Inorganic

Inorganic Chemistry Seminar: Dr. Ellen Matson, University of Rochester

Tue, 2019-01-08 00:00 - 01:00
Speaker: 

Dr. Ellen Matson

University of Rochester

 

Title: Polyoxovanadate-alkoxide clusters: Redox-active Scaffolds for the Multielectron Activation of Small Molecules
Abstract:  The development of alternative fuels from secure and sustainable resources is one the greatest environmental and economic challenge society faces today. To meet increased energy demands and mitigate rising atmospheric greenhouse gas levels, new carbon-neutral resources must be developed. The conversion of inert, abundant molecules, such as N2O and CO2, into chemical fuels (NH3 and CH3OH, respectively) represents an attractive solution, as energy is stored in chemical bonds of molecules that are easily transported as liquids. However, currently these fuels are produced through the activation of small molecules via heterogeneous processes conducted at extreme temperatures and pressures, requiring expensive, dedicated facilitiesResearch in the Matson Group focuses on using synthetic inorganic chemistry to address these issues related to energy storage and production. Toward accomplishing these goals, we are investigating the synthesis, characterization and reactivity of heterometallic polyoxovanadate-alkoxide clusters. These unique, multimetallic assemblies are generated in high yields via solvothermal reactions from simple molecular precursors. Notably, the polyoxovanadate subunit possesses a high degree of redox flexibility, rendering it ideal for supporting multielectron transformations of inert, gaseous substrates. Herein, we present our results related to the activation of small molecules across heterometal-functionalized polyoxovanadate-alkoxide clusters.   
 
Location: 

Carol Lynch Lecture Hall

Chemistry Complex

Host: Dr. Tomosn

inquires rvargas@sas.upenn.edu

Inorganic Chemistry Seminar: Dr. Brad P. Carrow, Princeton

Tue, 2019-02-05 12:00 - 13:00
Speaker: 

Brad P. Carrow

Location: 

Carol Lynch Lecture Hall

Chemistry Complex

Host: Dr. Schelter

title and abstract :TBA

inquires rvargas@sas.upenn.edu

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

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

Tue, 2018-10-16 12:00 - 13:00
Speaker: 

Dr. Amy Prieto

Title "Inexpensive, Efficient Approaches for Energy Production and Storage"

 

 We are interested in developing new synthetic methods for nanoscale materials with applications in energy conversion and storage. For this talk, I will focus first on using photovoltaic devices to produce energy, and in particular the synthesis and characterization of Cu2ZnSnS4 nanoparticles. The structure-property relationships for these particles can be significantly modified as the metal and chalcogen stoichiometries are tuned.  Second, I’ll discuss our efforts to develop new architectures for rechargeable Li-ion batteries for storing that energy. We are working to incorporate high surface area structures of a novel anode material into a new battery architecture wherein the current collector is conformally coated with an electrolyte made by electrochemical deposition, then surrounded by the cathode electrode. The significant advantage is that the diffusion length for Li+ between the cathode and anode will be dramatically reduced, which should lead to much faster charging rates. The general theme between both topics is the development of new synthetic methods for useful materials with an eye toward non-toxic, earth abundant chemicals and reasonable manufacturing methods.

 

 

M. C. Schulze, R. K. Schulze, A. L. Prieto "Electrodeposited thin-film CuxSb anodes for Li-ion batteries: Enhancement of cycle life via tuning of film composition and engineering of the film-substrate interface" J. Mater. Chem. A20186, 12708-12717.


 

M. Braun, L. Korala, J.  M. Kephart, and A. L. Prieto, “Synthetic Control of Quinary Nanocrystals of a Photovoltaic Material: The Clear Role of Chalcogen Ratio on Light Absorption and Charge Transport for Cu2ZnSn(S1-xSex)4”, ACS Appl. Energy Mater.2018 1(3), 1053-1059.


