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Search Publications by: Dean DeLongchamp (Fed)

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Displaying 1 - 25 of 119

Self-Assembly of Hierarchical High-h Fluorinated Block Copolymers with an Orthogonal Smectic-within-Lamellae 3 nm Sub-Lattice and Vertical Surface Orientation

April 16, 2024
Author(s)
Bijal Patel, Hongbo Feng, Whitney Loo, Chad R. Snyder, Christopher Eom, Julia Murphy, Daniel Sunday, Paul Nealey, Dean DeLongchamp
Hierarchical structure-within-structure assemblies offer a route toward increasingly complex and multifunctional materials while pushing the limits of block copolymer self-assembly. We present a detailed study of the self-assembly of a series of

Quantitative relationships between film morphology, charge carrier dynamics, and photovoltaic performance in bulk-heterojunction binary vs. ternary acceptor blends

February 7, 2023
Author(s)
Weigang Zhu, Guoping Li, Subhrangsu Mukherjee, Natalia Powers-Riggs, Leighton Jones, Eliot Gann, R Joseph Kline, Andrew Herzing, Jenna Logsdon, Lucas Flagg, Charlotte Stern, Ryan Young, Kevin Kohlstedt, George Schatz, Dean DeLongchamp, Michael Wasielewski, Ferdinand Melkonyan, Antonio Facchetti, Tobin Marks
Addressing pertinent and perplexing questions regarding why nonfullerene acceptors (NFAs) promote higher power conversion efficiencies (PCEs) than traditional fullerenes and how photoactive bulk heterojunction (BHJ) film morphology, charge photogeneration

Non-fullerene acceptors with direct and indirect hexa-fluorination afford > 17% efficiency in polymer solar cells

December 22, 2021
Author(s)
Subhrangsu Mukherjee, Guoping Li, Liang-Wen Feng, Leighton Jones, Robert Jacobberger, Wei Huang, Ryan Young, Robert Pankow, Weigang Zhu, Norman Lu, Kevin Kohlstedt, Vinod Sangwan, Michael Wasielewski, Mark Hersam, George Schatz, Dean DeLongchamp, Antonio Facchetti, Tobin Marks
The rational molecular design of non-fullerene acceptors (NFAs) in organic solar cells (OSCs) can profoundly influence the photovoltaic (OPV) performance. To date, NFA fluorination has proven beneficial to cell performance. However, there is a lack of

Orientation of Thin Polyamide Layer-by-Layer Films on Non-Porous Substrates

December 16, 2021
Author(s)
Tawanda J. Zimudzi, Sarah E. Sheffield, Kathleen E. Feldman, Peter Beaucage, Dean DeLongchamp, Douglas I. Kushner, Christopher Stafford, Michael A. Hickner
The orientation of polyamide thin films on non-porous substrates was investigated using Fourier transform infrared (FTIR) spectroscopy and corroborated by near edge X-ray absorption fine structure (NEXAFS) measurements. Polyamide films comprised of m

Systematically Controlling Acceptor Fluorination Optimizes Hierarchical Morphology, Vertical Phase Separation, and Efficiency in Non-Fullerene Organic Solar Cells

November 21, 2021
Author(s)
Guoping Li, Xiaohua Zhang, Subhrangsu Mukherjee, Wei Huang, Ding Zheng, Liang-Wen Feng, Yao Chen, Jianglin Wu, Vinod Sangwan, Mark Hersam, Dean DeLongchamp, Junsheng Yu, Antonio Facchetti, Tobin Marks
Non-fullerene acceptor (NFA) end group (EG) functionalization, especially by fluorination, affects not only the energetics but also the morphology of bulk-heterojunction (BHJ) organic solar cell (OSC) active layers, thereby influencing the power conversion

Functional Oligothiophenes for Use in Self-Assembled Monolayer Field-Effect Transistors

October 12, 2021
Author(s)
A R. Murphy, Clayton Mauldin, J M. Frechet, Paul C. Chang, Kanan Putambekar, Kin-Yip Phoa, V Subramanian, Dean DeLongchamp, Daniel A. Fischer, Eric K. Lin
Asymmetric, end-functionalized thiophene oligomers capable of self-assembly and covalent bonding to silicon surfaces have been synthesized. Monolayer films were made using solution or Langmuir-Blodgett deposition techniques. Characterization of the films

Polarized X-ray scattering measures molecular orientation in polymer-grafted nanoparticles

August 12, 2021
Author(s)
Subhrangsu Mukherjee, Dean DeLongchamp, Eliot Gann, Daniel Sunday, Lee J. Richter, Jason Streit, Richard A. Vaia, Baskar Ganapathysubramanian, Kumar Saurabh, Adarsh Krishnamurthy
Polymer chains are attached to nanoparticle surfaces for many purposes, including altering solubility, influencing aggregation, dispersion, and even tailoring immune responses in drug delivery. The most unique structural motif of polymer-grafted

