Contributed Speaker
Dr. Bizan N. Balzer
Triboelectric Energy Harvesting: Contact Electrification via Redox Active Donor-Acceptor Pairs
Nisha Ranjan 1,2 , Philipp Gaiser 3 , Zohreh Izadi 2 , Andrej Weber 4 , Rekha Sharma 2,3 , Leonhard Mayrhofer 6 , Michael Moseler 2,5,6 , Michael Walter 2,6,* , Birgit Esser 2,4* and
Bizan N. Balzer 1,2,5,*
1 Institute of Physical Chemistry, University of Freiburg, Albertstr. 21, 79104 - Freiburg, Germany
2 Cluster of Excellence liv MatS @ FIT – Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Georges-Köhler-Allee 105, 79110-Freiburg, Germany
3 Institute of Organic Chemistry, University of Freiburg, Albertstr. 21, 79104 - Freiburg, Germany
4 Institute of Organic Chemistry II and Advanced Materials, Ulm University, Albert-Einstein-Allee 11, 89081-Ulm, Germany
5 Freiburg Materials Research Center (FMF), University of Freiburg, Stefan-Meier-Str. 21, 79104 - Freiburg, Germany
6 Fraunhofer IWM, Wöhlerstrasse 11, 79108-Freiburg, Germany
Website: https://www.balzer-lab.com
Energy harvesting using renewable energy sources is a major issue for fighting today's energy crisis. A well-known but not yet fully understood effect, the triboelectricity, can serve to provide future triboelectric nanogenerators (TENGs) [1]. One mode of triboelectric energy harvesting is contact electrification, wherein objects are charged by a contact-separation process. Until now, a comprehensive general explanation of this phenomenon and the search for efficient contact electrification materials has been challenging [2, 3]. Here, we present an atomic force microscopy (AFM)-based assay for contact electrification at the microscale (CEAM) based on a combination of AFM-based force spectroscopy and Kelvin probe force microscopy (KPFM). Furthermore, redox-active molecules with a low ionization potential (donor) and high electron affinity (acceptor) are functionalized to micro-patterned Au surfaces and Au coated AFM cantilever tips, respectively. We use a combination of AFM-based force spectroscopy and Kelvin probe force microscopy (KPFM) as a proof of principle of a considerable surface potential change upon the contact-separation process of the functionalized tip-substrate pairs. Our results are crucial for the development of materials and design principles for future TENGs suitable for energy efficient materials systems.
References
[1] F.-R. Fan, Z.-Q. Tian, ZL Wang, Flexible triboelectric generator , Nano Energy , 1(2), 2012, 328-334, https://doi.org/10.1016/j.nanoen.2012.01.004.
[2] DJ Lacks, T. Shinbrot, Long-standing and unresolved issues in triboelectric charging , Nature Review Chemistry, 3, 2019, 465-476, https://doi.org/10.1038/s41570-019-0115-1.
[3] DJ Lacks, and RM Sankaran, Contact electrification of insulating materials , Journal of Physics D: Applied Physics , 44, 2011, 453001, https://doi.org/10.1088/0022-3727/44/45/453001.