 

Location: 

Carol Lynch Lecture Hall

Chemistry Complex

Host: Dr Goldberg

inquires 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

Inorganic Chemistry Seminar; Dr. Xavier Roy, Columbia University

Tue, 2019-04-09 00:00 - 01:00
Speaker: 
Dr. Xavier Roy
Location: 

Carol Lynch Lecture Hall

Chemistry Complex

Host: Dr. Murray

Title & Abstract: TBA

inquiries rvargas@sas.upenn.edu

Inorganic Chemistry Seminar: Dr. Milton Smith, MSU

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

Dr. Milton Smith

 

 

Catalysts that Cleave C–H and N–H Bonds for Fine Chemical Synthesis and Energy Conversion

 

Catalytic transformations of C–H bonds are now common. This wasn’t always the case. Building from the first thermal, catalytic coupling of a borane and a hydrocarbon, our research group2 developed highly active iridium catalysts that exhibit unique regioselectivities for arene substitution and remarkable chemoselectivity for C–H functionalization. For example, sp2-C–X bonds (X = Cl, Br, and I) that are commonly cleaved in reactions with late transition metal complexes are remarkably inert to the Ir catalysts. From the roadmap we created many other groups in academia and industry have made important contributions to C–H borylations. Extensions to heterocyclic substrates and development of one-pot, catalytic reactions where the C–B bonds that result are further transformed make C–H borylation particularly attractive to synthetic chemists. Our recent work has emphasized ligand and reagent design to harness relatively weak interactions (e.g., hydrogen bonding) that are sufficiently strong to achieve  

C–H borylations with high regioselectivities.1,2

More recently, our research group has initiated a program to tap the potential for using ammonia to store, distribute, and release hydrogen gas. Specifically, we have targeted the oxidation ammonia to dinitrogen gas, protons, and electrons.3,4 Combining ammonia oxidation with ammonia synthesis from dinitrogen—the most abundant component of Earth’s atmosphere—and renewable hydrogen, a groundwork for a closed, zero-carbon fuel cycle based on nitrogen gas would be established. We recently have designed the first molecular catalyst that oxidizes NH3 to N2, six “protons,” and six electrons at room temperature. This is the anodic reaction in electrocatalytic NH3 “splitting” to N2 and H2.

 


 

 

(1) Chattopadhyay, B.; Dannatt, J. E.; Andujar-De Sanctis, I. L.; Gore, K. A.; Maleczka, R. E., Jr; Singleton, D. A.; Smith, M. R., III. J. Am. Chem. Soc. 2017, 139, 7864–7871.

(2) Smith, M. R., III; Bisht, R.; Haldar, C.; Pandey, G.; Dannatt, J. E.; Ghaffari, B.; Maleczka, R. E., Jr.; Chattopadhyay, B. ACS Catal. 2018, 8, 6216–6223.

(3) Little, D. J.; Smith, M. R., III; Hamann, T. W. Energy Environ. Sci. 2015, 8, 2775–2781.

(4) Little, D. J.; Edwards, D. O.; Smith, M. R., III; Hamann, T. W. ACS Appl. Mater. Interfaces 2017, 9, 16228–16235.

Location: 

Carol Lynch Lecture Hall

Chemistry Complex

Host: Dr. Mindiola

inquiries rvargas@sas.upenn.edu

Inorganic Chemistry Seminar: Dr. Katherine J. Franz, Duke

Tue, 2019-02-19 12:00 - 13:00
Speaker: 

Dr. Katherine Franz

Location: 

Carol Lynch Lecture Hall

Chemistry Complex

Host: Dr. Tomson/ Dmochowski

Title & Abstract TBA

inquires rvargas@sas.upenn.edu

Inorganic Chemistry Seminar: Dr. Michael Nippe, Texas A& M University

Tue, 2019-03-05 12:00 - 13:00
Speaker: 

Dr. Michael Nippe

Location: 

Carol Lynch lecture Hall

Chemistry Complex

Host: Dr. 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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