Orientational ordering within semiconducting polymer fibrils

May 2, 2021
Author(s)
Subhrangsu Mukherjee, Eliot Gann, Masrur M. Nahid, Terry McAfee, Andrew Herzing, Dean DeLongchamp, Harald W. Ade
Due to a general paucity of suitable characterization methods, the internal orientational ordering of polymer fibrils has rarely been measured despite its importance particularly for semi-conducting polymers. An emerging tool with sensitivity to bond

Systematic Merging of Nonfullerene Acceptor p-Extension and Tetrafluorination Strategies Affords Polymer Solar Cells with > 16% Efficiency

April 13, 2021
Author(s)
Subhrangsu Mukherjee, Dean DeLongchamp, Guoping Li, Xiaohua Zhang, Leighton Jones, Joaquin Alzola, Liang-Wen Feng, Weigang Zhu, Charlotte Stern, Junsheng Yu, Vinod K. Sangwan, Kevin L. Kohlstedt, Michael R. Wasielewski, Mark C. Hersam, George C. Schatz, Antonio Facchetti, Tobin Marks
The end-capping group (EG) is the essential electron-withdrawing component of nonfullerene acceptors (NFAs) in bulk heterojunction (BHJ) organic solar cells (OSCs). To systematically probe the impact of two frequent EG functionalization strategies, π

A NIST facility for Resonant Soft X-ray Scattering measuring nano-scale soft matter structure at NSLS-II

January 26, 2021
Author(s)
Eliot Gann, Glenn Holland, R Joseph Kline, Peter Beaucage, Dean DeLongchamp, Daniel A. Fischer, Brian Collins, Terry McAfee, Christopher McNeill, Thomas Crofts
We present the design and performance of a Resonant Soft X-ray Scattering (RSoXS) station designed for soft matter characterization built by the National institute of Standards and Technology (NIST) at the National Synchrotron Light Source-II (NSLS-II)

Experimental and Theoretical Evidence of Hydrogen Doping in Solution Processed Indium Gallium Oxide via Polymer Incorporation

July 23, 2020
Author(s)
Wei Huang, Joshua Tedesco, Po-Hsiu Chien, Kyle McMillen, Li Zeng, Subhrangsu Mukherjee, Binghao Wang, Yao Chen, Gang Wang, Yang Wang, Yanshan Gao, Michael Bedzyk, Dean DeLongchamp, Julia E. Medvedeva, Yan-Yan Hu, Tobin Marks, Antonio Facchetti
Aqueous solution processed high performance indium gallium oxide (IGO) thin-film transistors (TFTs) are realized by the simple addition of a hydroxyl (C-OH) containing polymer [polyvinyl alcohol (PVA)] into an IGO precursor solution. The field-effect

Crystallography, Morphology, Electronic Structure, and Transport in Non-Fullerene/Non-Indacenodithienothiophene Polymer:Y6 Solar Cells

July 22, 2020
Author(s)
Weigang Zhu, Subhrangsu Mukherjee, Joaquin Alzola, Vinod K. Sangwan, Samuel H. Amsterdam, Steven M. Swick, Leighton Jones, Michael Heiber, Guoping Li, Kevin L. Kohlstedt, Charlotte Stern, Dean DeLongchamp, Mark C. Hersam, George C. Schatz, Michael R. Wasielewski, Antonio Facchetti, Andrew Herzing, Lin Chen, Tobin Marks
Emerging nonfullerene acceptors (NFAs) with crystalline domains enable high-performance bulk heterojunction (BHJ) solar cells. Thermal annealing is known to enhance the BHJ photoactive layer morphology and performance. However, the microscopic mechanism of

Mixed-Flow Design for Microfluidic Printing of Two-phase Polymer Semiconductor Systems

July 9, 2020
Author(s)
Subhrangsu Mukherjee, Gang Wang, Liang-Wen Feng, Wei Huang, Yao Chen, Dengke Shen, Binghao Wang, Joseph Strzalka, Zheng Ding, Ferdinand Melkonyan, Jinhui Yan, J. Fraser Stoddart, Simone Fabiano, Dean DeLongchamp, Meifang Zhu, Antonio Facchetti, Tobin Marks
The rational creation of two-phase conjugated polymer systems with high levels of phase purity in each phase is challenging but crucial for realizing printed soft matter electronics. Here we report a mixed-flow microfluidic printing (MFMP) approach for two

Readily Accessible Benzo[d]thiazole Polymers for Nonfullerene Solar Cells with > 16% Efficiency and Potential Pitfalls

May 4, 2020
Author(s)
Liang-Wen Feng, Jianhua Chen, Subhrangsu Mukherjee, Yao Chen, Ding Zheng, Joseph Strzalka, Gang Wang, Dean DeLongchamp, Antonio Facchetti, Tobin Marks
Here we report facile, high-yield synthetic access to the difluoro BTA building block, 4,7-bis(5-bromo-4-(2-hexyl-decyl)-thiophen-2-yl)-5,6-difluoro-2-(pentadecan-7-yl)-benzo[d]thiazole (BTAT-2f), for use in donor (D)–acceptor 1 (A1)–D–acceptor 2 (A2)

Sub-picosecond charge-transfer at near-zero driving force in polymer:non-fullerene acceptor blends and bilayers

