Chemists from Rice University and the University of Texas at Austin discovered more isn’t always better when it comes to packing charge-acceptor molecules on the surface of semiconducting nanocrystals.

Rossky, Roberts and colleagues at CAFF systematically studied hybrid materials containing lead sulfide nanocrystals and varying concentrations of an oft-studied organic dye called perylene diimide (PDI). The experiments showed that continually increasing the concentration of PDI on the surface of nanocrystals eventually produced a precipitous drop in electron transfer rates.

Prof. Martin Zanni awarded at FACSS SciX

Prof. Martin Zanni awarded at FACSS SciX

Marty Zanni (UWM)

Prof. Martin Zanni was granted the 2022 Ellis R. Lippincott award for his work in ultrafast infrared spectroscopy.

The award was jointly established in 1975 by The Optical Society (OSA), The Coblentz Society, and The Society for Applied Spectroscopy to honor the unique contributions of Professor Ellis R. Lippincott by recognizing an individual that has made significant contributions to the field of vibrational spectroscopy.

Dr. Charlisa Daniels invited to speak at GRC

Dr. Charlisa Daniels invited to speak at GRC

Charlisa Daniels (NKU)

CAFF partner Dr. Charlisa Daniels was invited to speak at the end of the 2022 Fundamentals of Separation Science and Engineering Gordon Research Conference in Ventura, CA on October 7, 2022!

Her talk was titled, “Understanding the Role of Stimuli Responsive Polymers in PPM Stationary Phases.”

Graduate Student Zach Armstrong Defends Thesis

Graduate student Zach Armstrong defends thesis

ZachArmstrong_Defense

Congratulations to Dr. Zach Armstrong for successfully defending his Ph.D. thesis entitled, “Ultrafast Two-Dimensional White-Light Spectroscopy of Excitons in Disordered Environments” October 7, 2022!

Excitons in semiconductors often experience disordered environments. Disorder can impact the energetics and relaxation dynamics on ultrafast timescales, both having implications for the operation of photovoltaics. In this dissertation, I study the impact of disorder on novel semiconductors using two-dimensional white-light (2DWL) spectroscopy and microscopy.

Dr. Armstrong will spend a season working as ski patrol before he begins a postdoctoral position at the University of Colorado.

Director Christy Landes awarded by ACS-GHS

Director Christy Landes awarded by ACS-GHS

Christy Landes Hightower Award

CAFF Director Prof. Christy Landes was given the 2022 Joe W. Hightower Award at the American Chemical Society – Greater Houston Section Awards Banquet on October 7, 2022.

The Hightower Award was established in 1969 to provide recognition for meritorious contributions to the welfare and distinction of the Greater Houston Section, as demonstrated by outstanding and significant contributions to education, research, Sectional service and/or service to the chemistry community.

Graduate Student Miriam Bohlmann Kunz Defends Thesis

Graduate student Miriam Bohlmann Kunz defends thesis

MiriamBohlmannKunz_Defense

Congratulations to Dr. Miriam Bohlmann Kunz for successfully defending her Ph.D. thesis entitled, “Ultrafast Pulse-Shaping Applied to Multi-Dimensional Spectroscopy and Novel Microscopy Methods” on August 26, 2022!

Semiconducting thin films are the building blocks of next generation photovoltaic devices. In many of these devices, energy transfer is necessary for creating a photocurrent from the initially excited electrons. Studying the energy transfer is a difficult task as it happens on the femtosecond to picosecond time scales and between grains that are 10 nanometers to 1 micrometer in diameter and layers that are hundreds of nanometers thick. The tools with both adequate spatial resolution and time resolution to resolve the energy transfer are limited. In this dissertation I will describe the use and development of methods to study the energy transfer within semiconducting thin films.

Graduate Student Alexander Al-Zubeidi Defends Thesis

Graduate student Alexander Al-Zubeidi defends thesis

Al-Zubeidi, Alexander_Rice

Congratulations to Dr. Alexander Al-Zubeidi for successfully defending his Ph.D. thesis entitled, “Plasmonic Hot Carrier-Driven Electrochemistry” on August 19, 2022!

