Two-electron oxidation of water to form hydrogen peroxide catalysed by silicon-porphyrins

Abstract

Under basic condition, SiTPyP(O−)2 exerts two-electron oxidation of water to form hydrogen peroxide as the primary product in aqueous acetonitrile, which is initiated through one-electron oxidized process on the electrode with faradaic yield of 84–92%.

Promotive Effect of Bicarbonate Ion on Two‐Electron Water Oxidation to Form H2O2 Catalyzed by Aluminum Porphyrins

“…A part of H 2 O 2 could be incorporated into AlTMPyP by the complex formation during neutralization of the sample, depending on the concentration of H 2 O 2 , thus leading to a difficulty of quantitative discussion. Therefore, a more precise determination of the total amount of peroxides ([Peroxides] total ), including both H 2 O 2 and AlTMPyP(OOH), was performed by using permanganate titration with standardized KMnO 4 solution as reported previously …”

“…Although ordinary electrochemical water oxidation through simultaneous multiple‐electron transfer from molecular catalysts is not affected by the photon‐flux density issue, a stepwise photochemical four‐electron oxidation is affected. In this context, the catalytic reactions initiated by a one‐electron process on an electrode can provide a way for the primary process in photochemical water oxidation to avoid the photon‐flux‐density problem. In the present study, we have performed a detailed study on the effect of bicarbonate and carbonate ions in the two‐electron water oxidation initiated by one‐electron electrochemical oxidation of a molecular catalyst.…”

“…To avoid this bottleneck, one alternative approach is to develop a one‐electron‐induced pathway of water oxidation that completes within the one‐electron oxidation step and does not need to wait for the next photon . In this context we have investigated a two‐electron water oxidation initiated through one‐electron oxidation of catalysts to form H 2 O 2 catalyzed by metalloporphyrins centered with earth‐abundant elements such as Al III , Si IV , and Sn IV[21] . In addition to the novel approach of water oxidation initiated through a one‐electron process, which enables a one‐photon‐induced process to avoid the bottleneck, a more favorable energy accumulation by the H 2 O 2 /H 2 couple (+341 kJ mol −1 ) compared with the conventional O 2 /H 2 couple (243 kJ mol −1 ) as well as the utilization of abundant elements such as Al III[19] and Si IV[20] ions as the reaction center strongly motivated us to further develop the two‐electron oxidation of water to form H 2 O 2 .…”

Role of Lipid Peroxidation Process in Neurodegenerative Disorders

“…The LOOH are targeted to various reduction reactions; which lead to either inhibition of peroxidative damage and/or induction of peroxidative damage [3]. The inhibition of peroxidative damage is due to decomposing of hydroperoxides, namely two-electron reduction [26]. Some of the enzymes are responsible for this two-electron reduction process of hydroperoxides.…”

Organic electronic materials for hydrogen peroxide production

“…"trapping" H2O2 molecules in the porous areas where they can be reduced further to H2O before being removed from the catalyst/electrolyte interface. 75 or separated with ion selective membrane 76 or ceramic frit 77 .…”