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Electrodeposited NiCoCr ternary alloy is explored as a cost‐effective and Earth‐abundant alternative electrocatalyst for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline conditions. Different metal salt concentrations (between 10 and 100 mM) and cathodic current densities (between 75 and 225 mA cm−2) are tested to prepare an optimized material exhibiting both the best electrocatalytic efficiency and robustness for water splitting. Combining electrochemistry with complementary physicochemical characterizations (scanning electron microscopy, energy‐dispersive X‐ray spectroscopy analysis, and X‐ray photoelectron spectroscopy) has enabled to gain a deep knowledge of the composition, morphology, and catalytic activity before and after long‐term electrolytic tests. Compared with the related NiCo and NiCr binary alloys, NiCoCr shows catalytic performance for HER similar to NiCr and higher than that of NiCo. In contrast, its catalytic activity for OER is quite comparable to that of NiCo and higher than that of NiCr. Importantly, the presence of Cr is found to be beneficial to increase the oxidation resistance of the ternary alloy. This work provides a scalable way to produce bifunctional and robust electrode materials. [ABSTRACT FROM AUTHOR]

BiVO4 is a promising n‐type semiconductor for water‐splitting photoelectrochemical cells. We report here a new method to prepare BiVO4 photoanodes that is based on an alkaline electrodeposition process, which avoids chemical etching of Bi. In addition, we present a simple and general method to prepare coatings of amorphous FeOx that behave as a co‐catalyst on our BiVO4 material, improving the water splitting photocurrent. Split personality: A method is reported for preparing photoelectrochemically active BiVO4 coatings, based on the electrodeposition of metal Bi in a highly alkaline electrolyte. In addition, a versatile technique to deposit catalytic coatings of amorphous FeOx is applied to the so‐created BiVO4 material to produce water‐splitting photoanodes. [ABSTRACT FROM AUTHOR]

We present the design of AND and OR logic gates made with silicon and carbon materials and operated by bipolar electrochemistry. Such devices require electrical and light inputs to function and generate an electrical output or, alternatively, an optical output that can be readily observed with the naked eye. These operators are stable over time and can work in a wide range of electrolyte concentrations. Finally, we show that the input electrical potential can be considerably lowered in the presence of the FeIII(CN)63−/FeII(CN)64− redox couple in solution. [ABSTRACT FROM AUTHOR]

One of the major aspects and advantages of solar energy conversion is the photocatalytic hydrogen generation using semiconductor materials for an eco-friendly technology. Designing a low-cost efficient material to overcome limited light absorption as well as rapid recombination of photogenerated charge carriers is essential to achieve considerable hydrogen generation. In recent years, sulfide based semiconductors have attracted scientific research interest due to their excellent solar response and narrow band gap. The present review focuses on the recent approaches in the development of hierarchical ternary sulfide based photocatalysts with a special focus on ZnIn2S4. We also observe how the electronic structure of ZnIn2S4 is beneficial for water splitting and the various strategies involved for improving the material efficiency for photocatalytic hydrogen generation. The review places emphasis on the latest advancement/new insights on ZnIn2S4 being used as an efficient material for hydrogen generation through photocatalytic water splitting. Recent progress on essential aspects which govern light absorption, charge separation and transport are also discussed in detail. [ABSTRACT FROM AUTHOR]

Like photosynthesis, where light is transformed into energy‐rich molecules, sunlight energy can be converted into H2 and O2 using water‐splitting photoelectrochemical cells (PECs). These systems are highly promising to produce H2 without carbon emissions, however, their fabrication is still based on expensive fabrication procedures and nonabundant materials, which prevents their manufacturing and study by many laboratories. Here, an original concept for preparing monolithic water‐splitting PECs based on the integration of a low‐cost Si photovoltaic (PV) panel with two Si‐based photoelectrodes fabricated by simple procedures and earth‐abundant materials is demonstrated. In contrast with previous approaches, in the present system, the PV solid junction and the two solid/liquid junctions participate in the creation of the effective photovoltage applied for water splitting. This simple device that can split water from various electrolytes for several hours should promote new advances in the field of solar fuels. A robust general concept for monolithic photoelectrochemical cells is reported, which is employed to split water under solar irradiation without the application of an external bias. It allows preparing complete water splitting cells by simple means at a low cost. This design should lead to considerable improvements in the field of solar fuels. [ABSTRACT FROM AUTHOR]

AND and OR logic gates are made with silicon and carbon materials and operated by using bipolar electrochemistry. Such devices require electrical and light inputs to function and generate an electrical output or, alternatively, an optical output that can be readily observed with the naked eye. (Image courtesy of J.‐F. Bergamini). More information can be found in the Communication by G. Loget and B. Fabre on page 366 in Issue 3, 2016 (DOI: 10.1002/celc.201500345). [ABSTRACT FROM AUTHOR]