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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]

In ITER, the evaluation of the activated water radiation source and its impact on the radiological levels is necessary to demonstrate compliance with the safety requirements. The use of simplified or conservative approaches often results in the application of expensive constraints on the installation that impact its economics, operations, and construction schedule. In this work, we propose a novel methodology to calculate the activated water source term with a higher degree of realism. The methodology is based on the coupling of a system-level code with a Computational Fluid Dynamics (CFD) code in an explicit, one-way approach. We apply this methodology to the evaluation of the 16N radioisotope within the ITER Vacuum Vessel Primary Heat Transfer System (VV-PHTS) cooling circuit in a steady-state and transient scenarios. We chose this system since previous analyses of the VV-PHTS were done with simple, ad-hoc calculations that yielded results that differed by up to a factor of five, underscoring a higher level of uncertainty. As a result, we generate a computational model of the source term that can be used to evaluate the radiological condition surrounding the cooling systems during the operations.

Insufficient determination of the effect of surface-active substances introduced in extremely low concentrations on the formation of the stability of the properties of fine-grained concrete based on composite Portland cements determined the feasibility of conducting research in this area. The studies investigated the influence of the modification of composite cement with water activated by the use of the hydrophilic hydration mechanism. It has been proven that these factors include the type and amount of applied water nano modifiers. The analysis of the study results confirmed that the introduction of water activated by the mechanism of hydrophilic hydration into concrete in extremely small doses significantly increases the rate of formation of concrete strength and reduces the coefficient of its variation. Owing to this, the strength of the resulting modified fine-grained concrete based on composite cement at the age of 3 days exceeds the strength of the similar concrete without additives by 300 %, and at the age of 27 days – by 25 %. At the same time, the coefficient of variation of strength has a minimum value at the optimal amount of nano additive – water modifier. This allows us to assert the effectiveness of the revealed mechanism of modification of composite cement. Thus, there are reasons to assert the possibility of targeted regulation of the processes of formation of a strong homogeneous structure of fine-grained concrete based on composite cement by using water activated by the mechanism of hydrophilic hydration. [ABSTRACT FROM AUTHOR]

High‐performance catalysts sufficient to significantly reduce the energy barrier of water activation are crucial in facilitating reactions that are restricted by water dissociation. Herein we present a Cu−Co double‐atom catalyst (CuCo‐DAC), which possesses a uniform and well‐defined CuCoN6(OH) structure, and works together to promote water activation in silane oxidation. The catalyst achieves superior catalytic performance far exceeding that of single‐atom catalysts (SACs). Various functional silanes are converted into silanols with up to 98 % yield and 99 % selectivity. Kinetic studies show that the activation energy of silane oxidation by CuCo‐DAC is significantly lower than that of Cu single‐atom catalyst (Cu‐SAC) and Co single‐atom catalyst (Co‐SAC). Theoretical calculations demonstrate two different reaction pathways where water splitting is the rate‐determining step and it is accelerated by CuCo‐DAC, whereas H2 formation is key for its single‐atom counterpart. [ABSTRACT FROM AUTHOR]

Catalytic ozone (O3) decomposition at high relative humidity (RH) remains a great challenge due to the catalysts poison and deactivation under high humidity. Here, we firstly elaborate the role of water activation and the corresponding mechanism of the promoted O3 decomposition over the three‐dimensional monolithic molybdenum oxide/graphdiyne (MoO3/GDY) catalyst. The O3 decomposition over MoO3/GDY reaches up to 100 % under high humid condition (75 % RH) at room temperature, which is 4.0 times as high as that of dry conditions, significantly surpasses other carbon‐based MoO3 materials(≤7.1 %). The sp‐hybridized carbon in GDY donates electrons to MoO3 along the C−O−Mo bond, facilitating water activation to form hydroxyl species. As a result, hydroxyl species dissociated from water act as new active sites, promoting the adsorption of O3 and the generation of new intermediate species (hydroxyl ⋅OH and superoxo ⋅O2−), which significantly lowers the energy barriers of O3 decomposition (0.57 eV lower than dry conditions). [ABSTRACT FROM AUTHOR]

