دورية أكاديمية

Monolayer graphene/SiC Schottky barrier diodes with improved barrier height uniformity as a sensing platform for the detection of heavy metals

التفاصيل البيبلوغرافية
العنوان: Monolayer graphene/SiC Schottky barrier diodes with improved barrier height uniformity as a sensing platform for the detection of heavy metals
المؤلفون: Ivan Shtepliuk, Jens Eriksson, Volodymyr Khranovskyy, Tihomir Iakimov, Anita Lloyd Spetz, Rositsa Yakimova
المصدر: Beilstein Journal of Nanotechnology, Vol 7, Iss 1, Pp 1800-1814 (2016)
بيانات النشر: Beilstein-Institut, 2016.
سنة النشر: 2016
المجموعة: LCC:Technology
LCC:Chemical technology
LCC:Science
LCC:Physics
مصطلحات موضوعية: barrier height, graphene, heavy metals, Schottky diode, sensing platform, SiC, Technology, Chemical technology, TP1-1185, Science, Physics, QC1-999
الوصف: A vertical diode structure comprising homogeneous monolayer epitaxial graphene on silicon carbide is fabricated by thermal decomposition of a Si-face 4H-SiC wafer in argon atmosphere. Current–voltage characteristics of the graphene/SiC Schottky junction were analyzed by applying the thermionic-emission theory. Extracted values of the Schottky barrier height and the ideality factor are found to be 0.4879 ± 0.013 eV and 1.01803 ± 0.0049, respectively. Deviations of these parameters from average values are smaller than those of previously observed literature data, thereby implying uniformity of the Schottky barrier height over the whole diode area, a stable rectifying behaviour and a good quality of ohmic palladium–graphene contacts. Keeping in mind the strong sensitivity of graphene to analytes we propose the possibility to use the graphene/SiC Schottky diode as a sensing platform for the recognition of toxic heavy metals. Using density functional theory (DFT) calculations we gain insight into the nature of the interaction of cadmium, mercury and lead with graphene as well as estimate the work function and the Schottky barrier height of the graphene/SiC structure before and after applying heavy metals to the sensing material. A shift of the I–V characteristics of the graphene/SiC-based sensor has been proposed as an indicator of presence of the heavy metals. Since the calculations suggested the strongest charge transfer between Pb and graphene, the proposed sensing platform was characterized by good selectivity towards lead atoms and slight interferences from cadmium and mercury. The dependence of the sensitivity parameters on the concentration of Cd, Hg and Pb is studied and discussed.
نوع الوثيقة: article
وصف الملف: electronic resource
اللغة: English
تدمد: 2190-4286
Relation: https://doaj.org/toc/2190-4286
DOI: 10.3762/bjnano.7.173
URL الوصول: https://doaj.org/article/f2c25e2d7d094f46958fda00e9a3e89e
رقم الأكسشن: edsdoj.f2c25e2d7d094f46958fda00e9a3e89e
قاعدة البيانات: Directory of Open Access Journals
الوصف
تدمد:21904286
DOI:10.3762/bjnano.7.173