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[Display omitted] The anodic oxygen evolution reaction is a well-acknowledged side reaction in traditional aqueous electrochemiluminescence (ECL) systems due to the generation and surface aggregation of oxygen at the electrode, which detrimentally impacts the stability and efficiency of ECL emission. However, the effect of reactive oxygen species generated during water oxidation on ECL luminophores has been largely overlooked. Taking the typical luminol emitter as an example, herein, we employed NiIr single-atom alloy aerogels possessing efficient water oxidation activity as a prototype co-reaction accelerator to elucidate the relationship between ECL behavior and water oxidation reaction kinetics for the first time. By regulating the concentration of hydroxide ions in the electrolyte, the electrochemical oxidation processes of both luminol and water are finely tuned. When the concentration of hydroxide ions in electrolyte is low, the kinetics of water oxidation is attenuated, which limits the generation of oxygen, effectively mitigates the influence of oxygen accumulation on the ECL strength, and offers a novel perspective for harnessing side reactions in ECL systems. Finally, a sensitive and stable sensor for antioxidant detection was constructed and applied to the practical sample detection. [ABSTRACT FROM AUTHOR]

The emergence of hydrogel evaporators has greatly improved the evaporation rate and has attracted widespread attention. However, single-strategy design yields limited evaporation rates and anti-fouling properties, restricting their utility. Here, we report a superhydrophilic interconnected porous hydrogel (SIPH) evaporator that incorporates multiple strategirs. This design enhances water transport, light absorption, and heat localization, reducing heat loss from the evaporating surfaces. By modulating polymer network-water interactions with −NH 2 groups, we achieved a high proportion of activated water, lowering the evaporation enthalpy to about one-third that of pure water. Based on this diversified design, SIPH achieves a high evaporation rate of 4.80 kg m−2 h−1 under one sun. Moreover, SIPH demonstrates excellent stability in various water qualities and long-lasting anti-pollution properties, offering significant practical application potential. [Display omitted] • Interconnected porous structure enhances light absorption and water transport. • Excellent thermal localization concentrates heat on the evaporating surface. • Hydratable polymer network greatly reduces the evaporation enthalpy. • Evaporation rate of 4.80 kg m−2 h−1 and energy efficiency of 95.0 % were obtained. • A stable evaporation rate and excellent anti-pollution ability were achieved. [ABSTRACT FROM AUTHOR]

Catalytic H 2 production from CH 3 OH and H 2 O is acknowledged as a promising strategy in the growth of future hydrogen economy, yet its industrialization still faces significant challenges of substantial energy consumption. To overcome the high barrier of CH 3 OH/H 2 O activation, we report a low-cost plasmonic Co–Cu alloy catalyst for producing H 2 efficiently through a light-driven process, bringing an outstanding generation rate of 6225.1 μmol g−1 min−1 (31.1 μmol min−1) without external thermal energy input. The bifunctional nature of Co active sites on Cu favors the adsorption of CH 3 OH and lowers the energy barrier for H 2 O dissociation simultaneously. Moreover, the Co–Cu interface exploits the hot-carrier-induced reactant activation upon visible light irradiation, enormously decreasing the apparent activation energy from 100.8 to 68.2 kJ mol−1. Our study unveils a novel method to harness renewable solar energy for H 2 production, and will provide numerous opportunities for constructing a robust and sustainable catalytic process. [Display omitted] • CoCu bimetallic catalyst was employed to produce H 2 from CH 3 OH and H 2 O under only solar light. • The H 2 production rate of 6225.1 μmol g−1 min−1 can be achieved under solar light irradiation. • The Co active site on Cu favored the adsorption of CH 3 OH and lowered the energy barrier for H 2 O dissociation. • Photo-induced hot carries on Co–Cu interface decreased Ea significantly. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mo- Eu-doped ZrO 2 acts as proton conductor increasing the WGS catalyst' activity. • The structuration of the catalyst leads to higher conversions. • Structured catalysts demonstrate the promoter effect is caused by proton conductor. • Promoted WGS catalysts very promising for H 2 technology mobile devices. Proton conductors Mo-Eu-Zr mixed oxide systems were synthesized and further mixed with a conventional Pt/CeO 2 /Al 2 O 3 catalyst to develop a highly efficient water-gas-shift (WGS) catalyst. The designed catalyst, once structured, allows reach the equilibrium conversion at medium temperatures (∼350 °C) at 80 L·g−1 h−1 space velocity. The ability of the proton conductor to maintain an elevated water concentration at the metal-support interface by Grotthuss' mechanism boosts the catalytic activity in WGS reaction. The Mo-containing proton conductor is extensively characterized allowing to establish the formation of molybdenum oxide phases nucleating on top of the Eu sites in Eu-Zr oxide solid solution. [MoO 4 ]2− to [Mo 7 O 24 ]6− clusters nucleates at low Mo contents resulting in a α-MoO 3 layer on increasing its content. In presence of H 2 , Mo-bronzes are formed from ∼200 °C enhancing water concentration at the surfaces and boosting the catalytic activity in the WGS reaction. These results pave the way for developing lower volume WGS reactors. [ABSTRACT FROM AUTHOR]

