The performance of devices and systems based on two-dimensional material systems depends critically on the quality of the contacts between 2D material and metal. A low contact resistance is an imperative requirement to consider graphene as a candidate material for electronic and optoelectronic devices. Unfortunately, measurements of contact resistance in the literature do not provide a consistent picture, due to limitations of current graphene technology, and to incomplete understanding of influencing factors. Here we show that the contact resistance is intrinsically dependent on graphene sheet resistance and on the chemistry of the graphene-metal interface. We present a physical model of the contacts based on ab-initio simulations and extensive experiments carried out on a large variety of samples with different graphene-metal contacts. Our model explains the spread in experimental results as due to uncontrolled graphene doping and suggests ways to engineer contact resistance. We also predict an achievable contact resistance of 30 Ω·μm for nickel electrodes, extremely promising for applications.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5506027 | PMC |
http://dx.doi.org/10.1038/s41598-017-05069-7 | DOI Listing |
Proc Natl Acad Sci U S A
January 2025
Laboratory for Protein Crystallography, Institute for Protein Research, Osaka University, Suita, Osaka 565-0871, Japan.
[FeFe]-hydrogenases catalyze the reversible two-electron reduction of two protons to molecular hydrogen. Although these enzymes are among the most efficient H-converting biocatalysts in nature, their catalytic cofactor (termed H-cluster) is irreversibly destroyed upon contact with dioxygen. The [FeFe]-hydrogenase CbA5H from has a unique mechanism to protect the H-cluster from oxygen-induced degradation.
View Article and Find Full Text PDFACS Nano
January 2025
School of Physics and Astronomy, Monash University, Clayton, Victoria 3800, Australia.
Van der Waals electrode integration is a promising strategy to create nearly perfect interfaces between metals and 2D materials, with advantages such as eliminating Fermi-level pinning and reducing contact resistance. However, the lack of a simple, generalizable pick-and-place transfer technology has greatly hampered the wide use of this technique. We demonstrate the pick-and-place transfer of prefabricated electrodes from reusable polished hydrogenated diamond substrates without the use of any sacrificial layers due to the inherent low-energy and dangling-bond-free nature of the hydrogenated diamond surface.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan.
Semiconducting transition metal dichalcogenides (TMDs) possess exceptional photoelectronic properties, rendering them excellent channel materials for phototransistors and holding great promise for future optoelectronics. However, the attainment of high-performance photodetection has been impeded by challenges pertaining to electrical contact. To surmount this obstacle, we introduce a phototransistor architecture, in which the WS channel is connected with an alternating WS-WSe strip superstructure, strategically positioned alongside the source and drain contact regions.
View Article and Find Full Text PDFUnlabelled: The intestinal diarrheal pathogen colonizes the host terminal ileum, a microaerophilic, glucose-poor, nitrate-rich environment. In this environment, respires nitrate and increases transport and utilization of alternative carbon sources via the cAMP receptor protein (CRP), a transcription factor that is active during glucose scarcity. Here we show that nitrate respiration in aerated cultures is under control of CRP and, therefore, glucose availability.
View Article and Find Full Text PDFRSC Adv
January 2025
Institute of Resources and Environmental Engineering, Shanxi University, Shanxi Yellow River Laboratory Taiyuan China
Coal combustion generates soot-type air pollution, and NO, as a typical pollutant, is the main haze-causing pollutant. The degradation of NO by means of photocatalytic superhydrophobic multifunctional coatings is both durable and economical. The precipitation method was employed to create a p-n type BiOBr/α-FeO photocatalytic binary system.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!