The object of research is fine-grained concrete on slag Portland cement. Owing to the significant content of metallurgical industry waste in its composition, slag Portland cement belongs to ecologically acceptable products. However, the insufficient rate of formation of its structure and, as a result, the main quality indicator, which is compressive strength, limits the field of use of slag Portland cement. Therefore, in the studies, the goal was to increase the speed of formation of the strength of fine-grained concrete made on slag Portland cement. The studies of the influence of modification of slag Portland cement with water, activated by the use of the hydrophobic hydration mechanism, established the factors affecting the speed of formation and the value of compressive strength of fine-grained concrete made on slag Portland cement. It has been proven that these factors include the type and amount of applied water nanomodifiers, as well as the type and amount of fine concrete aggregate. The analysis of the study results confirmed that the introduction of water activated by the mechanism of hydrophobic hydration into concrete in ultra-small doses significantly increases the rate of formation of concrete strength. Given this, the strength of the resulting modified fine-grained concrete based on slag Portland cement at the age of 2 days exceeds the strength of the similar concrete without additives by 60 %, and at the age of 210 days – by 25 %. This allows us to assert the effectiveness of the identified mechanism of modification of slag Portland cement. Thus, there are reasons to assert the possibility of targeted regulation of the processes of forming a strong structure of fine-grained concrete based on slag Portland cement by using water activated by the mechanism of hydrophobic hydration. [ABSTRACT FROM AUTHOR]

The hydride ion transfer and proton transfer are the key steps in the reactions of (de)hydrogenation, dehydrocoupling, production of H2, and reduction of CO2 with the participation of transition metal hydrides; complexes with bifunctional ligands often act as catalysts for these transformations. The aim of this work was to study the hydride-donating properties of pincer palladium(II) hydride (PNP)PdH (1; PNP is bis(2-diisopropylphosphino-4-methylphenyl)amide). For this purpose, its reaction with Lewis acids (BF3·Et2O, B(C6F5)3) was studied using IR and NMR spectroscopies combined with quantum chemical calculations (DFT/M06/def2-TZVP). Correlations between electrochemical reduction potentials of the corresponding cations and thermodynamic hydridity of the metal hydrides proposed in the literature were also applied. [(PNP)Pd(MeCN)][BF4] undergoes an irreversible two-electron reduction in acetonitrile ( = –1.82 V). The use of the obtained potential in correlations gives an overestimated value of the hydride donating ability It was found that the reaction of 1 with boron-containing Lewis acids unexpectedly leads to the protonation of the nitrogen atom of the pincer ligand with an impurity of water, rather than the reaction with the hydride ligand. According to DFT calculations, the proton affinity of the nitrogen atom is much higher than that of PdH, which determines its higher activity in protonation processes. [ABSTRACT FROM AUTHOR]

The steric tuning of a tridentate acridane‐derived NNN pincer ligand allows for the isolation of a strictly T‐shaped phosphine that exhibits ambiphilic reactivity. Well‐defined phosphorus‐centered reactivity towards nucleophiles and electrophiles is reported, contrasting with prior reports on this class of compounds. Reactions towards oxidants are also described. The latter result in the two‐electron oxidation of the phosphorus atom from +III to +V and are accompanied by a strong geometric distortion of the NNN pincer ligand. By contrast, cooperative activation of E−H (HCl, HBcat, HOMe) bonds proceeds with retention of the phosphorus redox state. When using H2O as a substrate, the reaction results in the full disassembly of H2O to its constituent atoms, highlighting the potential of this platform for small molecule activation reactions. [ABSTRACT FROM AUTHOR]

Bioadhesives comprising of catechol crosslinkers have displayed broad utility against both soft and hard substrates. However, catechol's two-part adhesion chemistry requires oxidative chemicals that are detrimental to organic substrates. Herein, a water-activated adhesive with inherent antibacterial properties is prepared by grafting catechol groups onto branched polyethylenimine (PEI-DBA20). The resultant PEI-DBA20 is stable in organic solvents but undergoes curing in the presence of water. The in-built oxidation method relies on the close proximity of catechol/Schiff base functional groups that form tautomers in the presence of aqueous solvents. The curing mechanism is demonstrated by dip coating hydrated substrates, where the grafted dendrimers subsequently crosslink and form thin films. Coated PET films and polyester textiles exhibit an antimicrobial surface with 4–6 log reduction against model Gram-negative bacteria.

