The doping level of boron-doped diamond electrodes affects the voltammetric sensing ofuric acid

In this work, the electrochemical oxidation and subsequent determination of uric acid was investigated using boron-doped diamond electrodes with various B/C ratios (0-2000 ppm). The cyclic voltammetric study showed one irreversible oxidation peak at +(1.1-1.25) V (vs. Ag/AgCl/3 M KCl) in the presence of Britton-Robinson buffer (pH 2.25) depending on the boron content. Employing differential pulse voltammetry using the 2000 ppm boron-doped diamond electrode the acquired analytical parameters were as follows: a limit of detection of 7.7 M, a limit of quantification of 26 M and intra-day repeatability (relative standard deviation of 2.9% for n = 15). After performing an interference study, the method was applied to the determination of uric acid in biological samples (human urine). The uric acid concentrations determined in the urine samples were compared with the reference values stated in the literature. The proposed methodology using boron-doped diamond electrodes could find applications in uric acid sensing within clinical, pharmaceutical and environmental analysis

Supplementary data for article: Samiec, P.; Švorc, Ľ.; Stanković, D. M.; Vojs, M.; Marton, M.; Navrátilová, Z. Mercury-Free and Modification-Free Electroanalytical Approach towards Bromazepam and Alprazolam Sensing: A Facile and Efficient Assay for Their Quantification in Pharmaceuticals Using Boron-Doped Diamond Electrodes. Sensors and Actuators, B: Chemical 2017, 245, 963–971. https://doi.org/10.1016/j.snb.2017.02.023

Supplementary material for: [https://doi.org/10.1016/j.snb.2017.02.023]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2442]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3080

Pyrolyzed photoresist film electrodes for application in electroanalysis

Pyrolyzed Photoresist Film Electrodes for Application in Electroanalysis Pyrolyzed photoresist film (PPF) electrodes for application in electroanalysis were prepared on alumina substrates. These electrodes were characterized for their electrical, microstructural (by Raman spectroscopy) and electrochemical properties. As a support, the PPF electrodes were tested for simultaneous determination of Pb(II), Cd(II) and Zn(II) in an aqueous solution on in-situ formed bismuth film by square wave voltammetry (SWV). The dependence of the stripping responses on the concentration of target metals was linear in the range from 1 × 10-8 to 9 × 10-8 mol/L. The effect of activation of the PPF surface by argon plasma on analytical performance of bismuth film electrode (BiFE) on PPF support was also investigated.</jats:p

Supplementary data for article: Samiec, P.; Švorc, Ľ.; Stanković, D. M.; Vojs, M.; Marton, M.; Navrátilová, Z. Mercury-Free and Modification-Free Electroanalytical Approach towards Bromazepam and Alprazolam Sensing: A Facile and Efficient Assay for Their Quantification in Pharmaceuticals Using Boron-Doped Diamond Electrodes. Sensors and Actuators, B: Chemical 2017, 245, 963–971. https://doi.org/10.1016/j.snb.2017.02.023

Supplementary material for: [https://doi.org/10.1016/j.snb.2017.02.023]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2442]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3080

Raman spectroscopy of amorphous carbon prepared by pulsed arc discharge in various gas mixtures

To meet various application requirements, it is important to enable an improvement of a-C structure and properties, such as hardness, adhesion, and wear resistance. In this study, we used the Raman spectroscopy to investigate the a-C thin films structure dependence on the different deposition parameters. The effect of nitrogen, argon, and hydrogen gas flow rate was analyzed to determine the influence on the film properties. The change in the gas type, combination, and flow had a significant influence on the D and G bands of the a-C Raman spectra. The addition of N2 into the chamber promoted the sp2 creation, while with adding hydrogen the layer contained more sp3 bonds. The depositions of a-C thin films were carried out in pulsed arc discharge vacuum installation. Micro-Raman measurements of the deposited materials were performed using an ISA Dilor-Jobin Yvon-Spex Labram confocal system with 632.8 nm radiation from a He-Ne laser using a back-scattering geometry

