Fabric Weave

Wearable Electronics

Created Using Vapor Phase Chemistry

Andrew Group 2016
DefyConvention

We Defy the Conventional

Using Chemistry

Wearable Electronics Lab

We are a cross-disciplinary research lab at UMass Amherst
producing emergent electronic technologies on unconventional substrates
using vapor deposition methods to acheive unmatched flexibility in device architectures, product assembly and manufacturing routines.

Lab Highlights

Glove

Smart Garments

Electrically Heated Glove
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Vapor Phase Chemistry

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Light Bulb


Conductive Textiles

Fabric Circuit Elements
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Thread Wall

Woven Electronics

Woven Mechanical Energy Harvesters (Triboelectrics)
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Test Fixture

Electrical Testing

Custom-Designed Fabrication and Testing Facilities
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SolarArray

Flexible Devices

& Diffuse-Light Operable Large Area Arrays
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Templating


Semiconductor Physics

Tuning Fundamental OptoElectronic Properties
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Photochromid Image

Photochromes

Beating the Fundamental Laws of Diffraction using Photochromes
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Dyes

Chromophore Synthesis

Synthesizing and Characterizing Open-Shell Organic Semiconductors
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Our Research

Monolithically-Integrated Textile Electronics

Unlike conventional substrates, such as glass, PET or paper, textiles are 3D microscaffolds displaying roughness and texture on multiple length scales.
3D Scaffold

Conformal coating techniques are integral for directly growing nanostructured devices from textile substrates.
We perform a small variety of vapor phase polymerization reactions to create films of conjugated polymers inside a reduced-pressure hot wall reactor.
One such example is the oxidative chemical vapor polymerization of EDOT to create PEDOT.
oCVD

This process creates stable, conformal films of a conducting polymer--PEDOT, in this case-- on arbitrary substrates, including various prewoven textiles.

PEDOT coated Fabrics

We use this vapor-phase deposition method to transform ordinary textiles into functional electronic devices. Our approach also minimizes the tremendous water pollution caused by traditional textile processing.
Some of our products are described below.

Textile/Thread Circuit Elements

We create highly-conductive fabrics and threads that are capable of acting as simple circuit elements while also being stable to wearing, laundering, ironing, stretching/tugging and rubbing.
Conductive Textiles

Activity-Tracking, Triboelectric Textiles

We use traditional textile manufacturing methods, such as knitting and weaving, to create fabric swatches that harvest mechanical energy to generate power!


Triboelectric Textiles

Smart Garments

We endeavor to seamlessly integrate electronic components, such as transistors, heating elements, diodes and capacitors into garments by coating familiar threads and clothing with electronically-active conjugated polymers.
Garment Heart Rate Monitor

Solar Harvesting Textiles

We are exploring multiple integrative approaches to create solar fabrics that preserve the breathability, pliability and durability of textiles.
Fabric Solar Cell

Vapor Phase Organic Chemistry

A suite of vapor-phase polymerization reactions performed inside a reduced-pressure hot wall reactor, collectively termed xCVD, are the enabling methods we use to build novel devices. In xCVD, films are formed directly on the substrate of interest as vapors of a chemical agent and precursor (or monomer) are introduced into an evacuated reactor chamber simultaneously, whereupon a polymer is formed in situ that subsequently coats arbitrary substrates placed in the polymerization region. This method allows for conformal coating of rough surfaces, with features resolvable down to 100-200 nm. The modularity of this technique ensures that careful monomer choice will lead to the in situ film growth of a host of conductive polymers displaying varied optoelectronic properties.


xCVD

Our current toolbox of xCVD reactions enable the fabrication of chemically well-defined thin films of p-doped PEDOT and proDOT, neutral poly(thiophene)s and poly(aniline)s onto arbitrary substrates with micro- and nano-scale features. We are working to expand our xCVD toolbox to include n-type conjugated polymer films and conductive polyradical films. Vapor phase chemical deposition of both metallic and semiconducting conjugated polymer and polyradical films are actively being explored.

Tuning the Optoelectronic Properties of Organic Crystals Using Graphene

Crystal orientation in organic thin films is one of the key parameters that determines interfacial energetics, absorption profiles and cross sections, exciton diffusion lengths, exciton dissociation efficiencies, and charge collection efficiencies. We use monolayer graphene to direct the crystal orientation of selected planar organic molecules, including p-type and n-type small-molecule semiconductors.

