Abstract
Materials keeping thickness in atomic scale but extending primarily in lateral dimensions offer properties attractive for many emerging applications. However, compared to crystalline counterparts, synthesis of atomically thin films in the highly disordered amorphous form, which avoids nonuniformity and defects associated with grain boundaries, is challenging due to their metastable nature. Here we present a scalable and solution-based strategy to prepare large-area, freestanding quasi-2D amorphous carbon nanomembranes with predominant sp2 bonding and thickness down to 1–2 atomic layers, from coal-derived carbon dots as precursors. These atomically thin amorphous carbon films are mechanically strong with modulus of 400 ± 100 GPa and demonstrate robust dielectric properties with high dielectric strength above 20 MV cm−1 and low leakage current density below 10−4 A cm−2 through a scaled thickness of three-atomic layers. They can be implemented as solution-deposited ultrathin gate dielectrics in transistors or ion-transport media in memristors, enabling exceptional device performance and spatiotemporal uniformity.
| Original language | English |
|---|---|
| Article number | 93 |
| Journal | Communications Engineering |
| Volume | 2 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 2023 |
Funding
This project was funded by the U.S. Department of Energy (DOE), National Energy Technology Laboratory, in part, through a site support contract and U.S. National Science Foundation grant DMR 2139185, DMR 1828671, and ECCS 1950182. Neither the United States Government nor any agency thereof, nor any of their employees, nor the support contractor, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the U.S. Government or any agency thereof. The views and opinions of the authors expressed herein do not necessarily state or reflect those of the U.S. Government or any agency thereof. F.A. acknowledges the support of the PPG-MRL Graduate Research Assistantship program. B.R. acknowledges support from the Sandia National Laboratory\u2019s LDRD program via the Sandia-UIUC collaboration, project number 218456. Activities at the Oak Ridge National Laboratory, UT-Battelle, LLC, were carried out under contract no. DE-AC05-00OR22725 with the DOE and sponsored by the Office of Fossil Energy and Carbon Management, Advanced Coal Processing Program, Consortium on Coal-based Carbon Materials Manufacturing. STEM imaging (A.B.) was conducted as a part of a user project at the Center for Nanophase Materials Sciences (CNMS), which is a DOE, Office of Science User Facility at Oak Ridge National Laboratory. A.S. acknowledges support from the Office of Naval Research (Grant no. N00014-18-1-2605). This work made use of the Illinois Campus Cluster, a computing resource that is operated by the Illinois Campus Cluster Program (ICCP) in conjunction with the National Center for Supercomputing Applications (NCSA) and which is supported by funds from the University of Illinois at Urbana-Champaign. We thank Dr. Richard A. Wolfe from Carbon Technology Co. (Bristol, VA) for supplying the coal char used for the synthesis of carbon dots, Dr. Richard T. Haasch for assistance with XPS measurements, and Dr. Thuy Duong Nguyen Phan for help with XPS data analysis.