General

Biological Chemistry seminar: Abhinav Nath, University of Washington

Thu, 2018-11-01 15:00
Location: 

Carolyn Hoff Lynch Room

Topic: Protein molecular dynamics and health

Host: Dr. Elizabeth Rhoades

Biological Chemistry seminar: Kabirul Islam, University of Pittsburgh

Thu, 2018-10-18 15:00
Location: 

Carolyn Hoff Lynch Room

Topic: Chemical epigenetics

Host: Dr. E. James Petersson

Biological Chemistry seminar: Mya Suong, Johns Hopkins University

Thu, 2018-10-11 15:00
Location: 
Carolyn Hoff Lynch Room

Topic:  Single cell gene expression

Inorganic Chemistry Seminar: Dr. David Goldberg, Johns Hopkins University

Tue, 2019-02-26 12:00 - 13:00
Speaker: 
Dr. David Goldberg
Location: 

Carol Lynch Lecture Hall

Chemistry Complex

Host: Tomson

Title & Abstract TBA

inquires rvargas@sas.upenn.edu

Organic Chemistry Seminar: Dr. Andrew McNally, Colorado State University

Mon, 2018-11-12 12:00 - 13:00
Speaker: 

Dr. Andrew McNally

Location: 

Carol Lynch Lecture Hall

Chemistry Complex

Host: Dr. Walsh

Title & Abstract TBA

inquires rvargas@sas.upenn.edu

Inorganic Chemistry Seminar: Dr. Amy Prieto, Colorado State University

Tue, 2018-10-16 12:00 - 13:00
Speaker: 
Dr. Amy Prieto
Location: 

Carol Lynch Lecture Hall

Chemistry Complex

Host: Dr Goldberg

Title & Abstract: TBA

inquires rvargas@sas.upenn.edu

Physical Chemistry Seminar, Dr. Sanat Kumar, Columbia University

Thu, 2018-10-11 13:00 - 14:00
Speaker: 

Dr. Sanat Kumar

"Polymer-Grafted Nanoparticle Membranes with Controllable Free-Volume"

 

-Polymer based membranes play a key role in several industrially important gas separation technologies, e.g., removing CO2 from natural gas, with enormous economic and environmental impact. Baker advocates the development of novel membrane architectures since current, pure polymer membranes only offer limited systematic pathways for improvement. Here, we develop a novel hybrid membrane construct comprised entirely of nanoparticles grafted with polymers. These membranes are shown to have broadly tunable separation performance through variations in graft density and chain length. Computer simulations show that the optimal NP packing forces the grafted polymer layer to distort, yielding regions of measurably lower polymer density. Multiple experimental probes confirm that these materials have the predicted increase in “polymer free volume”, which explains their improved separation performance. These polymer-grafted NP materials thus represent a new template for rationally designing membranes with desirable separation abilities, coupled with improved aging characteristics in the glassy state and enhanced mechanical behavior.
Location: 
Carol Lynch Lecture Hall Chemistry Complex

Host: Dr. Fakhraai

 

inquires rvargas@sas.upenn.edu

 

Physical Chemistry Seminar, Dr. Paul Wennberg, Caltech

Thu, 2019-02-07 13:00 - 14:00
Location: 

Carol Lynch Lecture Hall

Chemistry Complex

Host: Dr. Lester

Title & Abstract TBA

Inquiries rvargas@sas.upenn.edu

Inorganic Chemistry Seminar, Dr. Hemamala Karunadasa, Stanford University

Tue, 2018-09-04 12:00 - 13:00
Speaker: 

Dr. Hemamala Karunadasa

Title

Between the sheets: The molecular chemistry of hybrid perovskites

Abstract

The tools of synthetic chemistry allow us to tune molecules with a level of precision not yet accessible with inorganic solids. We have investigated hybrid perovskites that couple organic small molecules with the optical and electronic diversity of extended inorganic solids. I will share our current understanding of these materials, whose technologically relevant properties are highly amenable to synthetic design.

The 3D lead-iodide perovskites have recently been identified as low-cost absorbers for high-efficiency solar cells. Although the efficiencies of devices with perovskite absorbers have risen at an impressive rate, the materials’ intrinsic instability and toxicity may impede their commercialization. I will discuss methods developed by our group to address these problems. The 2D hybrid perovskites have dramatically different properties from their 3D congeners. We discovered that some 2D perovskites emit broadband white light (similar to sunlight) when excited by UV light. I will discuss how these materials, which do not contain extrinsic dopants or obvious emissive sites, could emit every color of visible light. Although the organic molecules in hybrid perovskites have mostly played a templating role, we have investigated their role in engendering reactivity. I will describe reactions that occur between the inorganic sheets, which allow these nonporous solids to capture small molecules.

Brief Bio

Hema Karunadasa studied solid-state chemistry with Bob Cava at Princeton University and molecular catalysis with Jeff Long and Chris Chang at UC Berkeley and with Harry Gray at the California Institute of Technology. She joined Stanford Chemistry as an assistant professor in 2012. Her group synthesizes hybrid materials that harness the advantages of extended solids and discrete molecules.

Location: 

Carol Lynch Lecture Hall

Chemistry Complex

Attached Document: 

Host: Dr. Murray

inquiries rvargas@sas.upenn.edu

Inorganic Chemsitry Seminar: Dr. Matthew Kieber-Emmons, University of Utah

Tue, 2019-04-23 12:00 - 13:00
Speaker: 
Dr. Matthew Kieber-Emmons
Location: 

Carol Lynch Lecture Hall

Chemsitry Complex

Host: Tomson

Title & Abstract: TBA

inquiries rvargas@sas.upenn.edu

Department of Chemistry

231 S. 34 Street, Philadelphia, PA 19104-6323

215.898.8317 voice | 215.573.2112 fax | web@chem.upenn.edu

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