Enhancing the photoreduction of carbon dioxide (CO 2) to produce valuable chemicals, such as carbon monoxide (CO), is of significant importance. The bottleneck in developing advanced catalysts lies in the rational design of catalytic centers with efficient CO 2 activation and hydrogen proton production. In this work, palladium nanoparticles (Pd NPs) were successfully modified on UiO-66-NH 2 -Zn SAs (UN-Zn SAs) by a photo-deposition method. The optimized photocatalyst, 4 Pd NPs-UN-0.7Zn SAs, demonstrated exceptional performance in converting CO 2 to CO, exhibiting approximately 1.4-fold and 7.8-fold enhancements compared to UN-0.7Zn SAs and UN, respectively. A combination of time-resolved photoluminescence spectroscopy and electron paramagnetic resonance results unveiled that the introduction of Pd NPs effectively promoted the photogenerated charge separation and facilitated water activation to produce more hydrogen protons. The generated hydrogen protons were subsequently coupled with nearby CO 2 that was activated by Zn SAs, thus achieving the facile water-activation-induced CO 2 reduction process. Theoretical calculations further confirmed that the heterogeneous synergistic effects between Zn SAs and Pd NPs lowered the energy barrier for the rate-limiting step of CO 2 conversion to COOH* , thereby achieving efficient photocatalytic CO 2 reduction reactions. This work provides a new perspective on the development of efficient catalysts for the effective conversion of CO 2. • Pd NPs-UiO-66-NH2-Zn SAs were prepared via the photo-deposition method. • 4Pd NPs-UiO-66-NH2-0.7Zn SAs had excellent photocatalytic CO2 reduction performance. • The introduced Pd NPs further facilitated the photogenerated charge separation and water activation of the samples. • DFT calculations further showed that Pd NPs-UiO-66-NH2-Zn SAs lowered the energy barrier for COOH* formation. [ABSTRACT FROM AUTHOR]

Interfacial evaporation through hydrogel-based evaporators is emerging as a sustainable and cost-effective strategy for drinkable water production. Herein, a specially designed bi-layer hydrogel evaporator was fabricated and used for efficient solar water desalination. With cotton linter as cellulose precursor, it was dispersed in a highly concentrated ZnCl 2 (65 %) solution, and cross-linked by epichlorohydrin to prepare cellulose composite hydrogel. After removing inorganic salts by salt-leaching, polyaniline (PANi) with broadband and wide-range light absorption was then integrated into the top surface of hydrogel through in situ polymerization to construct a bi-layer evaporator. As a solar evaporator, the water could be evaporated with a low-energy demand, and the heat from the sunlight could be confined at the interface to achieve efficient water evaporation. Therefore, the hydrogel evaporator demonstrates an optimal water evaporation rate of 3.02 kg m−2 h−1 and photothermal conversion efficiency of 89.09 % under 1 sun (1 kW m−2) irradiation. This work provides new possibilities for efficient solar water purification systems with assured water quality. [Display omitted] [ABSTRACT FROM AUTHOR]

Cu-foils have been used intensively to fabricate graphene and other carbon nanostructures. Several routes have been implemented to improve the synthesis of such carbonaceous nanomaterials. We investigated the growth of carbon materials on Cu-foils by mapping the reactor in a chemical vapor deposition method. Several Cu-foils were pretreated by sonication to modify their surface and were placed alongside the reactor and exposed to a flow of ethanol vapor. After carbon materials deposition, the Cu-foils were analyzed by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), Raman spectroscopy, and cyclic voltammetry (CV). It was demonstrated that the type of synthesized carbon nanostructure depends strongly on the position where the Cu-foils were placed. XRD characterizations revealed the presence of graphite materials, Cu, and CuO crystal structures. SEM characterizations revealed the presence of helical, herringbone and straight multiwalled carbon nanotubes with internal bamboo-shape morphology and formation of Cu nanoparticles. Important electrochemical properties of Cu-foils rich in helical carbon nanostructures were observed, suggesting this material can be used for redox reactions (RR) promotion. In addition, the hydrophobic properties were evaluated by contact angle measurements. Image 1 [ABSTRACT FROM AUTHOR]

• A cocatalyst loading strategy is proposed for wastewater electrochemical treatment. • The cocatalyst NiOOH accelerates the charge transfer, thus promoting water oxidation. • The increased reactive oxygen species promote the electrooxidation of organics. • The electrode shows great promise for pharmaceutical wastewater treatment. Acetaminophen (APAP), a common pharmaceutical and personal care product, is highly toxic and resistant to conventional wastewater treatment. Electrochemical oxidation is a promising technique for removing pharmaceuticals and personal care products (PPCPs), and the Ti-doped α -Fe 2 O 3 electrode is a low-cost alternative to noble-metal electrocatalysts. Herein, we present a novel cocatalyst loading strategy to enhance the electrocatalytic ability of the electrodes by loading a cocatalyst, NiOOH, by electrodeposition. The cocatalyst leads to a higher potential drop (97.7%) on the Helmholtz layer than the bare one (80.5%) and accelerates the charge transfer by ten. The increased production of reactive oxygen species during water activation further facilitates the electrooxidation of APAP, resulting in a threefold increase in removal rate and a twofold increase in Faraday efficiency. Additionally, the obtained NiOOH/Ti-Fe 2 O 3 electrode shows excellent ability (100% APAP removal in 2 h) and stability (removal efficiency greater than 94% after ten cycles) for pharmaceutical wastewater treatment containing APAP. These findings provide a novel and generalized strategy for enhancing the electrocatalytic ability of Ti-doped α -Fe 2 O 3 electrodes and offer valuable guidelines for exploring efficient and economic electrocatalysts for refractory wastewater treatment. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • An opposite photocatalytic oxidation behaviors of BiOCl and TiO 2 was observed. • BiOCl tends to decomposite perhalocarboxylate by hole transfer. • TiO 2 preferred to oxidize organic pollutants mediated by hydroxyl radical. • Different photocatalytic behaviors are attributed to the surface site of reactant adsorption and hole trapping. Abstract Although all the semiconductor-based photocatalysis is initiated by photoinduced conduction band electron and valence band hole, the reaction pathway and activity of the electron and hole would be largely dependent on the type of the photocatalyst. It is essential to distinguish and understand the photocatalyst-dependence of a specific reaction. In the present study, we compared the photocatalytic behaviors of BiOCl and TiO 2 for the degradation of different pollutants including perfluorooctanoic acid (PFOA), chloroacetic acids and benzoic acid. We found that the decompositions of perhalocarboxylate acids (PHCAs) such as PFOA and trichloroacetic acid (TCA) were much rapider over BiOCl than on the TiO 2 (commercial P25). The surface-area- normalized rate constants for the oxidation of TCA have five orders of magnitude of difference between these two systems. By contrast, the degradation rates of OH-sensitive organic pollutants such as dichloroacetic acid, monochloroacetic acid and benzoic acid were much higher on the TiO 2. Moreover, much more meta-substituted hydroxylated intermediate was observed during the photocatalytic oxidation of benzoic acid on BiOCl. In addition, PFOA and TCA were degraded efficiently in the BiOCl system even in the presence of other labile organic compounds (such as acetic acid). All the experimental results definitely indicate that BiOCl photocatalyst prefers to directly oxidize the PHCAs and benzoic acid by the hole transfer, while TiO 2 tends to oxidize the solvent water molecule to OH radical. The mechanism underlying on the different activity of BiOCl and TiO 2 are further discussed. [ABSTRACT FROM AUTHOR]