Solar-driven interfacial evaporation (SDIE) is emerging as a promising pathway to solving the worldwide water shortage and water pollution. Nanomaterials (e.g., plasmonic metals, inorganic/organic semiconductors, and carbon nanomaterials) and related nanochemistry have attracted increasing attention for the solar-to-vapor process in terms of broadband absorption, electronic structure adjustment, and surface/interface chemistry manipulation. Furthermore, the assembly of nanomaterials can contribute to the mass transfer, heat management, and enthalpy regulation of water during solar evaporation. To date, numerous nano-enabled materials and structures have been developed to improve the solar absorption, heat management (i.e., heat confinement and heat transfer), and water management (i.e., activation, evaporation, and replenishment). In this review, we focus on a systematical summary about the composition and structure engineering of nanomaterials in SDIE, including size and morphology effects, nanostructure optimizations, and structure-property relationship decoupling. This review also surveys recent advances in nanochemistry (e.g., preparation chemistry and structural chemistry) deployed to conceptual design of nanomaterials. Finally, the key challenges and future perspectives of nanomaterials for solar evaporation are overviewed. This review aims at providing guidance for the design and construction of nanomaterials for high-efficiency SDIE on the basis of the aspects of materials science and chemical engineering. [ABSTRACT FROM AUTHOR]

Solar interfacial vapor generation based on low evaporation energy requirements is an effective technology to speed up water purification under natural sunlight, offering great potential to alleviate the current global water crisis. The external electric field and hydrogel are two independent methods enabling low‐energy water evaporation. However, the complicated external equipment for generating an electric field and the restricted activation area of hydrogels significantly limit their practical application in steam generation. Thus, a piezoelectric fiber membrane is embedded into a highly hydratable light‐absorbing poly(vinyl alcohol) (PVA) hydrogel for synergistic water activation. The integrated evaporator is capable of continuously converting the wave energy reserved in the ocean into electrical energy, activating the water in the hydrogel. It is found that the activation effect leads to an improvement of over 23% compared to a non‐piezoelectric hydrogel evaporator. This work provides an evaporation prototype based on the synergistic water activation of wave‐triggered electricity and highly hydratable hydrogel. [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]

Abstract Solar interfacial vapor generation based on low evaporation energy requirements is an effective technology to speed up water purification under natural sunlight, offering great potential to alleviate the current global water crisis. The external electric field and hydrogel are two independent methods enabling low‐energy water evaporation. However, the complicated external equipment for generating an electric field and the restricted activation area of hydrogels significantly limit their practical application in steam generation. Thus, a piezoelectric fiber membrane is embedded into a highly hydratable light‐absorbing poly(vinyl alcohol) (PVA) hydrogel for synergistic water activation. The integrated evaporator is capable of continuously converting the wave energy reserved in the ocean into electrical energy, activating the water in the hydrogel. It is found that the activation effect leads to an improvement of over 23% compared to a non‐piezoelectric hydrogel evaporator. This work provides an evaporation prototype based on the synergistic water activation of wave‐triggered electricity and highly hydratable hydrogel.

Here, noble‐metal‐doped two‐dimensional metal oxide nanosheets are designed to realize selective CO2 photoreduction to CH4. As a prototype, Pd‐doped CeO2 nanosheets are fabricated, where the active sites of Pdδ+ (2<δ<4) and Ce3+−Ov are revealed by quasi in situ X‐ray photoelectron spectra and in situ electron paramagnetic resonance spectra. Moreover, in situ Fourier‐transform infrared spectra of D2O photodissociation and desorption verify the existence of the Pd−OD bond, implying that Pdδ+ sites can participate in water oxidation to deliver H* species for facilitating the protonation of the intermediates. Furthermore, theoretical calculations suggest the Pd doping could regulate the formation energy barrier of the key intermediates CO* and CH3O*, thus making CO2 reduction to CH4 become the favorable process. Accordingly, Pd‐doped CeO2 nanosheets achieve nearly 100 % CH4 selectivity of CO2 photoreduction, with the raising CH4 evolution rate of 41.6 μmol g−1 h−1. [ABSTRACT FROM AUTHOR]

