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Water oxidation is a multielectron complex reaction that produces molecular oxygen as the final product. The article addresses the lack of confirmation of oxygen product formation in electrochemical oxygen evolution reaction (OER) studies, despite the extensive research conducted on catalysts for water splitting. It critically evaluates the trend observed in many studies that solely rely on electrochemical methods for OER quantification without confirming the oxygen product via complementary analytical techniques. The omission of measuring evolved oxygen gas leaves a crucial gap in the quantification of the OER process and raises concerns about the validity and accuracy of reported results. Analytical techniques, such as gas chromatography, Rotating Ring-Disk Electrode (RRDE), fluorescence oxygen probes, Clark electrode, and volumetry are critically analyzed and described to ensure the reliability and credibility of voltammetry and bulk electrolysis to provide a more accurate assessment of the OER process. [ABSTRACT FROM AUTHOR]

Traditional homogeneous water oxidation catalysts are plagued by instability under the reaction conditions. We report that the complex [[[Co.sub.4][([H.sub.2]O).sub.2][([PW.sub.9][O.sub.34]).sub.2]].sup.10- ], comprising a [Co.sub.4][O.sub.4] core stabilized by oxidatively resistant polytungstate ligands, is a hydrolytically and oxidative[y stable homogeneous water oxidation catalyst that self-assembles in water from salts of earth-abundant elements (Co, W, and P). With [[Ru[(bpy).sub.3]].sup.3+] (bpy is 2,2'-bipyridine) as the oxidant, we observe catalytic turnover frequencies for [O.sub.2] production [greater than or equal to]5 [s.sup.-1] at pH = 8. The rate's pH sensitivity reflects the pH dependence of the four-electron [O.sub.2]-[H.sub.2]O couple. Extensive spectroscopic, electrochemical, and inhibition studies firmly indicate that [[[Co.sub.4][([H.sub.2]O).sub.2][([PW.sub.9][O.sub.34]).sub.2]].sup.10-] is stable under catalytic turnover conditions: Neither hydrated cobalt ions nor cobalt hydroxide/oxide particles form in situ. 10.1126/science.1185372

Two terminal Au-oxo compounds are prepared and characterized by many physicochemical methods. These two compounds have established that both solids are diamagnetic and [super 31]P and [super 17]O NMR spectroscopy has confirmed that both have remained diamagnetic in solution.

An isostructural series of 1 electron-reduced donors are kept under observation to gain the basic knowledge about the mechanism involved in the reduction of [O.sub.2] to superoxide anion ([O.sub.2.sup..-]) in water by heteropolytungstate cluster-anions and the effect of donor-ion charge on it. The results show that with an increase in the negativity of the anions, the anionic repulsions in the 'successor-complex' ion pairs also rises, hence limiting the use of heteropolytungstate charge to control such reductions under turnover conditions.

The reaction of ebselen and its derivatives with peroxynitrite anion (PN) is studied in the gas and aqueous phases. It is observed that ebselen reacts with PN to exhibit glutatione peroxidase activity.

The article explains the various mechanisms that are involved in the concerted proton-electron transfer (CPET) taking place during the homogeneous reduction of dioxygen to water. The CPET is shown to significantly decreases with decrease in the endergonicity of ET.

The main properties of the water oxidation catalyst [Rb.sub.8][K.sub.2][{[Ru.sub.4.sup.IV][O.sub.4][(OH).sub.2][([H.sub.2]O).sub.4]}[([gamma]-Si[W.sub.10][O.sub.36]).sub.2] and its mechanism of water oxidation are described. Spectroscopic, scattering and chemical experiments have shown that the catalyst is stable in solution and under catalytic turnover conditions, but it has decomposed slowly in acidic aqueous solutions.

A totally homogeneous, molecular, visible-light-driven water oxidation system is described, where the three system components are a water oxidation catalyst, a photosensitizer and a sacrificial electron acceptor. Dioxygen is formed with an initial turnover frequency of 8 * [10.sup.-2] [s.sup.-1] and a quantum field of 9%.