scholarly journals Electroanalytical Performance of Nitrogen-Doped Graphene Films Processed in One Step by Pulsed Laser Deposition Directly Coupled with Thermal Annealing

Materials ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 666 ◽  
Author(s):  
Florent Bourquard ◽  
Yannick Bleu ◽  
Anne-Sophie Loir ◽  
Borja Caja-Munoz ◽  
José Avila ◽  
...  

Graphene-based materials are widely studied to enable significant improvements in electroanalytical devices requiring new generations of robust, sensitive and low-cost electrodes. In this paper, we present a direct one-step route to synthetize a functional nitrogen-doped graphene film onto a Ni-covered silicon electrode substrate heated at high temperature, by pulsed laser deposition of carbon in the presence of a surrounding nitrogen atmosphere, with no post-deposition transfer of the film. With the ferrocene methanol system, the functionalized electrode exhibits excellent reversibility, close to the theoretical value of 59 mV, and very high sensitivity to hydrogen peroxide oxidation. Our electroanalytical results were correlated with the composition and nanoarchitecture of the N-doped graphene film containing 1.75 at % of nitrogen and identified as a few-layer defected and textured graphene film containing a balanced mixture of graphitic-N and pyrrolic-N chemical functions. The absence of nitrogen dopant in the graphene film considerably degraded some electroanalytical performances. Heat treatment extended beyond the high temperature graphene synthesis did not significantly improve any of the performances. This work contributes to a better understanding of the electrochemical mechanisms of doped graphene-based electrodes obtained by a direct and controlled synthesis process.

2010 ◽  
Vol 25 (4) ◽  
pp. 680-686 ◽  
Author(s):  
Zhifeng Ying ◽  
Wentao Tang ◽  
Zhigao Hu ◽  
Wenwu Li ◽  
Jian Sun ◽  
...  

The structure and properties of HfO2 films deposited by plasma assisted reactive pulsed laser deposition and annealed in N2 were studied upon thermal annealing as well as the evaluation of thermal stability by Fourier transform infrared spectroscopy, spectroscopic ellipsometry, and optical transmission measurements. The as-deposited HfO2 films appear predominantly monoclinic with an amorphous matrix which becomes crystallized after high-temperature annealing. No interfacial SiOx is observed for the as-deposited films on Si. The deposited HfO2 films exhibit good thermal stability and show excellent transparency in a wide spectral range with optical band gap energies of 5.65–5.73 eV depending on annealing temperature. An improvement in the optical properties by high-temperature annealing is also observed.


2007 ◽  
Vol 89 (4) ◽  
pp. 933-940 ◽  
Author(s):  
I. Marozau ◽  
M. Döbeli ◽  
T. Lippert ◽  
D. Logvinovich ◽  
M. Mallepell ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document