The sluggish kinetics of hydrogen evolution reaction (HER) via water reduction limits the efficiency of alkaline water electrolysis. The HER kinetics is not only intimately related to the catalyst surface structure but also relevant to the cation identity of the electrolyte. The cation dependence also relies on the surface electronic structure and applied potential, but this interrelated effect and its underlying mechanism awaits elucidation. Herein, differently-charged molybdenum sulfide (MoS x ) cluster supports ([Mo 3 S 13 ] 2- and [Mo 3 S 7 ] 4+ ) are utilized to hybridize with the identical metallic Ru centers. The specific electrostatic interaction between MoS x clusters and Ru precursors induces different Ru valences of the hybrids, with a higher valence state for Ru/Mo 3 S 13 endowing a higher activity. The Ru/Mo 3 S 13 and Ru/Mo 3 S 7 exhibited drastically-different cation dependence, in which the charged support determines the local accumulation of cations and resulting water structures. The more negatively-charged Mo 3 S 13 support induces the facile accumulation of cations, especially for less-hydrated K + cations. The water activation capability by Ru valences and cation accumulation from the support effect in-together determine the cation-dependent alkaline HER activity. This work not only enriches the understanding about the cation-dependent HER mechanism but also shines a light on the rational optimization strategy of electrode/electrolyte interfaces., (© 2024 Wiley‐VCH GmbH.)

In adhesive industry, tapes are renowned for their superior flexibility, repeatability, and ease of storage compared to glues. However, conventional adhesive tapes often suffer from low adhesion strength (<500 kPa). This work introduces an innovative adhesive tape composed of an amphiphilic copolymer and a hydrophobic ionic liquid, achieving an ultrahigh adhesion strength of up to 3.1 MPa on various substrates, making a record-high strength to date for tape-type adhesives. This exceptional adhesion performance is facilitated by water droplets applied at the bonding interface, transforming the adhesive surface into a glue-like property without the need for curing treatments or additional auxiliary equipment. By combining the advantageous features of both glues and tapes, these adhesives are termed as transient semi-glue tapes (TSGT). The mechanism behind such water activation and self-locking process is elucidated, and a general preparation approach is developed. Furthermore, the repeatability and recyclability of TSGT are demonstrated, offering an ingenious solution to this long-standing engineering challenge., (© 2024 Wiley‐VCH GmbH.)

Interfacial solar vapor generation is an emerging technology that has the potential to alleviate the current global water crisis. However, water evaporation is an energy‐intensive phase‐change process and thus suffers from an inherently low evaporation yield. New stable and environmentally tolerant materials that can reduce energy requirements and accelerate water evaporation stand out from various studies. In this contribution, a piezoelectric ultrathin nanofilm is integrated into a solar evaporation membrane for simultaneous power generation and water activation. The resulting evaporator is used to continuously convert the wave energy in the ocean into electrical energy. It is found that the electrical energy generated by the evaporator can activate water in adjacent regions, facilitating water evaporation with an additional improvement of over 20% compared to an equivalent non‐piezoelectric evaporator. This paper presents the innovation of a promising membrane evaporation prototype based on the integration of wave‐triggered electricity and water activation. [ABSTRACT FROM AUTHOR]

Ammonia borane (AB) is regarded as a promising chemical hydrogen-storage material due to its high hydrogen content, non-toxicity, and long-term stability under ambient temperature. However, constructing advanced catalysts to further promote the hydrogen production still remains a challenge for the hydrolysis of AB. Herein, we report a novel oxygen modified CoP2 (O-CoP2) material with dispersed palladium nanoparticles (Pd NPs) as a highly efficient and sustainable catalyst for AB hydrolysis. The modification of oxygen could optimize the catalytic synergy effect between CoP2 and Pd NPs, achieving enhanced catalytic activity with a turnover frequency (TOF) number of 532 min−1 and an activation energy (Ea) value of 16.79 kJ·mol−1. Meanwhile, reaction kinetic experiments prove that the activation of water is the rate-determining step (RDS). The water activation mechanism is revealed by quasi in-situ X-ray photoelectron spectroscopy (XPS) and in-situ X-ray absorption fine structure (XAFS) measurements. The activation of water leads to the production of -H and -OH groups, which are further adsorbed on the oxygen atoms in P-O bond and Pd atoms, respectively. In addition, density functional theory (DFT) calculations indicate that the introduced oxygen facilitates the adsorption and activation of water molecules. This novel modulation strategy successfully sheds new light on the development of advanced catalysts for hydrolysis of AB and beyond. [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]

