Welcome to the home page of the Paul Braun Research Group at the University of Illinois at Urbana-Champaign. Our group members perform research in the fields of materials chemistry, polymers, biomaterials, organic and inorganic self-assembly, electronic materials and photonics.

Paul V Braun – Google Scholar

New 3D microbatteries stand up to industry standard thin-film counterparts

The thin-film lithium-ion batteries used in microdevices such as portable and medical electronics may supply a good amount of power relative to their mass, but do not provide enough power for many devices due to their limited size. Researchers have introduced a fabrication process that builds microbatteries with thick, 3D electrodes using lithography and electrodeposition – and seals each unit in a gel electrolyte-filled package. The new prototype shows the highest peak power density of any reported microbatteries, the researchers said.

The new study, led by University of Illinois Urbana-Champaign postdoctoral researcher Pengcheng Sun and materials science and engineering professor Paul Braun, is published in the journal Advanced Materials.

Read the full story: https://news.illinois.edu/view/6367/1737488480

Read the full paper:  “High-performance packaged 3D lithium-ion microbatteries fabricated using imprint lithography

Researchers confront optics and data-transfer challenges with 3D-printed lens

Researchers have developed new 3D-printed microlenses with adjustable refractive indices – a property that gives them highly specialized light-focusing abilities. This advancement is poised to improve imaging, computing and communications by significantly increasing the data-routing capability of computer chips and other optical systems, the researchers said.

The study was led by University of Illinois Urbana-Champaign researchers Paul Braun and Lynford Goddard and is the first to demonstrate the ability to adjust the direction in which light bends and travels through a lens with sub-micrometer precision.

Read the full story: Researchers confront optics and data-transfer challenges with 3D-printed lens
The results of the study are published in the journal Light: Science and Application: DOI: 10.1038/s41377-020-00431-3

Braun Group Recent Publications
J.G. Kang, H. Jang, J. Ma, Q. Yang, K. Hattar, Z. Diao, R.L. Yuan, J.M. Zuo, S. Sinha, D. Cahill, P. Braun, Ultralow thermal conductivity in nanoporous crystalline Fe3O4, Journal of Physical Chemistry C, 125, 12, 6897-6908 (2021). DOI 10.1021/acs.jpcc.1c00411
Kollarigowda and P.V. Braun, Direct and Divergent Solid-Phase Synthesis of Azobenzene and Spiropyran Derivatives, Journal of Organic Chemistry, 86, 6, 4391-4397 (2021). DOI: 10.1021/acs.joc.0c02375
S. Zeraati, S. Mirkhani, P. Sun, M. Naguib, P.V. Braun and U. Sundararaj, Improved Synthesis of Ti3C2Tx MXene Resulting in Exceptional Electrical Conductivity, High Synthesis Yield, and Enhanced Capacitance, Nanoscale, 13, 3572-3580 (2021). DOI: 10.1039/D0NR06671K
T. Yang, P.V. Braun, N. Miljkovic and W.P. King, Phase Change Material Heat Sink for Transient Cooling of High-Power Devices, Journal of Heat and Mass TransferPhase Change Material Heat Sink for Transient Cooling of High-Power Devices, Journal of Heat and Mass Transfer, 170, 121033 (2021). DOI: 10.1016/j.ijheatmasstransfer.2021.121033
Zheng, B. Chen, Y. Xu, N. Fritz, Y. Gurumukhi, J. Cook, M.N. Ates, N. Miljkovic and P.V. Braun, A Gaussian Process-Based Crack Pattern Modeling Approach for Battery Anode Materials Design, Journal of Electrochemical Energy Conversion and Storage, 18, 1, 011011 (2021). DOI: 10.1115/1.4046938
P. Sun, X. Li, J. Shao and P.V. Braun, High‐Performance Packaged 3D Lithium‐Ion Microbatteries Fabricated Using Imprint Lithography, Advanced Materials, 33, 1, 2006229 (2021). DOI: 10.1002/adma.202006229
C.R. Ocier, C.A. Richards, D.A. Bacon-Brown, Q. Ding, R. Kumar, T.J. Garcia, J. van de Groep, J.-H. Song, A.J. Cyphersmith, A. Rhode, A.N. Perry, A.J. Littlefield, J. Zhu, D. Xie, H. Gao, J.F. Messinger, M.L. Brongersma, K.C. Toussaint Jr., L.L. Goddard and P.V. Braun, Direct laser writing of volumetric gradient index lenses and waveguides, Light Science & Applications 9, 196 (2020). DOI: 10.1038/s41377-020-00431-3
S. Kim, B. Lee, J.T. Reeder, S.H. Seo, S.U. Lee, A. Hourlier-Fargette, J. Shin, Y. Sekine, H. Jeong, Y.S. Oh, A.J. Aranyosi, S.P. Lee, J.B. Model, G. Lee, M.H. Seo, S.S. Kwak, S. Jo, G. Park, S. Han, I. Park, H.I. Jung, R. Ghaffari, J. Koo, P.V. Braun, and J.A. Rogers, Soft, skin-interfaced microfluidic systems with integrated immunoassays, fluorometric sensors and impedance measurement capabilities, PNAS, 117, 27906-27915 (2020). DOI: 10.1073/pnas.2012700117