The viability of water gas shift catalytic system for mobile application passes through obligatory reactor volume reduction, achieved normally by using less charge of more efficient catalyst. Completely new concept for catalyst design is proposed: a catalytic system including classically reported WGS catalysts of different nature or active phase (Cu, Pt or Au) mechanically mixed with an ionic conductor. The influence of the later on catalyst activity is studied and discussed, more precisely its effect on the rate of the reaction-limiting step and catalysts’ efficiency. It is demonstrated with this study, that the presence of an ionic conductor in contact with a WGS catalyst is essential for the water supply (dissociation and transport), thereby potentiating the water activation step, whatever the mechanism and catalyst overall performance. [ABSTRACT FROM AUTHOR]

Highlights • Shutdown Dose rate due to water activation negligible in ITER upper port interspace. • Blanket manifold shields have a large impact on shutdown dose rates in interspace. • Proposed combination of shields effectively mitigates the radiation cross-talk. Abstract In this work, the D1SUNED code has been used to characterize the shutdown dose rate (SDDR) in the ITER Upper Port (UP) interspace due to activation induced by two neutron sources: plasma prompt neutrons and 17N decay neutrons emitted from the activated cooling water conducted through the UP. Furthermore, shielding measures have been proposed to mitigate the SDDR in the UP interspace; a set of conceptual shields has been designed and inserted into the MCNP computational model C-lite v2 covering the Vacuum Vessel UP Stub Extension and the UP Connecting Duct. The results have shown that the integration of proposed shields has significantly decreased the SDDR due to the activation induced by plasma prompt neutrons, while the activation induced by 17N decay neutron has a negligible contribution to the total SDDR in the ITER UP interspace. [ABSTRACT FROM AUTHOR]

Solar-driven vapor generation by localized solar heating of a photothermal material is an environmentally friendly approach for seawater desalination and wastewater purification. In this work we designed a novel bionic evaporator, inspired by plant transpiration in nature, to realize highly efficient solar vapor generation. The plant transpiration inspired three-dimensional structure has a hydrophilic cellulose skeleton with high porosity and low thermal conductivity, and decorated with photothermal polypyrrole (PPy) that self-organize as nano branches and leaves exhibiting excellent photothermal conversion capacity. The cellulose skeleton has microchannels that facilitates water transport and reduces the water evaporation enthalpy. PPy nano branches and leaves can not only efficiently absorb and convert sunlight, but the thermal gradient distribution in this microstructure induces Marangoni convection which guarantees efficient water transportation in evaporative regions. Moreover, the coupling of external wind fields further enhances the rate of vapor escape. The as-fabricated vapor generator based on the bionic structure achieved an impressive high evaporation rate of 2.05 kg m−2 h−1 under one sun (1 kW m−2) irradiation, with the solar thermal conversion efficiency up to 97.7%. A significantly higher water vapor generation rate of 2.9 kg m−2 h−1 is obtained under one sun irradiation at a wind speed of 2 m s−1. In addition, the evaporator has excellent photothermal antibacterial activity against both E. coli and S. aureus. This bionic evaporator offers a potential low-cost and highly efficient water purification technology that could help mitigate the global water crisis. [Display omitted] • Novel PPy@ALF antibacterial evaporator low vaporization enthalpy was synthesized. • The PPy@ALF evaporator exhibited excellent photothermal evaporation performance. • The microstructural Marangoni convection promotes photothermal evaporation. [ABSTRACT FROM AUTHOR]

• Setting up a closed-water loop for water activation based experiments at JSI, Slovenia. • Considering ITER relevant conditions. • Effective water volume of the activation part is essential parameter for obtaining high activity values along the loop. • A pipe radius of 0.6 cm and a water flow rate range between 0.4 l/s and 0.5 l/s were chosen as the optimal configuration. • Estimated activity values of 16N, 17N and 19O within the radiation part are 1.7·108 Bq, 1.2·104 Bq and 1.4·107 Bq. A closed-water activation loop is being built at the research reactor TRIGA at the Jožef Stefan Institute, Slovenia, which will serve as a well-defined and stable high energy gamma-ray and neutron source. The main focus of this work is to analyse and optimise the main components of the water activation loop to achieve the highest activity at reasonably low pressure drop. Both neutronic and hydraulic aspects were considered. The results show that the desired configuration consists of a high effective water volume of the inner activation part, outer observation part and narrow transport pipes connecting both parts. The complex snail-shape design of the inner part systematically outperformed other simplified designs by more than a factor of two for the main water activated isotopes (16N, 17N and 19O). The activity values increase strongly with increasing flow rate, but reach saturation at about 0.5 l/s. On this basis, the snail configuration was selected as the main candidate for both the inner activation and outer observation part. To not exceed the pressure drop of 3 bar within the closed-water loop, the nominal water flow rate and the inner diameter of the transport pipes were set to 0.5 l/s and 1.2 cm, respectively. [ABSTRACT FROM AUTHOR]

