Electrochemical study of carboxylic acids with Nb-supported boron doped diamond anode. Part 2: Electrochemical oxidation associated to DFT calculations

The Mechanism of Oxidation of Formic Acid in Acidic Solutions on Boron‐Doped Diamond Electrodes: A Quantum Chemical Study

“…[13] Our assumption of an outer sphere mechanism is based on the facts that under experimental conditions the BDD surface is passivated, which prohibits HO adsorption, and also that the oxidation of oxalic acid sets in at the potential where HO radical is generated. The latter is clearly seen in Figures 2 and 3 in the work of Huitle et al, [4] where the oxidation of oxalic acid and formic acid start at the same potential, which coincides with the potential where HO generation begins as well as with the value calculated by thermodynamics. [14] Some earlier theoretical study reinforce our assumption that this process proceeds via an outer sphere mechanism: It was concluded from the results of DFT calculations performed for the HO radical near the oxygenterminated diamond electrodes modeled with a slab.…”

“…[1-6and refs therein] In the case of electrochemical combustion of organic compounds two mechanisms of oxidation are discussed in the literature: a) a direct transfer of an electron from the molecule to the electrode, b) formation of a reactive HO radical by oxidation of water at an electrode, which then reacts with the organic molecule in solution. [1][2][3][4][5][6][7][8][9][10][11][12] The former is possible if the reactant can adsorb on the electrode surface, for example on Au or Pt, while the second mechanism is expected to prevail at special inert electrodes with low adsorption properties. A typical example of the latter is the boron-doped diamond (BDD) electrode, on which the hydroxyl radical generation and incineration of carboxylic acids can proceed via an outer sphere mechanism, without adsorption of intermediates.…”

Electrochemical measurements and theoretical studies for understanding the behavior of catechol, resorcinol and hydroquinone on the boron doped diamond surface

“…13,20 Although several mechanisms regarding the oxidation of Phs were described, 1,6,7,11,13 more work needs to be done to fully characterize the electrochemical oxidation reactions of these compounds. In this frame, computational theoretical studies, by using Density Functional Theory (DFT), emerge as a power tool to verify the possible factors that guide the electrochemical reactions, [21][22][23][24][25][26] at chemical molecular level during their detection/quantication or partial/complete oxidation at BDD electrode, for possible optimizations.…”

Evaluation of degradation mechanism of chlorhexidine by means of Density Functional Theory calculations

“…Computational chemistry has been reported as an efficient tool to clarify kinetic and thermodynamic processes involved in synthesis, properties characterization (Matencio et al, 2017;Berzins et al, 2016) and degradation pathways of molecules and structures, especially pharmaceutical drugs (Silva et al, 2017;Rapolu et al, 2015). Its combination with experimental techniques appears as an interesting study field, since degradation products could become their use unfeasible.…”

“…Its combination with experimental techniques appears as an interesting study field, since degradation products could become their use unfeasible. Indeed, electrochemical behavior and oxidation reactions could be better understood in association with theoretical evaluations (Silva et al, 2017). There are different proposed structural forms of neutral CHD, as shown in Fig.…”