Compositional and Electrochemical Characterization of Noble Metal−Diamondlike Carbon Nanocomposite Thin Films

Abstract

A detailed characterization of platinum- and gold-diamondlike carbon (DLC) nanocomposite films deposited onto silicon substrates is presented. A modified pulsed laser deposition (PLD) technique was used to incorporate noble metal nanoclusters into hydrogen-free DLC films. Several analytical techniques, including transmission electron microscopy, atomic force microscopy, Rutherford backscattering spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and nanoindentation testing, were used to investigate these thin films in an effort to determine their physical and electrochemical properties. Rutherford backscattering spectroscopy indicated that the gold- and platinum-DLC films contain metal concentrations between three and 36 atomic percent. Cross-sectional transmission electron microscopy revealed that metal is present as arrays of noble metal islands embedded within the DLC matrix, while atomic force microscopy provided evidence of target splashing. In addition, due to the inclusion of metal, metal-DLC thin films exhibited greater conductivity than their metal-free counterparts. The electrochemical properties were studied using quasi-reversible redox couples and correlated to the metal concentration. Finally, the influence of the layer's composition on the electron-transfer kinetics and the achievable working potential window is discussed. The results discussed herein suggest that metal-DLC thin films grown by pulsed laser deposition present a promising alternative electrode material for electrochemistry.

Electrochemical detection of hydrogen peroxide on platinum-containing tetrahedral amorphous carbon sensors and evaluation of their biofouling properties

“…Thus, it is suggested that addition of Pt induces formation of higher amount of sp 2 fraction and higher conductivity for ta-C. Menegzzo et al [26] have previously reported similar results for Pt containing DLC. Moreover, it was show here that adding Pt in ta-C does not significantly change conduction mechanism from SCL currents theory significantly.…”

“…For ta-C/Pt it is suggested that the anodic peak at -0.48 V and cathodic peak at -0.46 V (inset in Figure 4) are also related to hydrogen adsorption and desorption, respectively, and indicate the presence of Pt in the material. Menegazzo et al [26] inspected the electrochemical properties of Pt-DLC and Au-DLC films. They concluded that even though the working range for the composite is narrower compared to the carbon support alone it is still larger than for pure metal offering also chemical and mechanical stability of an inert ceramic.…”

“…However, it has been shown that doping DLC with Pt affect its electrochemical properties [26]- [28]. Pleskov et al [28] suggested that Pt acts as a catalyst for charge transfer in otherwise electrochemically inactive DLC.…”

Local reactivity of diamond-like carbon modified PTFE membranes used in SO2 sensors

“…Cyclic voltammetry studies have revealed an almost ideal reversible behavior of redox species such as [Ru(NH 3 ) 6 ] 3+/2+ and [Fe(CN) 6 ] 3−/4− for both doped and undoped DLC coatings on different types of silicon wafers. Moreover, these studies suggested that DLC electrodes are similar to diamond electrodes with respect to the rather wide potential window in aqueous solutions, the good signal-to-noise ratio and the high stability [8,9,20]. Polycarbonate and dialysis membranes coated with DLC films were successfully used as antifouling membrane in enzyme based biosensors [21][22][23].…”

Non-enzymatic hydrogen peroxide detection using gold nanoclusters-modified phosphorus incorporated tetrahedral amorphous carbon electrodes

“…These conductive carbon films possess low double layer capacitance, a large potential window, low background current, stability in challenging environments, comparative electrocatalysis and high resistance to product adsorption and do not require a non-activation treatment of the electrode surface by polishing, heating or laser activation. With ambient temperature growth on virtually any substrate and smooth surfaces, doped ta-C or DLC films exhibit many advantages over the difficult-to-nucleate, high-temperature growth boron-doped diamond (BDD) films and "classical" carbon materials and are regarded as an appropriate material for electroanalytical applications [5,8,[12][13][14][15][16][17][18][19][20].…”