Properties of Nitrogen-Doped Nano-Crystalline Graphite Thin Films and Their Application as Electrochemical Sensors

• Published in: Journal of the Electrochemical Society 2020-01, Vol.167 (12), p.126510
• Main Authors: Simionescu, Octavian-Gabriel, Romanitan, Cosmin, Albu, Camelia, Pachiu, Cristina, Vasile, Eugeniu, Djourelov, Nikolay, Tutunaru, Oana, Stoian, Marius Constantin, Kusko, Mihaela, Radoi, Antonio
• Format: Article
• Language: English
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1945-7111/abb1d4

Herein, several nitrogen-doped nano-crystalline graphite films (N-NCG) were prepared via plasma-enhanced chemical vapor deposition (PECVD); nano-crystalline graphite (NCG) was doped by adding ammonia gas during the PECVD growth. To develop electrochemical probes that can compete with glassy carbon (GC) electrodes for anthracene sensing, the N-NCG electrodes were systematically investigated using different techniques, including atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis, Raman spectroscopy, cyclic voltammetry (CV), and differential pulsed voltammetry (DPV). The obtained sensors were tested against anthracene in an acetonitrile/water mixture (80/20 v/v) wherein the N-NCG 3 and N-NCG 5 electrochemical probes showed analytical features comparable with those of the GC electrode. The best competitor for GC was N-NCG 3 in terms of linear working range (2.5 M-1 mM) and sensitivity (y = 6.09 × 10−6 + 1.21 x, r2 = 0.9997 and y = 1.23 × 10−5 + 0.84 x, r2 = 0.9959 for GC and N-NCG 3, respectively).