Lying-down orientation with π-stacking normal to the surface can be achieved with graphene templating. Additionally, graphene controls the out-of-plane alignment of all the molecules studied past the first monolayer and provides a driving force for confined in-plane growth.

Templating

Significant excitonic and electronic changes, including huge modulations in absorption profiles, total %light absorbed, Fermi levels, band edge values and CT state energies can be observed in the graphene-templated films, relative to films grown on oxide surfaces. Such changes can potentially increase the theoretical Voc expected for photovoltaic devices incorporating these templated films.

Xtal Porn

Transparent Organic Photovoltaic Devices and Flexible, Large-Area Arrays

New Materials for Visible-Transparent Electrodes, Nanostructured Optics to Optimize Light Collection,
and Circuit Design for Solar Cell Arrays Capable of Diffuse-Light Operation
TransparentTransparent

Subdiffraction Optical Lithography Enabled by Photochromes

Currently, nanomanufacturing is achieved via fast pattern-replication (nanoimprint lithography, optical-projection lithography, etc.) and is stymied by extremely slow pattern generation (scanning-electron-beam lithography). In other words, the time it takes to generate a new pattern is orders of magnitude longer than what it takes to simply replicate one.

Light offers significant advantages over charged particles for pattern generation. However, it suffers from one Achilles heel - diffraction. In the far field, the smallest focused spot that can be generated with light is limited to approximately half the wavelength.This, so called far-field diffraction limit or the Abbé limit, effectively prevents the use of long-wavelength photons (greater than 300nm) from patterning nanostructures less than 100 nm.

We have shown that optics, when combined with novel photochemistry, can result in deep sub-wavelength patterning with speeds that are far higher than with conventional approaches.

AMOL

Our idea is to record the nanoscale pattern in an ultra-thin or monolayer film comprised of photochromic molecules. These molecules undergo photoswitching between two isomeric forms, A and B. When isomer A absorbs a photon of wavelength 1, it turns into isomer B. When B absorbs photon of wavelength 2, it turns back to A. The binary nature of the switching process ensures that sub-diffraction-limited regions of B interspersed in A are formed.

In addition, we design the photochromic molecules such that B can be selectively converted in an irreversible manner to form C via a “locking” step, which allows us to create 3D patterns. These advances in pattern generation, when combined with continuous replication technologies such as roll-to-roll nanoimprint lithography can enable a new paradigm in high throughput top-down nanomanufacturing. In other words, organic photochromes can change the traditional process flow currently used to manufacture electronics!

Studying Spin Transport in Organic Semiconductors

Organic magnets, defined as primarily carbon-containing molecules, contain magnetic moments originating from the pi-molecular orbitals of each particular molecule. There are possibilities in organic magnets that are absent in the inorganic systems, such as flexibility, transparency, thin-film-forming ability, and low density, which allow unmatched control over processing conditions and make possible nontraditional device architectures on arbitrary substrates. Furthermore, the bulk optical, electrical and magnetic properties of organic materials display a remarkable sensitivity to molecular structure and intermolecular organization, allowing an informed researcher to rationally tune desired properties with amazing precision using chemical knowledge. In concert, all of these properties allow one to envision that electronic and spintronic devices on inexpensive and arbitrary substrates can, ultimately, be fabricated with high throughput using high-spin organic materials, leading to a suite of revolutionary nanostructured technologies that take advantage of both the charge and spin of an electron.

We are currently working to chemically-control and understand the magnetic properties of organic crystals, to integrate high-spin organic materials with inorganic semiconductors, and to fabricate transistors and spin valves using organic magnets.

First, we are working on generating a small library of novel organic diluted magnetic semiconductors. We prepared a new class of poly(thiophene)-based high-spin organic semiconductors and a new small-molecule bridging/linker moiety, tetrasubstituted indenofluorene, that demonstrate long-range spin polarization (as characterized by EPR) and maintain a rigidly-defined close packing of molecules, respectively. We are currently characterizing the emerging physical properties arising from spin-polaron and spin-exciton interactions in these materials.