NiFe layered double hydroxides (NiFe-LDH) exhibited an outstanding performance and promising application potential for removing ozone. However, the effect of interlayer anions on ozone removal remains ambiguous. Here, a series of NiFe-LDH with different interlayer anions (F - , Cl - , Br - , NO 3 - , CO 3 2- , and SO 4 2- ) were prepared to investigate the effect of the interlayer anion on ozone removal for the first time. It was found that the interlayer anions are a key factor affecting the water resistance of the NiFe-LDH catalyst under moist conditions. NiFe-LDH-CO 3 2- exhibited the best water resistance, which was much better than that of NiFe-LDH containing other interlayer anions. The in situ DIRFTS demonstrates that the carbonates in the interlayer of NiFe-LDH-CO 3 2- will undergo coordination changes through the interaction with water molecules under moist conditions, exposing new metal sites. As a result, the newly exposed metal sites could activate water molecules into hydroxyl groups that act as active sites for catalyzing ozone decomposition. This work provides a new insight into the interlayer anions of LDH, which is important for the design and development of LDH catalysts with excellent ozone removal properties.

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]

Dried (nonactivated) and water-soaked (activated) pecan shells were pyrolyzed at 450°C for 1 h. The pecan shells were heated in a reduced oxygen environment and cooled under positive pressure of nitrogen. Batch sorption experiments were done to evaluate the biochar's ability to adsorb lead from aqueous solution. Several characterization analyses were performed including FT-IR, elemental analysis, SEM, EDX, and BET. Nonactivated pecan shell biochar (NPSB) has an adsorption capacity of 36.5 mg/g and the water-activated pecan shell biochar (WPSB) adsorbs 61% more lead with a capacity of 58.6 mg/g. The yield of the WPSB is marginally higher than NPSB (34.8% and 33.7%, respectively); however, there are significant differences in the surface morphology. NPSB has a total surface area of 25.48 m2/g. Of this, 29.74% is micropore volume. After water activation, WPSB's total surface area increases to 41.51 m2/g and the micropore volume was significantly reduced. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) are among the most studied and promising materials for selective CO2 capture and transformation. The high CO2 sorption capacity associated with the possibility to activate this rather stable molecule through stabilization of ionic/radical species or covalent interactions either with the cation or anion has opened new avenues for CO2 functionalization. However, recent reports have demonstrated that another simpler and plausible pathway is also involved in the sorption/activation of CO2 by ILs associated with basic anions. Bare ILs or IL solutions contain almost invariable significant amounts of water and through interaction with CO2 generate carbonates/bicarbonates rather than carbamic acids or amidates. In these cases, the IL acts as a base and not a nucleophile and yields buffer‐like solutions that can be used to shift the equilibrium toward acid products in different CO2 reutilization reactions. In this Minireview, the emergence of IL buffer‐like solutions as a new reactivity paradigm in CO2 capture and activation is described and analyzed critically, mainly through the evaluation of NMR data. [ABSTRACT FROM AUTHOR]

