SECM Studies on the Electrocatalytic Oxidation of Glycerol at Copper Electrodes in Alkaline Medium

Abstract

This study aims at analyzing the reaction mechanism of the electrooxidation of glycerol at copper surfaces in NaOH solutions using Scanning Electrochemical Microscopy (SECM) in the substrate generation/tip collection (SG/TC) mode. Experiments showed the dependence of the current at the tip on the distance between generator and tip, as well as on the concentration of the NaOH solution. The current at the tip decreased significantly after addition of glycerol, as a result of the competition between diffusion of the free‐soluble Cu(III) species and its consumption during the diffusion in the solution. The determination of the analyte in a castor biodiesel sample employing a single copper microelectrode was carried out.

Perovskite oxides as electrocatalyst for glycerol oxidation

“…No-noble metals as Ni, Cu and Co have also presented activity as catalysts for alcohol oxidation [11][12][13][14][15] . Some results have indicated that the addition of transition metal oxides to Pd and Pt catalysts can contribute to enhance its alcohol oxidation ability.…”

Amperometric determination of hydrogen peroxide using a copper microelectrode

“…[6][7][8][9][10] The use of copper surfaces to promote reduction/oxidation processes has been explored as copper oxide layers have a role in typical electrocatalytic processes. 11,12 Hence, several studies have been reported in the literature on the use of copper surfaces aiming at the quantication of different species such as glucose, 13 carbohydrates, 14 ethanol, [15][16][17] nitrate, [18][19][20] nitrite, 21 sulte, 22 glyphosate 23,24 and selenium(IV). 25 The electroreduction of H 2 O 2 at copper surfaces has also been examined and the process is facilitated due to an electrocatalytic process involving reduced copper oxides.…”

Copper Nanoparticles Dotted on Copper Sulfide Nanosheets for Selective Electrocatalytic Oxidation of Glycerol to Formate

“…CV curves of Cu-CuS/BM in 0.1 M KOH with and without 0.1 M GLY are shown in Figure S7. In the 0.1 M KOH electrolyte, Cu is oxidized to Cu­(I) at 0.66 V vs RHE, and Cu or Cu­(I) is oxidized to Cu­(II) at 0.9 V vs RHE. , After the addition of 0.1 M GLY, an enhancement of the current and a decrease in cathodic signal were observed in the range of Cu­(II), which indicated that Cu­(II) participates in the GOR. As shown in Figure a, the current density gradually increased when the applied potential increased from 1 to 1.3 V, indicating that the GOR was initiated.…”

“…In addition, Cu has a variety of valence states, and the conversion between different valance states of Cu can effectively catalyze electrochemical reactions. For example, Cu­(II) can be oxidized to Cu­(III) to participate in the oxidation of glucose or GLY, and Cu­(III) can be reduced to Cu­(II). − Some researchers have prepared effective Cu-based catalysts for the oxidation of GLY, but the improvement of current density still faces challenges. , CuS not only has the ability to adjust the interaction of electrons but also can be used as a carrier to uniformly disperse the active species due to the large specific surface area, , which can increase the density of active sites. The characteristics of CuS have been used in biosensors, electrocatalytic hydrogen evolution, and batteries .…”