February 11, 2020
Author(s)
Yufei Zhong, Martina Causa, Gareth J. Moore, Philipp Krauspe, Bo Xiao, Jonas Kublitski, Rishi Shivhare, Johannes Benduhn, Eyal BarOr, Subhrangsu Mukherjee, Kaila Yallum, Julien R?hault, Stefan C. Mannsfeld, Dieter Neher, Lee J. Richter, Dean DeLongchamp, Frank Ortmann, Koen Vandewal, Erjun Zhou, Banerji Natalie, Florian Gunther
Organic photovoltaics based on non-fullerene acceptors (NFAs) show record efficiency of 16 to 17% and increased photovoltage owing to the low driving force for interfacial charge-transfer. However, the low driving force potentially slows down charge

Influence of Polymer Aggregation and Liquid Immiscibility on Morphology Tuning by Varying Composition in PffBT4T-2DT/Non-Fullerene Organic Solar Cells

January 29, 2020
Author(s)
Subhrangsu Mukherjee, Dean M. DeLongchamp, Regis J. Kline, Iain McCulloch, Zeinab Hamid, Andrew Wadsworth, Elham Rezasoltani, Sarah Holliday, Mohammed Azzouzi, Anne Guilbert, Yifan Dong, Marios Neophytou, Mark Little, Helen Bristow, Artem Bakulin, James Durrant, Jenny Nelson, Andrew A. Herzing
The temperature dependent aggregation behavior of PffBT4T polymers used in organic solar cells plays a critical role in the formation of a favorable morphology in fullerene-based devices. However, there has been little investigation into the impact of

Vapor deposition of a nonmesogen prepares highly structured organic glasses

October 22, 2019
Author(s)
Camille Bishop, Jacob L. Thelen, Eliot Gann, Michael F. Toney, Lian Yu, Dean DeLongchamp, Mark D. Ediger
We show that glasses with aligned smectic liquid crystal-like order can be produced by physical vapor deposition of a molecule without any equilibrium liquid crystal phases. Smectic-like order in vapor-deposited films was characterized by wide-angle X-ray

Photovoltaic Blend Microstructure for High Efficiency Post-Fullerene Solar Cells. To Tilt or Not To Tilt?

August 5, 2019
Author(s)
Subhrangsu Mukherjee, Dean M. DeLongchamp, Gang Wang, Steven M. Swick, Micaela Matta, Joseph Strzalka, Thomas Aldrich, Ferdinand Melkonyan, Antonio Facchetti, Tobin Marks, Jenna L. Logsdon, Simone Fabiano, Wei Huang, Tony Yang, Amod Timalsina, Natalia Powers-Riggs, Joaquin Alzola, Ryan M. Young, Michael R. Wasielewski, George C. Schatz
Achieving efficient polymer solar cells (PSCs) requires a structurally optimal donor–acceptor heterojunction morphology. Here we report the combined experimental and theoretical characterization of a benzodithiophene–benzothiadiazole donor polymer series

Stable Postfullerene Solar Cells via Direct C-H Arylation Polymerization. Morphology-Performance Relationships

May 16, 2019
Author(s)
Subhrangsu Mukherjee, Thomas Aldrich, Weigang Zhu, Lee J. Richter, Eliot Gann, Dean DeLongchamp, Antonio Facchetti, Ferdinand Melkonyan, Tobin Marks
The scope of the environmentally benign direct C-H arylation polymerization (DARP) process is validated and significantly extended in the synthesis of a high-performance benzodithiophene- based copolymer series, PBDT(Ar)-FTTE, with previously untested and

Advancing and Accelerating Materials Innovation: New Frontiers for the Materials Genome Initiative

April 5, 2019
Author(s)
Juan J. DePablo, Nicholas E. Jackson, Michael Webb, Long-Qing Chen, Joel Moore, Dane Morgan, Tresa M. Pollock, Darrell G. Schlom, Eric Toberer, James Analytis, Ismalia Dabo, Dean DeLongchamp, Fiete Gregory, Gregory Grason, Geoffroy Hautier, Yifei Mo, Krishna Rajan, Evan Reed, Efrain E. Rodriguez, Vladan Stevanovic, Jin Suntivich, Katsuo Thornton, Ji-Cheng Zhao
The Materials Genome Initiative (MGI) advanced a new paradigm for materials discovery, namely that the pace of materials discovery could be accelerated via complementary efforts in theory, computation, and experiment. Along with numerous successes, new

The Effects of Long Range Sidechain Ordering on Backbone Ordering and Optoelectronic Properties in Semiconducting Polymers

December 12, 2018
Author(s)
Joshua H. Carpenter, Masoud Ghasemi, Eliot Gann, Indunil Angunawela, Samuel Stuard, Liang Yan, Earl RItchie, Brendan O'Connor, Dean DeLongchamp, Harald Ade
Molecular ordering and packing greatly impacts the electronic and optoelectronic properties of semiconducting polymers. Despite much prior effort, the competing or synergistic ordering of the sidechains and aromatic cores has never been fully researched