Oxygen vacancy facilitates water activation to create reactive hydroxyl species for the improved low-temperature HCHO oxidation over K+-doped ε-MnO 2. [Display omitted] • Surface oxygen vacancies were regulated with the aid of K doping over ε-MnO 2. • Oxygen vacancies facilitated water activation to produce active hydroxyl species. • The active hydroxyl species and protonated lattice oxygen enhanced the catalytic oxidation activity of HCHO. • The optimized K+-doped ε-MnO 2 exhibited the best catalytic performance for HCHO conversion with a T 90 of 74 °C. H 2 O activation plays a crucial role in the oxidation process of HCHO, which can create active hydroxyl to attack HCHO molecules and enhance the catalytic activity. Therefore, the construction of highly active sites for H 2 O activation to accelerate the reaction rate is required. Herein, we constructed and regulated the surface oxygen vacancies over ε-MnO 2 with the aid of K doping to activate H 2 O through a simple hydrothermal method. The role of oxygen vacancy produced by K+ doping for H 2 O activation in HCHO removal was investigated by various technologies, including XPS, TPD, TPSR, and in-situ DRIFTS. It was found that the addition of K+ not only increased the adsorption sites for negatively charged oxygen atoms of HCHO but also provided oxygen vacancies to induce more active hydroxyl species from water activation. The optimal K+-doped ε-MnO 2 significantly removed 90% of HCHO at 74 °C (GHSV = 120 L/g·h, HCHO = 70 ppm). After the stability test at 65 and 80 °C for 100 h respectively, the conversion did not show a downward trend. This work innovatively developed a K-doped ε-MnO 2 catalyst with surface oxygen vacancy to activate H 2 O and revealed the role of K+ and oxygen vacancy for efficient HCHO oxidation. [ABSTRACT FROM AUTHOR]

Various types of fuel cells as clean and portable power sources show a great attraction, especially direct methanol fuel cell (DMFC) having high energy density, low operating temperature and convenient fuel storage. However, the preparation of low-cost Pt-based catalysts with satisfactory catalytic performance still faces many challenges for its commercialization on large scale. Here, Pt catalysts assisted by carbon quantum dots (CQDs) are reported. The synergistic effect of carbon quantum dots and Pt metals is similar to a bi-component catalyst, such as PtRu. First, carbon quantum dots derived from Vulcan XC-72 carbon black are synthesized by mixed acid etching. Then, carbon black (Vulcan XC-72) is soaked in carbon quantum dots solution for several days to obtain carbon black modified by carbon quantum dots (XC-72-CQDs). Finally, Pt catalysts are supported on XC-72-CQDs (Pt/XC-72-CQDs) through a simple chemical reduction method. For methanol electro-oxidation reaction, the catalytic performance of Pt/XC-72-CQDs is compared with commercial PtRu/C (30% Pt + 15% Ru). Results show that a typical product (Pt/XC-72-CQDs5) exhibits a better catalytic activity than PtRu/C. In cyclic voltammetry test, the specific activity of Pt/XC-72-CQDs5 is 1.06 mA cm −2 Pt and 477.6 mA mg −1 Pt, while that of PtRu/C is 0.77 mA cm −2 Pt and 280.6 mA mg −1 Pt. [ABSTRACT FROM AUTHOR]

[Display omitted] • The 3D rGP aerogel was designed to realize an evaporation rate of 4.89 kg m-2h−1 under 1 sun irradiation. • The ultrahigh evaporation rate of 16.22 kg m-2h−1 by rGP −3 was further achieved under a convective flow of 2.5 m s−1. • The 3D rGP facilitated solar vapor generation by water activation and environmental energy-enhanced effect. • The evaporator reached fully hydrated state quickly and transported water rapidly by introducing superabsorbent PVAP. • The high-throughput evaporative desalination of rGP was obtained by coupling with natural convection. The renewable solar energy provides one of promising pathways of interfacial vapor evaporation for freshwater resources with minimized carbon footprint. The high-throughput evaporation rate needs to be further achieved for the demand of practical application. Herein, a three-dimensional hybrid aerogel (rGP) with reduced graphene oxide (rGO) and polyvinyl alcohol phosphate ester (PVAP) was fabricated by hydrothermal method. The rGP aerogel had broadband light absorption ability and interconnected pore structure. This evaporator achieved fully hydrated state within 5 s due to the superabsorbent PVAP. The existence of intermediate water in rGP reduced the energy requirement for evaporation. The 3D aerogel also harvested additional energy from surroundings caused by evaporation cooling effect. Therefore, the rGP with height of 3 cm (rGP-3) achieved a higher evaporation rate of 4.89 kg m-2h−1 with the energy efficiency of 124.8% under 1 sun irradiation. The vapor diffusion could be assisted by convective flow and minimized the stagnation of vapor in the pores. Then the evaporation rate of rGP-3 increased to 16.22 kg m-2h−1 under the convective flow of 2.5 m s−1. Additionally, the 3D rGP can be consistently evaporated for 8 h in 3.5 wt% brine and no salt deposition occurred. More importantly, the evaporated fresh water from actual seawater was up to 156.30 kg m−2 in 8 h under outdoor sunlight and directional convective flow, which implied the remarkable potential in practical application. This rGP evaporation platform with 3D pore structure, high light absorption, efficient water activation, rapid water transport, extra heat collection, and effective vapor diffusion provides a new inspiration for designing high-throughput evaporators of superhigh evaporation rate and a large-scale application in desalination under convective flow. [ABSTRACT FROM AUTHOR]

A simple, green, novel, time-efficient, and potentially cost-effective water activation method was employed to enhance the electrochemical activity of graphite felt (GF) electrodes for vanadium redox flow batteries (VRFBs). The GF electrode prepared with a water vapor injection time of 5 min at 700 °C exhibits the highest electrochemical activity for the VO 2+ /VO 2 + couple among all the tested electrodes. This is attributed to the small, controlled amount of water vapor that was introduced producing high contents of oxygen-containing functional groups, such as OH groups, on the surface of the GF fibers, which are known to be electrochemically active sites for vanadium redox reactions. Charge–discharge tests further confirm that only 5 min of GF water activation is required to improve the efficiency of the VRFB cell. The average coulombic efficiency, voltage efficiency, and energy efficiency are 95.06%, 87.42%, and 83.10%, respectively, at a current density of 50 mA cm -2 . These voltage and energy efficiencies are determined to be considerably higher than those of VRFB cells assembled using heat-treated GF electrodes without water activation and pristine GF electrodes. [ABSTRACT FROM AUTHOR]

