Abstract

The phenol quantification using boron-doped nanocrystalline diamond (BDND) from electroanalytical technique of square wave voltammetry (SWV) is reported. BDND depositions were performed using Hot Filament Chemical Vapor Deposition reactor, where it was possible to grow films with statics substrate-holder (sample S1) or with spinning substrate-holder (sample S2). The variation of this growth parameter induced significant changes on the electrode properties. For example, the electrode S2 presented smoothness surface with low roughness in relation to that for electrode S1. Besides, Raman spectra showed different features for both electrodes that could be related to boron incorporation. Electrochemical measurements also presented differences between electrodes, showing the advantages of electrode S2, such as, rapid charge transfer, large electrochemical area and excellent phenol detection limit 0.1 mg L−1. The phenol standard sample of 8.0 mg L−1 was used to validate the application of this electrode as a nanosensor. Its concentration calculated from SWV using electrode S2 was 8.2 ± 0.2 mg L−1 while from Ion Chromatograph it was 7.9 ± 0.1 mg L−1. These results demonstrated the high potential of BDND electrodes for electroanalytical applications.

Highlights

The variation of a deposition parameter influenced on the diamond films growth. We analyze two types of boron-doped diamond electrodes (BDND). The electrode grown with spinning substrate-holder presented good electrochemical properties. This electrode reached a good phenol detection limit of around 0.1 mg L−1. Our results were validated with the Ion Chromatography assay, showing the availability of BDND electrode as a nanosensor.

Keywords: Nanocrystalline; Doped diamond films; Phenol oxidation; Electroanalysis; Detection; Chromatography