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Title Development of “Direct-current Electricity Harvesting Technology” for the First Time in the World
Writer sogpr Date 2018-01-08 Views 727

Prof. Lee Jung-chul Developed the Direct-current Electricity Harvesting Technology

Using Stratification Transition-metal Compound MoS2

And Probe of Conducting Atomic Force Microscopy

- Development and Effect Verification of Energy Harvest Collecting Technology

that Does Not Require Rectification -


A research team led by Prof. Lee Jung-chul developed a world-first technology for direct-current electricity harvesting using stratification transition-metal compound MoS2 and probe of conducting atomic force microscopy through research jointly conducted with Prof. Thomas Thundat from the Department of Chemicals and Materials Engineering at the University of Alberta and Prof. Zhiyu Hu of the Department of Micro/Nano Electronics at Shanghai Jiao Tong University. Thanks to this technology, the limitations of existing triboelectricity nanogenerators (TENG) based on polymers have been overcome. The results of the research were posted online on December 11 in Nature Nanotechnology: IF – 38.986, an affiliated magazine of Nature.



<(Left) Prof. Lee Jung-chul, (right) Kim Seok Beom>


□ Paper and Author

- Paper: Direct-current triboelectricity generation by a sliding Schottky nanocontact on MoS2 multilayers

- Author: Jun Liu (Lead Author, Univ. of Alberta), Ankur Goswami, Keren Jiang, Faheem Khan, Ryan McGee, Zhi Li (Co-author, Univ. of Alberta), Prof. Zhiyu Hu (Co-author, Shanghai Jiao Tong Univ.), Kim Seok Beom (Co-author, Sogang Univ.), Prof. Lee Jung-chul (Co-author, Sogang Univ.), Prof. Thomas Thundat (Corresponding Author, Univ. of Alberta)

- Posted online on Nature Nanotechnology, December 11, 2017, edition


Direct diversion from mechanical energy to electrical energy through a Nano-based device is said to have endless potential in application for energy harvesting. To this point, existing triboelectric nanogenerators (TENG) have been able to generate only AC frictional electricity and, therefore, the process of rectification that transforms AC to DC (direct current) has been required in order for the nanogenerator to be utilized. In addition, the current density was limited. The joint research team of Sogang University-University of Alberta-Shanghai Jiao Tong University made the Schottky Nano-scale sliding contact on the surface of Molybdenum-disulfide (MoS2) that went through pulsed laser deposition by using the probe of conducting atomic force microscopy and implemented harvesting of continuous current with a high-current density of 106 A/m2. At the same time, conducting finite element analysis (conducting a strong electric field around the Nano-scale probe to enhance the non-equilibrium charge carrier transport) was found to generate the abnormally high-current density that was observed. The team set up the hypothesis that electrical excitation from friction induces current transmission and, by analyzing the Nano-scale current-voltage spectrum, it was found that the Schottky screen on probe-MoS2 contact plays an important role in effective direct-current electricity harvesting.


Prof. Lee Jung-chul said, “The raised concept is believed to generate direct current frictional electricity in high-current density when the micro-processed electrode array or the contact surface is expanded in connection with the efficiently modified electrode.” He also added, “This is expected to be utilized in R&D for next-generation energy harvesting.”



(a) Performance Property of the Existing Triboelectricity Nanogenerators (TENG)

(b) Mimetic Diagram of the Direct-current Electricity Harvesting Using the Conductive Probe and MoS2 from Pulsed Laser Deposition

(c)-(f) Topography Image of Scanning Probe Microscopy and Generated Result of Current Image

(g) Scanning Result of Current Data Line on the White Dotted Line of (f)