Mesoporous copper–titanium dioxide (Cu/TiO2) composite aerogels with <5-nm-diameter copper (Cu) nanoparticles hydrolyze the chemical warfare (CW) simulant dimethyl methylphosphonate (DMMP) under aerobic and anaerobic conditions. After Cu/TiO2 is exposed to DMMP in an in situ diffuse-reflectance infrared Fourier transform spectroscopy (DRIFTS) reaction chamber, hydrolysis products (i.e., methoxy groups) are bound to the surface, while no intact DMMP is observed. In contrast, DMMP degradation is not observed under our DRIFTS reactor conditions at native TiO2 aerogels, CuO, or Cu2O nanoparticles. We attribute the hydrolytic activity of Cu/TiO2 aerogels to a high surface concentration of OH species that form at Cu||TiO2 junctions. Neither hydrolysis of DMMP nor excess surface OH is observed on Au/TiO2 aerogels. The poor ability of the Au||TiO2 interface to activate water relative to that of the Cu||TiO2 interface suggests that a readily reducible supporting oxide is insufficient to promote an excess population of surface OH speciesthe supported nanoparticle must be sufficiently redox-active as well. Under aerobic conditions, DMMP hydrolysis is accelerated on Cu/TiO2, suggesting that O2 promotes the formation and turnover of surface OH sites. The general materials design demonstrated here of a Cu nanoparticle/reducing oxide aerogel is a promising route to CW decontamination as well other surface-mediated chemistries requiring the activation of water. [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]

Surface modification of titania surfaces with dispersed metal oxide nanoclusters has the potential to enhance photocatalytic activity. These modifications can induce visible light absorption and suppress charge carrier recombination which are vital in improving the efficiency. We have studied heterostructures of Mn4O6 nanoclusters modifying the TiO2 rutile (110) and anatase (101) surfaces using density functional theory (DFT) corrected for on-site Coulomb interactions (DFT + U). Such studies typically focus on the pristine surface, free of the point defects and surface hydroxyls present in real surfaces. In our study we have considered partial hydroxylation of the rutile and anatase surfaces and the role of cation reduction, via oxygen vacancy formation, and how this impacts on a variety of properties governing the photocatalytic performance such as nanocluster adsorption, light absorption, charge separation, and reducibility. Our results indicate that the modifiers adsorb strongly at the surface and that modification extends light absorption into the visible range. MnOx-modified titania can show an off-stoichiometric ground state, through oxygen vacancy formation and cation reduction spontaneously, and both modified rutile and anatase are highly reducible with moderate energy costs. Manganese ions are therefore present in a mixture of oxidation states. Photoexcited electrons and holes localize at cluster metal and oxygen sites, respectively. The interaction of water at the modified surfaces depends on the stoichiometry and spontaneous dissociation to surface bound hydroxyls is favored in the presence of oxygen vacancies and reduced metal cations. Comparisons with bare TiO2 and other TiO2-based photocatalyst materials are presented throughout.

Solar-powered vapor evaporation (SVG), based on the liquid-gas phase conversion concept using solar energy, has been given close attention as a promising technology to address the global water shortage. At molecular level, water molecules escaping from liquid water should overcome the attraction of the molecules on the liquid surface layer to evaporate. For this reason, it is better to reduce the energy required for evaporation by breaking a smaller number of hydrogen bonds or forming weak hydrogen bonds to ensure efficient and convenient vapor production. Many novel evaporator materials and effective water activation strategies have been proposed to stimulate rapid steam production and surpass the theoretical thermal limit. However, an in-depth understanding of the phase/enthalpy change process of water evaporation is unclear. In this review, a summary of theoretical analyses of vaporization enthalpy, general calculations, and characterization methods is provided. Various water activation mechanisms are also outlined to reduce evaporation enthalpy in evaporators. Moreover, unsolved issues associated with water activation are critically discussed to provide a direction for future research. Meanwhile, significant pioneering developments made in SVG are highlighted, hoping to provide a relatively entire chain for more scholars who are just stepping into this field., (© 2023 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

The paper considers the mechanism of reactions that lead to a change in the physicochemical properties of water in the case of its electrochemical activation with non-equilibrium plasma. The uniqueness of the method of the low-temperature plasma electrolysis (LTPE) consists in the fact that one electrode is placed in the liquid phase while the other is placed at some distance from the surface of the liquid, which offers new possibilities for the electrochemical method. It is shown that in the LTPE treatment of water, some destructive changes occur, which can result in the formation of peroxide and superoxide compounds with high oxidation properties. It is supposed that the mechanism of these processes is based on the appearance and functioning of a bipolar electrode at the liquid–gas interface. [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]