Our major goal for the immediate future is to fabricate magnetic tunnel junction devices with our radical-containing molecules and to characterize magnetic field-dependent charge transport in these systems. Ongoing work involves investigation of various deposition techniques (physical vapor deposition, chemical vapor deposition, spincasting and self-assembled monolayers) to yield ordered thin films of organic radicals. We are also exploring various spectroscopic techniques to characterize the spin coherence lengths of our radical films.

Our Lab in the News

Our People

The research team that is making everything possible

Dr. Lushuai Zhang

Dr. Lushuai Zhang
Postdoctoral Associate

Jaejoon Kim

Dr. Jaejoon Kim
Postdoctoral Associate

Nongyi Cheng

Nongyi Cheng
Graduate Student
Chemistry
(UW-Madison)

Morgan Baima

Morgan Baima
Graduate Student
Chemistry

Linden Allison

Linden Allison
Graduate Student
Chemistry

Steven Hoxie

Steven Hoxie
Graduate Student
Chemistry

Trisha L. Andrew

Prof. Trisha L. AndrewPrincipal Investigator

Alumni

Dr. Yuelin Peng

Dr. Yuelin Peng
Electrical Engineering Ph.D.
Now @ Alta Devices

Greg Eyer

Greg Eyer
Chemistry M.Sc.

Dr. Jingjing Zhang

Dr. Jingjing Zhang
Former Postdoc
Now @ Argonne National Lab

Dr. Brandon Kobilka

Dr. Brandon Kobilka
Former Postdoc
Now @ IBM Tuscon

Wei Li

Wei Li
Materials Science M.Sc.

Nolan Blythe

Nolan Blythe

Ben Pollock

Ben Pollock

Nick Myllenbeck

Nick Myllenbeck
Now @ LBNL

Our Sponsors

Sponsors Sponsors SponsorsSponsors SponsorsSponsorsSponsorsSponsors

Our Publications

(click on the picture to get the article and related information from the publisher or the PDF link to directly download the article)

2017

Rugged Textile Electrodes for Wearable Devices Obtained by Vapor Coating Off-the-Shelf Plain-Woven Fabrics


Lushuai Zhang, Marianne Fairbanks, Trisha L. Andrew*
Adv. Funct. Mater. 2017, DOI:10.1002/adfm.201700415. PDF


Read the Advanced Science News Highlight

Read the UMass Amherst Research Spotlight

Read the Research Next Feature on our work


Vapor Phase Organic Chemistry to Deposit Conjugated Polymer Films on Arbitrary Substrates


Nongyi Cheng, Lushuai Zhang, Jae Joon Kim, Trisha L. Andrew*
J. Mater. Chem. C 2017, 5, 5787-5796. DOI:10.1039/C7TC00293A. PDF


Towards Seamlessly-Integrated Textile Electronics: Methods to Coat Fabrics and Fibers with Conducting Polymers for Electronic Applications


Linden Allison, Steven Hoxie, Trisha L. Andrew*
Chem. Commun. 2017, 53, 7182-7193. DOI:10.1039/C7CC02592K. PDF


Integrating a Semitransparent, Fullerene-Free Organic Solar Cell in Tandem with a BiVO4 Photoanode for Unassisted Solar Water Splitting


Yuelin Peng, Gokul Govindaraju, Dong Ki Lee, Kyoung-Shin Choi,* Trisha L. Andrew*
ACS Applied Materials and Interfaces 2017, DOI:10.1021/acsami.7b04486. PDF




ITO-Free Transparent Organic Solar Cell with Distributed Bragg Reflector for Solar Harvesting Windows


Yuelin Peng, Lushuai Zhang, Nongyi Cheng, Trisha L. Andrew*
Energies 2017, 10, 707. DOI:10.3390/en10050707. PDF


Read the Research Spotlight on Dr. Yuelin Peng's work


Triplet Exciton Dissociation and Electron Extraction in Graphene-Templated Pentacene Observed with Utrafast Spectroscopy


Thomas J. McDonough, Lushuai Zhang, Susmit Singha Roy, Nicholas M. Kearns, Michael S. Arnold, Martin Zanni*, Trisha L. Andrew
Phys. Chem. Chem. Phys. 2017, 19, 4809-4820. DOI:10.1039/C6CP06454J. PDF


Synthesis and Properties of Dithiocarbamate-Linked Acenes


Jingjing Zhang, Nicholas R. Myllenbeck, Trisha L. Andrew*
Org. Lett. 2017, 19, 210-213. DOI:10.1021/acs.orglett.6b03492. PDF