• The interlayer spacing of V 2 O 5 was adjusted through the intercalation of PEDOT. • V 2 O 5 interacts with PEDOT with the phase transition from Quinoid to Benzoid. • A reversible and fast Mg2+ ion storage of V 2 O 5 /PEDOT was achieved. • The enlarged interlayer and water activation improved the kinetic performances. • Bilayer structured V 2 O 5 /PEDOT achieved the high rate and cycling performances. Magnesium ion batteries (MIBs) are attracting attention as promising alternatives to next-generation energy storage systems owing to their high safety, high volumetric capacity, low reduction potential, abundant raw materials, and economic efficiency. However, developing highly reversible and kinetically fast MIB cathode materials is very challenging owing to the sluggish Mg2+ ion diffusion and low reversible capacity typical of bivalent magnesium ions, as well as the strong electrostatic interactions with the host cathode material. Herein, we designed a charge transfer interaction of a bilayered V 2 O 5 /PEDOT (VOP) complex with involving the phase transition of PEDOT from a quinoid to a benzoid structure which could be realized because of reversible and fast Mg2+ ion storage through an enlarged interlayer spacing of 19.02Å. Furthermore, the effect of water activation on the enhancement of the kinetics was confirmed by conducting electrochemical and in-situ/ex-situ characterizations. Consequently, the as-designed VOP electrodes delivered a high specific capacity of 339.7 mAh/g at 100 mA g−1, high-rate capacity of 256.3 mAh/g at 500 mA g−1, and long-term cyclic stability with a 0.065 % decay rate and high capacity of 172.5 mAh/g after 500 cycles. [ABSTRACT FROM AUTHOR]

Pt/In 2 O 3 /Al 2 O 3 catalysts with extremely low Pt loading (1.0 wt%) prepared by incipient-wetness impregnation method were evaluated for methanol steam reforming (MSR) in the temperature range of 200–500 °C, and characterized by means of X-ray diffractions (XRD), high resolution transmission electronic microscopy (HRTEM), Brunauer–Emmett–Teller (BET), CO chemisorption, hydrogen temperature-programmed reduction (H 2 -TPR) and H 2 O temperature-programmed desorption (H 2 O-TPD). Multiple factors including Pt/In 2 O 3 mass ratio, total In 2 O 3 loadings, steam to carbon ratio (S/C) and gas hourly space velocity (GHSV) were found to affect the catalytic properties. Results indicated that indium oxide was homogeneously dispersed on the surface of Al 2 O 3 and also effectively improved the dispersion of Pt nanoparticles. Meanwhile, a good correlation of water activation ability with catalytic selectivity has been established. Accordingly, the synergistic effect caused by the strong Pt–In 2 O 3 interaction and the intimate Pt–In 2 O 3 contact played the crucial role in effective H 2 O activation, thus minimizing the CO selectivity and enhancing the stability of Pt/In 2 O 3 /Al 2 O 3 catalysts because of its high ability to activate H 2 O molecule. As a result, the Pt/In 2 O 3 /Al 2 O 3 catalyst with Pt/In 2 O 3 mass ratio at 1/30 exhibited complete methanol conversion, 99.6% H 2 selectivity and extremely low CO selectivity of 3.2% at 350 °C, outperforming Pt/ZnO/Al 2 O 3 catalyst. Furthermore, Pt/In 2 O 3 /Al 2 O 3 catalyst displayed higher stability than Pt/ZnO/Al 2 O 3 catalyst as evidenced by unnoticeable deactivation under continuous operation for more than 16 h. [ABSTRACT FROM AUTHOR]

The effect of ZnO addition on the dissociation of H 2 O and subsequent effects on cobalt oxidation state and ethanol reaction pathway were investigated over Co/ZrO 2 catalyst during ethanol steam reforming (ESR). Catalyst physical properties were characterized by BET, XRD, and TEM. To characterize the catalysts ability to dissociate H 2 O, Raman spectroscopy, H 2 O-TPO, and pulsed H 2 O oxidation coupled with H 2 -TPR were used. It was found that the addition of ZnO to cobalt supported on ZrO 2 decreased the activity for H 2 O dissociation, leading to a lower degree of cobalt oxidation. The decreased H 2 O dissociation was also found to affect the reaction pathway, evidenced by a shift in liquid product selectivity away from acetone and towards acetaldehyde. [ABSTRACT FROM AUTHOR]

• Water activation. • First Wall CFD models. • Turbulence and stagnation. • Distribution of residence times function. • ANSYS Fluent User Defined Scalars and User Defined Functions. A coupled methodological approach was developed for the modelling of fluid activation on ITER relevant components, using Computational Fluid Dynamics (CFD). Based on ANSYS Fluent's general transport mathematical model, built-in equations (UDS) were customized to represent radioactive species' activation and decay processes, fully embedded in fluid transport equations. Such model, so called Radioactive Species Transport Model (RSTM) was benchmarked against previous approaches on this field. Additionally, two applications relevant for ITER In-Vessel design are reported: (1) a complete FW06 and (2) a complete FW18 with its Shielding Block (SB18). These results provide new sensibility on the effects of flow stagnation and recirculation under real activation rate fields for In-Vessel components. This implementation shows that previous approaches may have overestimated the activation levels expected on downstream FWs by the order of 20–40%, depending on the characteristics of the FW panel. [ABSTRACT FROM AUTHOR]

Solar vapor generation is one of effective techniques in alleviating freshwater shortages. However, targeted gaps of high-efficient solar harvesting and fast evaporation rate still existed. In this work, the polyvinyl alcohol/biochar hydrogels (PBHs) with different water/PVA ratio were fabricated as the effective solar-driven vapor generator. The openly porous structure facilitated the intense capillary effect and water transport to PBH surface. Moreover, the proportion of intermediate water changed with the water/PVA ratio and further reduced the evaporation enthalpy. The solar absorber on the biochar interface confined the convective heat and reduced the heat loss. These properties induced the generation rate of PBH-10 achieving 1.89 kg m−2 h−1 with the solar-to-vapor convection efficiency of 85.2% under 1 sun irradiation. The thermal conduction well fitted to the heat distribution in the evaporation system according to COMSOL simulation. The rate of water vaporization by PBH-10 also maintained excellent performance in the salt rejection and wastewater purification containing different pollutants. It is anticipated that the PBH evaporator provided new possibilities in the clean water collection, desalination, and wastewater purification under natural sunlight. [Display omitted] • PVA skeleton availed water activation and reduced vaporization enthalpy. • Openly porous accelerated water pumping and absorber confined heat in the interface. • The evaporation rate reach 1.89 kg m−2 h−1 with 85.2% energy efficiency under 1 sun. • PHB-10 had excellent capability of desalination and wastewater purification. [ABSTRACT FROM AUTHOR]

