Electrochemical Reaction in Hydrogen Peroxide and Structural Change of Platinum Nanoparticle-Supported Carbon Nanowalls Grown Using Plasma-Enhanced Chemical Vapor Deposition

Abstract

Hydrogen peroxide (H 2 O 2 ) reactions on platinum nanoparticle-decorated carbon nanowalls (Pt-CNWs) under potential applications were investigated on a platform of CNWs grown on carbon fiber paper (CFP) using plasma-enhanced chemical vapor deposition. Through repeated cyclic voltammetry (CV), measurements of 1000 cycles using the Pt-CNW electrodes in phosphate-buffered saline (PBS) solution with 240 µM of H 2 O 2 , the observed response peak currents of H 2 O 2 reduction decreased with the number of cycles, which is attributed to decomposition of H 2 O 2 . After CV measurements for a total of 3000 cycles, the density and height of CNWs were reduced and their surface morphology changed. Energy-dispersive X-ray (EDX) compositional mapping revealed agglomeration of Pt nanoparticles around the top edges of CNWs. The degradation mechanism of Pt-CNWs under potential application with H 2 O 2 is discussed by focusing on the behavior of OH radicals generated by the H 2 O 2 reduction.

On the Structural, Morphological, and Electrical Properties of Carbon Nanowalls Obtained by Plasma-Enhanced Chemical Vapor Deposition

“…The positive value of R H indicated that the fabricated samples have p-type electrical conduction, at room temperature. Even though the values are slightly smaller, these results are similar to others from literature; the buffer layer was changed as indium tin oxide [39] or titanium nitride [9].…”

“…Journal of Nanomaterials despite this, the formation of clusters is reduced and a lot of individual edges can be still observed. This property is an intrinsic one, and it is related to the self-support feature of such architectures [9]. As expected, the large value of the height of CNWs is strongly correlated with the working time [7].…”

“…Except for the 2D-band which is slightly shifted to the infrared region of the electromagnetic spectrum, all the other peaks have typical values for CNWs. The D-band, located at 1350 cm -1 , is the signature of the inelastic scattering of transverse optical phonons on the structural point-like defects, and the G-band at 1580 cm -1 is specific to the ring structure of graphite [9], indicating the presence of C-C bonds [31].…”

“…Like the case of other allotropes of carbon, the versatility of CNWs for various applications was proved by the customization of their physical and chemical properties, e.g., the morphology of samples can be easily controlled by the concentration of carbon atoms [7], and the surface can be tuned to be hydrophilic or hydrophobic by chemical and thermal treatments performed during the growth process [8]. Due to their unique configuration of graphene-like layers vertically aligned on the substrate [9] and of the presence of curly sharp edges, CNWs have a high aspect ratio as around 100 and a large surface area of about 1000 m 2 /g [4,10]. Also, because the graphene layers are interconnected, the CNWs are characterized by good electrical and thermal conductivity [11].…”

Biocompatibility of conformal silicon carbide on carbon nanowall scaffolds

“…CNWs were deposited on silicon (Si) substrates using radical injection-plasma enhanced chemical vaper deposition (RI-PECVD) equipment. 10,11,15,16,[26][27][28][29] The substrates used a low-resistivity (⩽0.1 Ω cm) n-type Si (100) wafer. The equipment used a tandem structure with a surface wave plasma (SWP) and a very high frequency (VHF) capacitively coupled plasma (CCP) source connected by a showerhead type CCP electrode.…”