2016

All-Textile Triboelectric Generator Compatible with Traditional Textile Process


Lushuai Zhang, Yanhao Yu, Gregory P. Eyer, Guoquan Suo, Liz Anna Kozik, Marianne Fairbanks, Xudong Wang, Trisha L. Andrew*
Adv. Mater. Technol. 2016, 1600147. PDF


Orientation Control of Selected Organic Semiconductor Crystals Achieved by Monolayer Graphene Templates


Lushuai Zhang, Susmit Singha Roy, Nathaniel S. Safron, Melinda J. Shearer, Robert M. Jacobberger, Vivek Saraswat, Robert J. Hamers, Michael S. Arnold, Trisha L. Andrew*
Adv. Mater. Interfaces 2016, 1600621. PDF


Improved Photovoltaic Response of a Near-Infrared Sensitive Solar Cell by a Morphology-Controlling Seed Layer


Lushuai Zhang, Trisha L. Andrew*
Org. Electron. 2016, 33, 135-141. PDF


Color-Pure Violet-Light-Emitting Diodes Based on Layered Lead Halide Perovskite Nanoplates


Dong Liang, Yuelin Peng, Yongping Fu, Melinda J. Shearer, Jingjing Zhang, Jianyuan Zhai, Yi Zhang, Robert J. Hamers, Trisha L. Andrew*, Song Jin*
ACS Nano 2016, 10, 6897-6904. PDF


Reverse-Absorbance-Modulation-Optical Lithography for Optical Nanopatterning at Low Light Levels


Apratim Majumder, Xiaowen Wan, Farhana Masid, Benjamin J. Pollock, Trisha L. Andrew*, Olivier Soppera, Rajesh Menon*
AIP Adv. 2016, 6, 065312. PDF


A Comprehensive Simulation Model of the Performance of Photochromic Films in Absorbance-Modulation-Optical-Lithography


Apratim Majumder, Phillip L. Helms, Trisha L. Andrew*, Rajesh Menon*
AIP Adv. 2016, 6, 035210. PDF


2015

Molecular Orientation-Dependent Interfacial Energetics and Built-in Voltage Tuned by a Template Graphene Monolayer


Lushuai Zhang, Susmit Singha Roy, Robert J. Hamers, Michael S. Arnold, Trisha L. Andrew*
J. Phys. Chem. C 2015, 119, 45-54. PDF


Restricting the Ψ Torsion Angle Has Stereoelectronic Consequences on a Scissile Bond: An Electronic Structure Analysis


Eric R. Strieter* and Trisha L. Andrew*
Biochemistry 2015, 54, 5748-5756. PDF


Barrier-Free Absorbance Modulation for Super-Resolution Optical Lithography


Apratim Majumder, Farhana Masid, Benjamin J. Pollock, Trisha L. Andrew*, Rajesh Menon*
Opt. Express 2015, 23, 12244-12250. PDF


Development of Lead Iodide Perovskite Solar Cells Using Three-Dimensional Titanium Dioxide Nanowire Architectures


Yanhao Yu, Jianye Li, Dalong Geng, Jialiang Wang, Lushuai Zhang, Trisha L. Andrew, Michael S. Arnold, Xudong Wang*
ACS Nano 2015, 9, 564-572. PDF


Observing Electron Extraction by Monolayer Graphene Using Time-Resolved Surface Photoresponse Measurements


Lushuai Zhang, Susmit Singha Roy, Caroline R. English, Robert J. Hamers, Michael S. Arnold, Trisha L. Andrew*
ACS Nano 2015, 9, 2510-2517. PDF


2014

High Open-Circuit Voltage, High Fill Factor Single-Junction Organic Solar Cells


Yuelin Peng, Lushuai Zhang, Trisha L. Andrew*
Appl. Phys. Lett. 2014, 105, 083304. PDF


Patterning via Optical Saturable Transitions - Fabrication and Characterization


Precious Cantu, Trisha L. Andrew* Rajesh Menon*
J. Vis. Exp. 2014, 94, e52449. Link


Patterning via Optical-Saturable Transformations: A Review and Simple Simulation Model


Precious Cantu, Trisha L. Andrew* Rajesh Menon*
Appl. Phys. Lett. 2014, 105, 193105. PDF


