Water oxidation catalysis – role of redox and structural dynamics in biological photosynthesis and inorganic manganese oxides

Zaharieva, Ivelina; González-Flores, Diego; Asfari, B.; Pasquini, Chiara; Mohammadi, Mohammad Reza; Klingan, Katharina; Zizak, Ivo; Loos, Stefan; Chernev, Petko; Dau, Holger

doi:10.1039/c6ee01222a

Cited by 115 publications

(197 citation statements)

References 63 publications

Supporting

Mentioning

159

Contrasting

Unclassified

Order By: Relevance

“…Of special interest is the structure and construction of the oxygen‐evolving catalyst, which plays a leading role in the process of water oxidation and is contained in the PSII. Understanding the selfassembly process of the OEC is of high importance for the development of artificial catalysts showing attractive self‐assembly and self‐healing properties . Moreover, the cubane structure of the oxygen‐evolving complex is an inspiration for the design of PSII mimics to gain fuels such as hydrogen from water with the aid of light.…”

Section: Introductionmentioning

confidence: 99%

Investigating the Structure and Dynamics of Apo‐Photosystem II

et al. 2019

View full text Add to dashboard Cite

Photosynthetic water oxidation is a model for future technologies employing solar energy to split water into hydrogen and oxygen. Natural water oxidation is carried out by a special manganese catalyst, the water‐oxidizing complex (WOC), located in photosystem II (PSII) of cyanobacteria, algae, and plants. Hence, there is great interest in the molecular structure as well as structural changes during catalytic activity and assembly/disassembly of the WOC. In particular, the light‐driven assembly during photosystem II repair under physiological conditions is poorly understood, and structural information about manganese depleted PSII (apo‐PSII) is required as a starting point for improving this understanding. Recently Zhang et al. (eLife 2017;6:e26933) showed that the cavity harboring the WOC in PSII remains largely intact upon manganese‐depletion and suggested that deprotonation of hydrogen‐bonding pairs enables the charge‐compensated insertion of the manganese cations without any major change of the cavity structure. By computational methods we have further investigated the structure of apo‐PSII and show how it can be stabilized by protons localized at the terminal carboxylate groups inside the remaining cavity. Ab‐initio molecular dynamics simulations suggest that not more than two water molecules fill the void left by manganese depletion.

show abstract

Section: Introductionmentioning

confidence: 99%

Investigating the Structure and Dynamics of Apo‐Photosystem II

et al. 2019

View full text Add to dashboard Cite

show abstract

“…These findings are unexpected given the structural similarities between the biogenic materials and birnessite (vide supra), which is recognised as a catalytically active phase of manganese oxide solids during water electrooxidation . Heat‐treatment of the electrodes to increase the Mn III contribution (Figure and Figure S1 in the Supporting Information), which is critical for efficient catalysts of water oxidation, did not improve the activity of the biogenic MnO x . At the same time, continuous polarisation at very positive potentials, namely, >1.9 V vs. RHE, slightly enhanced the electrocatalytic capacity of the Ca:MnO x and MnO x materials (Figure ).…”

Section: Resultsmentioning

confidence: 93%

Tunable Biogenic Manganese Oxides

Simonov

Hocking

Tao

et al. 2017

Chemistry A European J

View full text Add to dashboard Cite

Influence of the conditions for aerobic oxidation of Mn2+(aq) catalysed by the MnxEFG protein complex on the morphology, structure and reactivity of the resulting biogenic manganese oxides (MnO ) is explored. Physical characterisation of MnO includes scanning and transmission electron microscopy, and X-ray photoelectron and K-edge Mn, Fe X-ray absorption spectroscopy. This characterisation reveals that the MnO materials share the structural features of birnessite, yet differ in the degree of structural disorder. Importantly, these biogenic products exhibit strikingly different morphologies that can be easily controlled. Changing the substrate-to-protein ratio produces MnO either as nm-thin sheets, or rods with diameters below 20 nm, or a combination of the two. Mineralisation in solutions that contain Fe2+(aq) makes solids with significant disorder in the structure, while the presence of Ca2+(aq) facilitates formation of more ordered materials. The (photo)oxidation and (photo)electrocatalytic capacity of the MnO minerals is examined and correlated with their structural properties.

show abstract

“…Smaller charge transfer resistance ( R ct, trap ) was measured under light illumination on the three catalyst‐loaded electrodes due to their photoactive properties . Meanwhile, the observation of the smallest charge transfer resistance on FeOOH@carbon‐ring‐C 3 N 4 surface was due probably to the enhanced photogenerated electron–hole separation efficacy …”

Section: Resultsmentioning

confidence: 95%

Photoactuation Healing of α‐FeOOH@g‐C₃N₄ Catalyst for Efficient and Stable Activation of Persulfate

Zhang

Zong-hua

Liu

et al. 2017

Small

View full text Add to dashboard Cite

Inspired by living systems, the construction of smart devices that can self-heal in response to structural damage is a promising technology for maintaining the high activity and stability of catalysts during heterocatalytic reactions. Here this study demonstrates an ingenious platform that enabled efficient persulfate (PS) activation for contaminant degradation via integrating a catalyst with photoactuation regeneration. Under irradiation, it is unambiguously confirmed that the collective properties of a tailored FeOOH@C N catalyst permit interfacial photoexcited electron transport from the photocatalyst substrate to needle-shaped FeOOH. This results in the simultaneous recovery of Fe(III) and optimization of the Fe(II)/Fe(III) ratio on FeOOH surface during PS activation process, so that the healed chemical structure ensures that subsequent PS activation remains unimpaired. Aqueous organic contaminant (bisphenol A) oxidation efficacy in this system is almost 20 times higher than for photo- or Fenton-oxidation alone. This work highlights the concept of catalyst regeneration for stable reactive species generation in solution, which represents alternative application of photocatalysis for practical environmental remediation. Further, the photoactuation healing approach can be expanded into various domains, such as material fabrication or chemical synthesis.

show abstract

Water oxidation catalysis – role of redox and structural dynamics in biological photosynthesis and inorganic manganese oxides

Abstract: Water oxidation is pivotal in biological photosynthesis, where it is catalyzed by a protein-bound metal complex with a Mn4Ca-oxide core; related synthetic catalysts may become key components in non-fossil fuel technologies.

Cited by 115 publications

References 63 publications

Investigating the Structure and Dynamics of Apo‐Photosystem II

Investigating the Structure and Dynamics of Apo‐Photosystem II

Tunable Biogenic Manganese Oxides

Photoactuation Healing of α‐FeOOH@g‐C₃N₄ Catalyst for Efficient and Stable Activation of Persulfate

Contact Info

Product

Resources

About

Water oxidation catalysis – role of redox and structural dynamics in biological photosynthesis and inorganic manganese oxides

Abstract: Water oxidation is pivotal in biological photosynthesis, where it is catalyzed by a protein-bound metal complex with a Mn4Ca-oxide core; related synthetic catalysts may become key components in non-fossil fuel technologies.

Cited by 115 publications

References 63 publications

Investigating the Structure and Dynamics of Apo‐Photosystem II

Investigating the Structure and Dynamics of Apo‐Photosystem II

Tunable Biogenic Manganese Oxides

Photoactuation Healing of α‐FeOOH@g‐C3N4 Catalyst for Efficient and Stable Activation of Persulfate

Contact Info

Product

Resources

About

Photoactuation Healing of α‐FeOOH@g‐C₃N₄ Catalyst for Efficient and Stable Activation of Persulfate