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Edward Thomas, Leo Carr says (September 4), may not have wished to be labelled Welsh, but R. S. Thomas certainly found a rich seam of Welshness running through his namesake's [...]

The development of manganese-based water oxidation electrocatalysts is desirable for the production of solar fuels, as manganese is earth-abundant, inexpensive, non-toxic, and has been employed by the Photosystem II in nature for a billion years. Herein, we directly constructed a 3 D nanoarchitectured turbostratic δ-MnO x on carbon nanotube-modified nickel foam (MnO x/CNT/NF) by electrodeposition and a subsequent annealing process. The MnO x/CNT/NF electrode gives a benchmark catalytic current density (10 mA cm−2) at an overpotential ( η) of 270 mV under alkaline conditions. A steady current density of 19 mA cm−2 is obtained during electrolysis at 1.53 V for 1.0 h. To the best of our knowledge, this work represents the most efficient manganese-oxide-based water oxidation electrode and demonstrates that manganese oxides, as a structural and functional model of oxygen-evolving complex (OEC) in Photosystem II, can also become comparable to those of most Ni- and Co-based catalysts. [ABSTRACT FROM AUTHOR]

Iron porphyrins Fe-pE, Fe-mE, and Fe-oE were synthesized and their electrochemical behavior for CO2 reduction to CO has been investigated. The controlled potential electrolysis of Fe-mE gave exclusive 65% Faradaic efficiency (FE) whereas Fe-oE achieved quasi-quantitative 98% FE (2% H2) for CO production. [ABSTRACT FROM AUTHOR]

Ni‐nanocarbon‐based hybrid materials are prepared by a two‐step simple synthetic route and investigated as an oxygen evolution reaction (OER) electrocatalyst, exhibiting low overpotential, small Tafel slope 32 mV dec–1 and a high turnover frequency ≈16 s−1 based on the Ni metal. [ABSTRACT FROM AUTHOR]

A simple strategy to immobilize highly efficient ruthenium based molecular water-oxidation catalysts on the basal-plane pyrolytic graphite electrode (BPG) by polymerization has been demonstrated. The electrode 1@BPG has obtained a high initial turnover frequency (TOF) of 10.47 s−1 at ∼700 mV overpotential, and a high turnover number (TON) up to 31600 in 1 h electrolysis. [ABSTRACT FROM AUTHOR]

Electrochemically driven water oxidation has been performed using a molecular water oxidation catalyst immobilized on hybrid carbon nanotubes and nano-material electrodes. A high turnover frequency (TOF) of 7.6 s-1 together with a high catalytic current density of 2.2 mA cm-2 was successfully obtained at an overpotential of 480 mV after 1 h of bulk electrolysis. [ABSTRACT FROM AUTHOR]

In article number 1600516, Licheng Sun and co‐workers describe a clean and renewable energy system: highly efficient hybrid water oxidation catalyst based on carbon nanotubes and Ni(OH)2 nano‐plates. The image shows the work towards a highly efficient hybrid catalyst for water oxidation. By using this hybrid catalyst, water molecules can be efficiently oxidized to generate oxygen bubbles. [ABSTRACT FROM AUTHOR]

A series of molecularly engineered and novel dyes WS1, WS2, WS3, and WS4, based on the D35 donor, 1-(4-hexylphenyl)-2,5-di(thiophen-2-yl)-1 H -pyrrole and 4-(4-hexylphenyl)-4 H -dithieno[3,2- b :2',3'- d ]pyrrole as π-conjugating linkers, were synthesized and compared to the well-known LEG4 dye. The performance of the dyes was investigated in combination with an electrolyte based on Co(II/III) complexes as redox shuttles. The electron recombination between the redox mediators in the electrolyte and the TiO 2 interface decreases upon the introduction of 4-hexylybenzene entities on the 2,5-di(thiophen-2-yl)-1 H -pyrrole and 4 H -dithieno[3,2- b :2',3'- d ]pyrrole linker units, probably because of steric hindrance. The open circuit photovoltage of WS1-, WS2-, WS3-, and WS4-based devices in combination with the Co(II/III)-based electrolyte are consistently higher than those based on a I - /I 3 - electrolyte by 105, 147, 167, and 75 mV, respectively. The WS3-based devices show the highest power conversion efficiency of 7.4% at AM 1.5 G 100 mW/cm 2 illumination mainly attributable to the high open-circuit voltage ( V OC )., Competing Interests: The authors declare no competing financial interest.

The development of manganese-based water oxidation electrocatalysts is desirable for the production of solar fuels, as manganese is earth-abundant, inexpensive, non-toxic, and has been employed by the Photosystem II in nature for a billion years. Herein, we directly constructed a 3 D nanoarchitectured turbostratic δ-MnO x on carbon nanotube-modified nickel foam (MnO x /CNT/NF) by electrodeposition and a subsequent annealing process. The MnO x /CNT/NF electrode gives a benchmark catalytic current density (10 mA cm -2 ) at an overpotential (η) of 270 mV under alkaline conditions. A steady current density of 19 mA cm -2 is obtained during electrolysis at 1.53 V for 1.0 h. To the best of our knowledge, this work represents the most efficient manganese-oxide-based water oxidation electrode and demonstrates that manganese oxides, as a structural and functional model of oxygen-evolving complex (OEC) in Photosystem II, can also become comparable to those of most Ni- and Co-based catalysts., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Noble-metal-free bimetal-based electrocatalysts have shown high efficiency for water oxidation. Ni and/or Co in these electrocatalysts are essential to provide a conductive, high-surface area and a chemically stable host. However, the necessity of Ni or Co limits the scope of low-cost electrocatalysts. Herein, we report a hierarchical hollow FeV composite, which is Ni- and Co-free and highly efficient for electrocatalytic water oxidation with low overpotential 390 mV (10 mA cm -2 catalytic current density), low Tafel slope of 36.7 mV dec -1 , and a considerable durability. This work provides a novel and efficient catalyst, and greatly expands the scope of low-cost Fe-based electrocatalysts for water splitting without need of Ni or Co., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Iron porphyrins Fe-pE, Fe-mE, and Fe-oE were synthesized and their electrochemical behavior for CO 2 reduction to CO has been investigated. The controlled potential electrolysis of Fe-mE gave exclusive 65% Faradaic efficiency (FE) whereas Fe-oE achieved quasi-quantitative 98% FE (2% H 2 ) for CO production.