The need for renewable energy has sparked widespread interest in photocatalysts, including systems based on plasmonic metal nanoparticles. To take advantage of these materials, a fundamental understanding of how plasmon-induced hot-carriers drive chemical reactions is needed. This work examines how different hot carrier distributions affect electrochemical reactions of plasmonic nanoparticles, and how applied electrochemical potentials can be used to modify the reactivity of hot carriers.

Dr. Al-Zubeidi accepted a postdoctoral research associate position with the Link Lab at Rice University.

Graduate Student Anastasiia Misiura Defends Thesis

Graduate student Anastasiia Misiura defends thesis

Nastya&Christy_Rice

Congratulations to Dr. Anastasiia Misiura for successfully defending her Ph.D. thesis entitled, “2D and 3D Single-Molecule Microscopy to Enhance Protein Chromatography” in Summer 2022!

To advance our understanding of underlying phenomena in a chromatographic column, 2D and 3D single-molecule techniques were utilized. We uncover the differences in protein motion in mobile phases, depending on salt concentration, and correlated the results to an ensemble chromatogram. We also demonstrate the importance of the combined influence of surface properties on adsorption-desorption kinetics of proteins to the stationary phase. Overall, we have shown that single-molecule methods can uncover the details of protein dynamics and transport at the nanoscale and relate them to ensemble chromatography and apply them to protein purification at-scale.

Graduate Student Behnaz Ostovar Defends Thesis

Graduate student Behnaz Ostovar defends thesis

Behnaz Ostovar

Link Group, Rice University

Congratulations to Dr. Behnaz Ostovar for successfully defending her Ph.D. thesis entitled, “Plasmon-Mediated Carrier Dynamics in Metal Nanoparticles and Hybrid Nanostructures” in Spring 2022!

In this thesis, I studied the optical properties and ultrafast dynamics of novel nanomaterials, including emerging aluminum nanostructures, gold nanorods, and novel gold nanorod-semiconductor core-shell heterostructures. I utilized single-particle microscopy and transient ultrafast spectroscopy techniques that allow for detailed investigation of transient dynamics and optical properties of individual nanoobjects.

Dr. Ostovar is currently an Optical Waveguide Grating Engineer and a Waferfab Manufacturing Process Development Engineer at Lumentum.

Graduate Student Daniel Cotton Defends Thesis

Graduate Student Daniel Cotton Defends Thesis

Congratulations to Dr. Daniel Cotton for successfully defending his Ph.D. thesis in Spring 2022! Daniel Cotton

Dr. Cotton accepted a postdoctoral position in the Dawlaty Group at the University of Southern California.

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NSF grant kicks off Center for Adapting Flaws into Features

The NSF Center for Adapting Flaws into Features (CAFF) is supported by the Centers for Chemical Innovation (CCI) Program of the Division of Chemistry.  Iron-age metallurgists learned that judicious addition of impurities (nickel, carbon, etc.) could transform a metal with poor materials properties (iron) into strong steel tools. Chemical impurities, ‘flaws’, can be detrimental in some situations and uniquely valuable in others, creating the desirable ‘features’ of a material.

In modern times, the development of silicon-based electronics exploited the same concept. CAFF’s overarching goal is to identify chemical flaws that hold promise, understand the structural and electronic properties that make those flaws uniquely influential, and then to demonstrate how the same structures can be amplified to macroscopic scales. CAFF will examine how the type, location, and sparsity of defects on atomic, nano- and microscales influence, in particular, optical materials chemistry. Broader impacts for CAFF include fast-tracking the democratization of undergraduate education and focusing on a constituency of chemists that have fallen between the cracks of public/K-12 outreach on the one hand, and undergraduate/graduate training on the other. Key will be to build a network of Community College partners that includes underrepresented urban and underserved rural communities. A diverse set of faculty and students with unique skill sets will be partners who can help form the future of American science.

Questions?