Electrodeposition of cuprous oxide on boron doped diamond electrodes

Nowadays, Cu_2O is very promising electrode material for photoelectrochemical applications. In this paper, we report on the controllable synthesis of Cu_2O single particles as well as compact layers on Boron Doped Diamond (BDD) electrodes using potentiostatic deposition in continuous and pulse mode. The BDD layers were prepared with different B/C ratios in the gas phase in order to investigate boron doping level influence on the Cu_2O properties. The effect of electrodeposition conditions such as deposition regime and pulse duration was investigated as well. The Cu_2O covered BDD electrodes were analysed by Scanning Electron Microscopy (SEM) and Raman spectroscopy. Improvement in the homogeneity of the electrodeposit and removal of clusters were achieved when the pulse potentiostatic regime was used. Using the same pulse electrodeposition parameters, we confirmed the possibility of controlling the deposition rate of Cu_2O by varying the BDD conductivity. Finally, we were able to scale the size of Cu_2O particles by changing the number of deposition pulses. The obtained results have shown a great potential of controlling the morphology, amount, size and distribution of Cu_2O films on BDD substrates by changing the boron doping level and electrodeposition conditions as well. The investigations reported herein allowed us to better understand the deposition mechanism of Cu_2O on BDD electrodes which could then be used for preparation of active layers for electrochemical applications and in optoelectronic devices such as solar cells and photodetectors

Chemically Deposited Boron‐Doped Diamond Screen‐Printed Electrodes for the Detection of Manganese

Manganese (Mn2+) is widely used in industrial applications, including steel production, battery manufacturing, and fertilizers. These activities, along with natural processes, contribute to its presence in environmental water. This study investigates the electrochemical behavior of manganese using laboratory‐fabricated screen‐printed carbon electrodes (SPEs) combining diamond (D), carbon black (CB), and boron‐doped diamond (BDD) in eight different configurations: D + BDD, first layer (L1): CB + second layer (L2): D + BDD, CB + D + BDD, or CB pure, each of them with a chlorinated or plain pseudo‐reference. The screen‐printed electrodes were characterized physicochemically and electrochemically, with their electroactive areas and electron transfer resistances calculated to select the best configuration for the electroanalytical application. A voltammetric screening method for Mn2+ using differential pulse cathodic stripping voltammetry was developed with no preconcentration required with the SPEs L1: CB + L2: D + BDD (chlorinated) and CB + D + BDD (plain). The method exhibited broad linear ranges (1–100 and 10–100 µM) and low limits of detections (0.18 and 0.06 µM), for each SPE configuration, respectively, making it suitable for detecting Mn2+ in contaminated environmental water samples. The electrochemical responses showed good stability across all SPEs produced, with a relative standard deviation of less than 10% (N = 3), whether using the same or different electrodes. Interference studies with other metals confirmed the high selectivity of the proposed sensor. Additionally, Mn2+ was successfully detected in spiked river and lake water samples, achieving recoveries close to 100%. The analytical performance demonstrates strong potential as a simple, rapid, and selective screening method for manganese detection in environmental samples

Diamond and DLC Layers for a Wide Range of Aplications

Diamond and diamond-like carbon (DLC) layers are nowadays of increasing importance for electrical and mechanical applications. In our laboratory we grow diamond on different substrates (Si, WC-Co) using Hot Filament Chemical Vapor Deposition (HF CVD)method improved by double biasing and DLC layers using pulsed arc system again on different substrates (Si, Ni, glass, Ti-6Al-4V, steel, WCCo). Growth parameters facilitate to control crystallinity of diamond layers from microcrystalline to nanocrystalline type. Mechanical, electrical and optical parameters are possible to change using doping with hydrogen, nitrogen, or oxygen. The goal of this article is to summarize recent results achieved in our laboratory related to applications of diamond and DLC layers for their use in sensors of hard metal in water and medical implantable joints