2013

Effect of Synthetic Accessibility on the Commercial Viability of Organic Photovoltaics


Timothy P. Osedach*, Trisha L. Andrew,* Vladimir Bulovic
Energy Environ. Sci. 2013, 6, 711-718. PDF



Nanopatterning of Diarylethene Films via Selective Dissolution of One Photoisomer


Precious Cantu, Trisha L. Andrew* Rajesh Menon*
Appl. Phys. Lett. 2013, 103, 173112. PDF



Optical Patterning of Features with Spacing Below the Far-Field Diffraction Limit Using Absorbance Modulation


Farhana Masid, Trisha L. Andrew* Rajesh Menon*
Optics Express 2013, 21, 5209-5214. PDF



Cyclobutadiene-C60 Adducts:  N-type Materials for Organic Photovoltaic Cells with High VOC


Grace Han, William Collins, Trisha L. Andrew, Vladimir Bulovic, Timothy. M. Swager*
Adv. Funct. Mater., 2013, 23, 3061-3069. PDF


Light-Recycling Within Electronic Displays Using Deep Red and Near Infrared Photoluminescent Polarizers


Menendez-Velazquez, A.; Mulder, C. L.; Thompson, N. J.; Reusswig, P. D.; Andrew, T. L.; Rotschild, C.; Baldo, M. A.
Energy Environ. Sci. 2013, 6, 72-75. PDF


Postdoctoral and Graduate Research Publications

Andrew, T. L.; Lobez, J. M. L.; Bulovic, V.; Swager, T. M. “Improving the Performance of P3HT-Fullerene Solar Cells with Side-Chain-Functionalized Poly(thiophene) Additives:  A New Paradigm for Polymer Design” ACS Nano, 2012, 6, 3044-3056. example graphic

Paydavosi, S.; Yaul, F.; Wang, A. I.; Andrew, T. L.; Bulovic, V.; Lang, J. H. “MEMS Switches Employing Active Metal-Polymer Nanocomposites” IEEE 25th International Conference on MEMS 2012, 180-183.
Andrew, T. L.; Bulovic, V. “Bulk Heterojunction Solar Cells Containing 6,6-Dicyanofulvenes as n-Type Additives” ACS Nano, 2012, 6, 4671-4677. example graphic


Takeda, Y.; Andrew, T. L.; Lobez, J. M.; Mork, A. J.; Swager, T. M. “An Air-Stable Low-Bandgap n-Type Polymer Semiconductor Exhibiting Selective Solubility in Perfluorinated Solvents” Angew. Chem. Int. Ed., 2012, 51, 9042-9046. PDF pub15


Osedach, T. P.; Iacchetti, A.; Lunt, R. R.; Andrew, T. L.; Bulovic, V. “Near-infrared photodetector consisting of J-aggregating cyanine dye and metal oxide thin films” Appl. Phys. Lett. 2012, 101, 113303.

Osedach, T. P.; Zhao, N.; Andrew, T. L.; Bawendi, M. G.; Bulovic, V. “Bias-Stress Effect in 1,2-Ethanedithiol-Treated PbS Quantum Dot Field-Effect Transistors” ACS Nano, 2012, 6, 3121-3127.

Cantu, P.; Brimhall, N.; Andrew, T. L.; Menon, R. Subwavelength nanopatterning of photochromic diarylethene films. Appl. Phys. Lett. 2012, 100, 183103.



Brimhall, N.; Andrew, T. L.; Manthena, R. V.; Menon, R. Breaking the Far-Field Diffraction Limit in Optical Nanopatterning via Repeated Photochemical and Electrochemical Transistions in Photochromic Molecules. Phys. Rev. Lett. 2011, 107, 205501. PDF

Read the ARS Technica about this paper.

pub14

Rotschild, C.; Tomes, M.; Mendoza, H.; Andrew, T. L.; Swager, T. M.; Carmon, T.; Baldo, M. A. Cascaded Energy Transfer for Efficient Broad-Band Pumping of High-Quality Micro-Lasers Adv. Mater. 2011, 23, 3057-3060. PDF