Highlights: [•] ZnO addition to Co/C increased COX selectivity for vapor phase ethanol reforming. [•] ZnO facilitated Co oxidation in vapor phase ethanol reforming at 250°C. [•] Metallic Co quickly oxidizes in aqueous phase ethanol reforming regardless of ZnO. [•] ZnO primarily enhanced H2O activation. [•] Cobalt oxidation state is closely related to both support and reaction conditions. [ABSTRACT FROM AUTHOR]

Internal electric field (IEF) at heterojunction interfaces can separate photoexcited charge carriers and promote photocatalytic performance. Here we have modified WO 3 nanoplates with carbon dots (CDs) and constructed an interfacial IEF directing from CDs to WO 3 with assistance of their remarkably different work functions. Such electric field drove photoexcited electrons to transport towards CDs and retained photoexcited holes to stay at WO 3 , achieving electron/hole spatial separation. H 2 O preferred chemisorption on the five-coordinated W atoms of WO 3 with an elongated H-O bond and bent H-O-H angle, which allowed the activation of H 2 O and favorable production of ·OH radicals. The WO 3 /CDs (WC1) showed a superior photocatalytic activity for visible-light photooxidation of HCHO and CH 3 COCH 3 with CO 2 production rate of 411 and 188 μmol g–1 h–1, respectively, outperforming most of WO 3 -based photocatalysts. The enhanced photocatalytic performance correlated with the IEF-induced charge separation, favorable ·OH production and VOCs chemisorption. Our work confirms the role of CDs cocatalyst in the photocatalytic oxidation of VOCs, which will inspire enthusiasm to develop more advanced heterojunction photocatalysts involving carbon nanomaterials. [Display omitted] • Carbon dots-modified WO 3 nanoplates were designed for VOCs photodegradation. • Work function difference enables electron transfer from CDs to WO 3 upon contact. • Internal electric field drives charge separation evidenced by in-situ XPS and DFT simulations. • WO 3 chemisorbs and activates water with preferential hydroxyl radicals production. • Water activation and internal electric field account for superior photocatalytic performance. [ABSTRACT FROM AUTHOR]

Abstract: Photolysis of Mn2(CO)10 in an alkane/water biphasic system has resulted in the generation of 1.80 ± 0.16 mol of hydrogen per mol of Mn2(CO)10. Various studies including deuteration have indeed shown water to be the H2 source while kinetic studies have indicated a strong correlation between the concentration of the key intermediate MnH(CO)5 with the production rate of H2. Some of the oxygen atoms of water have been incorporated into a white solid assigned to MnCO3. A mechanism accounting for MnH(CO)5 formation from Mn2(CO)10 photolysis and subsequently H2 production from MnH(CO)5 has been proposed. [Copyright &y& Elsevier]

Currently, for the EU DEMO, two Breeding Blankets (BBs) have been selected as potential candidates for the integration in the reactor. They are the Water Cooled Lithium Lead and the Helium Cooled Pebble Bed BB concepts. The two BB variants together with the associated ancillary systems drive the design of the overall plant. Therefore, a holistic investigation of integration issues derived by the BB and the installation of its ancillary systems has been performed. The issues related to the water activation due to the 16N and 17N isotopes and the impact on the primary heat transfer systems have been investigated providing guidelines and dedicated solution for the integration of safety devices as isolation valves. The tritium retention and the permeation rates through the blanket and its ancillary systems have been also assessed taking into account different operating points both for the BB and ancillaries and comparing, when possible, the releases with the operating and safety limits. Moreover, the issues related to the tritium start-up inventory as well as the uncertainties on the Tritium Breeding Ratio (TBR) due to the integration of the auxiliary systems within the Vacuum Vessel have been also studied. Finally, the impact of the BB concepts on the safety systems like the Vacuum Vessel Pressure Suppression System is described with a particular focus on the different measures that should be implemented according to the considered concept. All these aspects are then taken into account to drive future developments during the Concept Design Phase. [ABSTRACT FROM AUTHOR]

• In ITER, activated water will generate significant radiation levels during DT pulses. • Currently, this field cannot be reliably modelled due to the cooling system complexity. • Automated geometry modelling and activation calculation methods were developed. • The first realistic neutronics model of the activated water source is presented. During the plasma pulses, the neutron-induced activation of the cooling water will produce an important contribution to the radiation levels in the ITER Tokamak Complex. The resulting radiation field has a complex spatial distribution due to the combination of decay and production of radioisotopes in the intricate cooling lines that feed the numerous systems inside and outside the bio-shield. An accurate estimation of the cooling water radiation field is necessary to ensure that the radiological zoning is respected. As of today, this issue has been studied using simple, manually defined geometries with limited representation of the tens of thousands of components that constitutes the cooling circuits. This work describes the first production of a realistic and up-to-date integral neutronics modelling of all the cooling systems containing activated water beyond the bio-shield. The work was enabled by the development of computerized geometry modelling techniques to automatically simplify and dimension the system components. An independent review of the method ensured the validity of the simplified model. Moreover, automated scripts produced the activated water radiation source associated with the geometry model. The latter was obtained by linking thousands of cylinders, representing the coolant volumes, in chains of MCNP cells that reproduced the paths of the water lines inside the Tokamak Complex and, eventually, by calculating the radioisotopes activity in each cell. This methodology greatly speeds up the modelling time, reduces the risk of human error and enables the representation of the Tokamak Cooling Water System radiation source with an unprecedented degree of realism. [ABSTRACT FROM AUTHOR]