Andrew, T. L.; Swager, T. M. Selective Detection of High Explosives Via Photolytic Cleavage of Nitroesters and Nitramines.
J. Org. Chem. 2011, 76, 2976-2993. PDF


example graphic


Andrew, T. L.; Swager, T. M. Thermally-polymerized rylene nanoparticles.
Macromolecules, 2011, 44, 2276-2281. PDF


example graphic
Andrew, T. L.; Swager, T. M. Structure Property Relationships for Exciton Transfer in Conjugated Polymers.
J. Polym. Sci. B, 2011, 49, 476-498. PDF


example graphic
Andrew, T. L.; VanVeller, B.; Swager, T. M. The Synthesis of Azaperylene-9,10-dicarboximides.
Synlett, 2010, 3045-3048. PDF


example graphic
Andrew, T. L.; Cox, J. R.; Swager, T. M. Synthesis, Reactivity, and Electronic Properties of 6,6-Dicyanofulvenes.
Org. Lett. 2010, 12, 5302-5305. PDF


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Levine, M.; Song, I.; Andrew, T. L.; Kooi, S. E.; Swager, T. M. Photoluminescent energy transfer from poly(phenyleneethynylene)s to near-infrared emitting fluorophores.
J. Polym. Sci. A, 2010, 48, 3382-3391. PDF



example graphic

Andrew, T. L.; Tsai, H.-Y.; Menon, R. Confining Light to Deep Subwavelength Dimensions to Enable Optical Nanopatterning.
Science, 2009, 324, 917-921. PDF

Read the MIT EECS Research Highlight about this paper.




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Moslin, R. M.; Andrew, T. L.; Kooi, S. E.; Swager, T. M. Anionic Oxidative Polymerization: The Synthesis of Poly(phenylenedicyanovinylene) (PPCN2V).
J. Am. Chem. Soc. 2009, 131, 20-21. PDF




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Andrew, T. L. and Swager, T. M. A Fluorescence Turn-On Mechanism to Detect the High Explosives RDX and PETN.
J. Am. Chem. Soc. 2007, 129, 7254-7255. PDF

Read the Technology Review coverage of this work.





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Andrew, T. L. and Swager, T. M. Reduced Photobleaching of Conjugated Polymer Films Through Small Molecule Additives.
Macromolecules, 2008, 41, 8306-8308. PDF



Patents

Andrew, T. L.; Fairbanks, M. Conductive Textiles.

Andrew, T. L.; Zhang, L. Polymeric Capacitors for Energy Storage Devices.

Bulovic, V.; Lang, J. H.; Lee, H. S.; Swager, T. M.; Andrew, T. L. D'Asaro, M. E.; Deotare, P.; Murarka, A.; Niroui, F.; Sletten, E.; Wang, A. I-J. Electromechanical device with reduced energy loss and flucuation due to temperature change.

Swager, T.M.; Bulovic, V.; Han, G.D.; Andrew, T. L. Functionalized nanostructures and related devices.

Swager, T.M.; Andrew, T. L. Detection of analytes using nitro-containing analytes.

Swager, T. M.; Andrew, T. L.; Thomas, S. W. III; Bouffard, J. Determination of Explosives Including RDX.

Swager, T. M.; Andrew, T. L. Stabilizing Agents for Prevention of Photobleaching.

Swager, T. M.; Andrew, T. L. Determination of Explosives via Photolytic Cleavage of Nitramines and Nitroesters.

Swager, T. M.; Lobez, J. M.; Wang, F.; Andrew, T. L.; Bulovic, V. Side-Chain Functionalized Polymer Surfactants to Decrease Charge Recombination in Solar Cells.

Swager, T. M.; Andrew, T. L. ; Bulovic, V. 6,6-Dicyanofulvenes as Fullerene Substitutes in Bulk Heterojunction Soalr Cells.

Paydavosi, S.; Wang, A. I.; Niroui, F.; Yaul, F.; Murarka, A. Andrew, T. L.; Bulovic, V.; Lang, J. Electronically Controlled Squishable Composite Switch.

Swager, T. M.; Han, G.; Collins, W.; Andrew, T. L.; Bulovic, V.;Cyclobutadiene-C60 adducts as N-type materials for photovoltaic devices.

Get in touch

Wearable Electronics Lab:
604 Lederle GRT
710 N. Pleasant St.
Amherst MA 01003
(413) 545-2755

Professor Andrew:
602 Lederle GRT
710 N. Pleasant St.
Amherst MA 01003
(413) 545-1651
tandrew[at]umass.edu