Abstract: The management of activated water in the Large Hadron Collider (LHC) at CERN is a key concern for radiation protection. For this reason, the induced radioactivity of the different water circuits is calculated using the Monte-Carlo (MC) code FLUKA. The results lead to the definition of procedures to be taken into account during the repair and maintenance of the machine, as well as to measures being necessary for a release of water into the environment. In order to assess the validity of the applied methods, a benchmark experiment was carried out at the CERN-EU High Energy Reference Field (CERF) facility, where a hadron beam (120GeV) is impinging on a copper target. Four samples of water, as used at the LHC, and different in their chemical compositions, were irradiated near the copper target. In addition to the tritium activity measured with a liquid scintillation counter, the samples were also analyzed using gamma spectroscopy in order to determine the activity of the gamma emitting isotopes such as and . While for the latter an excellent agreement between simulation and measurement was found, for the calculation of tritium a correction factor is derived to be applied for future LHC calculations in which the activity is calculated by direct scoring of produced nuclei. A simplified geometry representing the LHC Arc sections is then used to evaluate the different calculation methods with FLUKA. By comparing these methods and by taking into account the benchmark results, a strategy for the environmental calculations can be defined. [Copyright &y& Elsevier]

Abstract: A new approach has been proposed for monitoring D–T neutrons in the system using neutron activation of flowing water via the 16O(n,p)16N reaction. The basic idea of the approach is to utilize the Cherenkov light, which is produced by energetic β-particles from 16N in water, in the vicinity of a neutron source and then transmit the light by an optical fiber to the remote light sensor. Further feasibility studies require development of a water Cherenkov detector with an efficient light collection system that satisfies neutron monitoring requirements. Two different designs of the water Cherenkov detector with a fiber readout, as well as results of their irradiation tests are presented in the paper. Designs and the experimental setup are not yet optimized for best performance; obtained detector parameters demonstrate potential capabilities of the proposed approach. [Copyright &y& Elsevier]

The widely accepted mechanism for methanol oxidation on Pt based catalyst surfaces has held that the rate determining step is activation of water, and/or oxidation of surface-bound CO to CO2. In fact on pure Pt, water activation is always rate limiting at potentials negative of 0.6 V. Anode potentials greater than 0.4 V are outside the useful potential window of direct methanol fuel cells when using Nafion 117 at 60 °C. Enhancement of the water activation kinetics on Pt has been effected by the use of oxophilic transition metal promoters including Ru, W and Sn. For decades the search for improved methanol oxidation electrocatalysts has focused on water activation. A systematic deuterium isotope study on Pt black and two active mixed metal catalysts (PtRu and PtRuOsIr) shows that for each catalyst there is a characteristic transition potential above which the primary reaction in the rate-determining step changes from water activation to C&z.sbnd;H bond activation. On the mixed metal catalysts, this crossover potential is ca. 0.35 V, which is within the direct methanol fuel cell potential window (0–0.400 V). This study confirms that on these active catalysts there is a potential above which further improvements in water activation must be concomitant with acceleration of C&z.sbnd;H bond activation. Thus the catalyst search strategy involving Pt promoter metals must also consider the kinetic importance of C&z.sbnd;H bond activation. [Copyright &y& Elsevier]

• The heating load due to water activation and the decay of N-16 produced in the water-based cooling systems has been identified as an important challenge for the ITER design. • A water activation experiment has been proposed at the Joint European Torus (JET), to measure radiation dose and N-16 concentrations in a fusion environment. • We present the preparatory computational and experimental work required for the preparation of the water activation experiment at JET. Fast neutron induced water activation will result in significant additional nuclear heating loads to cryogenic components in the ITER fusion reactor during operation, which are considered as an important issue in the ITER design. A water activation experiment has been proposed at the Joint European Torus (JET) which would enable measurements of radiation dose rates and 16 N concentrations in water, activated in the most representative fusion environment achievable, and extrapolability to ITER conditions. This paper presents a study aimed at establishing the experiment feasibility, in terms of the identification and selection of an experimental location at JET, and the definition of an experimental setup enabling accurate measurements of the quantities of interest. A suitable experimental location in JET was identified in the basement of the JET Torus Hall. The expected 16 O (n , p) 16 N activation rates in the cooling water in the JET tokamak were determined through Monte Carlo particle transport calculations and the induced 16 N activity in the water was propagated to the experimental location. Subsequent calculations were performed to determine the expected detector response to 16 N γ rays for three different JET pulse scenarios. Two scintillator γ detectors were calibrated with standard γ calibration sources and tested with a 244 Cm/ 13 C neutron source, also emitting 6.13 MeV γ rays, corresponding to the 16 N γ ray energy. The presented work demonstrates the feasibility of a water activation experiment at JET and provides valuable information for the experiment design. [ABSTRACT FROM AUTHOR]

Separation performance of nanofiltration (NF) membranes is constrained by the trade-off between permeability and selectivity. Herein, a facile and environmental friendly water activation before microwave heating was performed to improve the performance of NF membranes and overcome this trade-off. The water activation before microwave heating facilitated the hydrolysis of acyl chloride, resulting in a loose polyamide layer with enhanced hydrophilicity and surface charge. The activated NF membrane showed a permeance of 29.9 L m-2 h-1 bar-1, which is almost 2 times higher than the control. The membrane possesses a Na 2 SO 4 rejection of 96.8% and high selectivity to antibiotics and NaCl. At the meantime, the fouling resistance to model foulants including bovine serum albumin and sodium alginate was significantly enhanced. The water activation before microwave heating is proved to be an adequate strategy for fabricating NF membranes. [Display omitted] • A facile water activation before microwave heating was performed to prepare PA NF membranes. • The activated NF membrane showed a 95.9% increment in permeance compared to the control. • The activated NF membrane had good performance in separating antibiotics and NaCl. • The activated NF membrane showed enhanced fouling resistance to BSA and SA. [ABSTRACT FROM AUTHOR]

• Activation of water coming from PHTS of WCLL/HCPB concepts to out-cryostat regions of the DEMO building assessed. • Neutron flux and accumulated dose in silicon calculated for electronics. • Biological dose rate due to ACPs incorporated into the water flow which emit gammas after the shutdown is calculated. • Different configurations of the building shielding materials and components studied. • Benchmark with a similar case on Upper pipe chase. The radiation protection issues linked to the activated cooling water coming from the in-vessel components of a fusion reactor to the ex-vessel regions are important design and safety constraints in the building layout definition, as demonstrated at ITER. To tackle these issues more rigorously already in the pre-conceptual design of DEMO some relevant activation and neutronic studies have been performed for the re-definition of a preliminary architecture of the tokamak complex. The design conditions of the Water Cooled Lithium Lead (WCLL) Breeding Blanket (BB) concept have been considered as well as those of the Helium Cooled Pebble Bed (HCPB). The radiation environment in those areas of the building hosting the pipes carrying activated water devoted to the cooling of the First Wall/limiter and divertor has been characterized in terms of decay photons and secondary neutron emissions, which are emitted by N16 and N17 radionuclides. In particular, the feasibility of placing radiation sensitive equipment near flowing activated water is evaluated by calculating accumulated dose in silicon and neutron flux. Viability for manual maintenance activities is assessed by calculating biological dose rate for workers due to Activated Corrosion Products (ACP). The values achieved are then compared to applicable limits. Identification of problematic areas stimulated the examination of some design proposals to improve shielding materials and components. [ABSTRACT FROM AUTHOR]

Water activated by fast neutrons emits both high energy gammas from 16N and delayed neutrons from 17N. The radioisotopes 16,17 N are produced through the 16O(n,p)16N and 17O(n,p)17N reactions (thresholds about 10 MeV) and decay through the reactions 16N ( T 1∕2 = 7. 13 ± 2 s) → 16 O + γ (67% @ 6.13 MeV, 5% @ 7.12 MeV) and 17N ( T 1∕2 = 4. 173 ± 4 s) → 17 O → 16 O + n (37.7% @ 0.386 MeV, 0.6% @ 0.886 MeV, 49.8% @ 1.16 MeV, 6.9% @ 1.69 MeV), γ (3.7% @ 0.87 MeV), respectively. Activated water, flowing throughout a nuclear plant distributes the radioactivity to many critical components where personnel and/or instrumentation can be located thus depositing additional radiation dose which requires a proper shielding. This source of radiation represents an issue for a D-T fusion device like ITER which uses water as the main cooling fluid for components such as e.g. first wall and divertor. Owing to the scarce experimental information available for the cross sections of the 16O(n,p)16N and 17O(n,p)17N reactions and few benchmark validations, large uncertainties are affecting the calculations of the water activation induced by DT neutrons in a tokamak. In the attempt to improve the available nuclear data Fusion for Energy (F4E) tasked ENEA to carry on a benchmark experiment to validate the water activation calculations presently performed for ITER. This benchmark experiment was carried out in the year 2019 irradiating with the 14 MeV neutrons produced by the Frascati Neutron generator (FNG) a small size ITER First Wall mock-up. Demineralized water was circulating inside the mock-up and downstream of the irradiation zone the 16N gamma-rays decay and the 17N neutrons decay were measured using proper detectors. The experiment was simulated using the MCNP and the FISPACT codes. The obtained C/E values are in a range close to unit for both 16,17 N isotopes. However, due to the large uncertainty on the 16O(n,p)16N and 17O(n,p)17N reactions cross-sections, for some of the used cross-section data base, e.g. ENDF/B-VIII.0, the C/E is affected by large uncertainty. This is especially true for the case of 17N which production cross-section is affected by ± 60% uncertainty. In the attempt to measure and validate the cross-section data for 16,17 N production, the water activation experiment was repeated at FNG so to measure directly the 16,17 O(n,p) 16,17 N reaction cross-sections at almost monochromatic energies. The results of this new experiment are presented in this paper and compared to the data currently used by ITER project for calculating the water activation. [ABSTRACT FROM AUTHOR]

• Water activated by 14 MeV neutrons emits both high energy gammas from 16N and delayed neutrons from 17N. • These sources of radiation represent one of the main issues for ITER, need to validate the calculation methodology for ITER. • An experiment was commissioned by F4E to ENEA. • 6.73 MeV gamma-rays from 16N and neutrons from 17N were measured by CsI g-detector and an array of 3He counters, respectively. • Calculation performed using MCNP code coupled to the FENDL3.1 data library and the EASY-2007 inventory code. • The C/E ratio is close to unity, it is affected by an error > ±60% to be ascribed nuclear data used for calculation. Water activated by 14 MeV neutrons emits both high energy gammas from 16N and delayed neutrons from 17N. The isotopes 16,17N are produced through the 16O(n,p)16N (T 1/2 = 7.13 s) and 17O(n,p)17N (T 1/2 = 4.1 s) reactions, respectively. These sources of radiation represent one of the main issues for ITER having large impact on the design of the machine and on the qualification of components. To validate the calculation methodology used for ITER and to reduce the safety factors applied to the calculation results a water activation experiment was commissioned by F4E to ENEA and performed at the 14 MeV Frascati neutron generator (FNG). The experimental set-up consisted of a closed water loop, about 40 m long, where the cooling water, while transiting through an ITER FW mock-up, was irradiated by the D-T neutrons produced at FNG. 6.73 MeV gamma-rays from 16N and delayed (fast) neutrons from 17N were measured using a large CsI gamma-ray detector and an array of absolutely calibrated 3He detectors, respectively. This paper reports on the measurements of the delayed neutrons emission from 17N. The calibration of the 3He detector array and the experimental set-up are first discussed. Then the experimental results (E) for the delayed neutrons as well as the comparison with the calculation (C) performed using the MCNP Monte Carlo code (coupled to the FENDL3.1 data library) and the EASY-2007 inventory code are presented. The C/E ratio results close to unity, however it is affected by a very large error (> ±60 %) to be ascribed mainly to the uncertainty on the nuclear data used for calculation. [ABSTRACT FROM AUTHOR]