The reaction of [V(PS3")]− (1) (PS3"=[P(C6H3‐3‐Me3Si‐2‐S)3]3−) with H2O led to the formation of [VIV(PS3")(PS2"SH)]− (2) (PS2"SH=[P(C6H3‐3‐Me3Si‐2‐S)2(C6H3‐3‐Me3Si‐2‐SH)]2−), indicating a hydrogen atom transfer from H2O to a bound thiolate in 1. Furthermore, the reaction of 1 with CH3OH gave the generation of complexes 2 and 3, [VIV(PS3")(PS2"SCH3)]− (PS2"SCH3=[P(C6H3‐3‐Me3Si‐2‐S)2(C6H3‐3‐Me3Si‐2‐SCH3)]2−), implying that C−O and O−H bonds are cleaved by 1. Quantum mechanical calculations were performed to provide the mechanistic understanding for the reactivity of 1 with water. A key transition state with a lower kinetic barrier is identified. It involves an O−H bond cleavage by a dissociated thiyl radical with an interaction between an OH group and a neighboring bound sulfur donor. To our knowledge, the reactivity of 1 represents a new mode for water activation conducted through cooperation between a metal‐stabilized thiyl radical and a neighboring thiolato donor. A metal‐bound thiyl radical is capable of activating H2O and CH3OH through the homolytic cleavage of O−H and C−O bonds, leading to the formation of thiol and methyl thioether. The system also represents a new type of transformation for water activation conducted through cooperation between a metal‐stabilized thiyl radical and a neighboring thiolato donor. [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]

The authors considered device and basic principles of technological line operation for complex fertilizers production on a basis of the humic ones. Its technical characteristics, analysis of the received product are given. Relevance of humic fertilizers application in the conditions of modern agriculture is opened. The most perspective of inexpensive organo-mineral fertilizers are humic (humates) and the complex fertilizers created on basis of them. Main active ingredient of such fertilizers are humic and fulvic acids. Humates, making a humus basis, influence structure of the soil well, increasing gas permeability and moisture content, reduce a soil erosion that in many respects determines its yielding potential and fertility. Their application promotes ecological improvement and a detoxication of the polluted lands, recultivation and restoration of the exhausted and infected lands. Humates absorptive radionuclides which are in the soil, pesticides, toxic substances and heavy metals in the insoluble and not acquired by plants connections and therefore provide ecological purity of production. We still have not in Russia industrial production of the specialized equipment for preparation of humic fertilizers from peat. Enterprises have to adapt for these purposes different types of processing equipment borrowed from other industries. However such equipment does not provide a necessary technological mode and reduces quality of fertilizers.

A conventional Pt/CeO2/Al2O3 catalyst physically mixed with an ionic conductor (Mo- or Eu-doped ZrO2) was tested at high space velocity (20,000 h−1 and 80 L h−1 gcat−1) under model conditions (only with CO and H2O) and industrial conditions, with a realistic feed. The promoted system with the ionic conductor physically mixed showed better catalytic activity associated with better water dissociation and mobility, considered as a rate-determining step. The water activation was assessed by operando diffuse reflectance infrared fourier transformed spectroscopy (DRIFTS) studies under reaction conditions and the Mo-containing ionic conductor exhibited the presence of both dissociated (3724 cm−1) and physisorbed (5239 cm−1) water on the Eu-doped ZrO2 solid solution, which supports the appearance of proton conductivity by Grotthuss mechanism. Moreover, the band at 3633 cm−1 ascribed to hydrated Mo oxide, which increases with the temperature, explains the increase of catalytic activity when the physical mixture was used in a water gas shift (WGS) reaction.

Catalytic ozone (O 3 ) decomposition at high relative humidity (RH) remains a great challenge due to the catalysts poison and deactivation under high humidity. Here, we firstly elaborate the role of water activation and the corresponding mechanism of the promoted O 3 decomposition over the three-dimensional monolithic molybdenum oxide/graphdiyne (MoO 3 /GDY) catalyst. The O 3 decomposition over MoO 3 /GDY reaches up to 100 % under high humid condition (75 % RH) at room temperature, which is 4.0 times as high as that of dry conditions, significantly surpasses other carbon-based MoO 3 materials(≤7.1 %). The sp-hybridized carbon in GDY donates electrons to MoO 3 along the C-O-Mo bond, facilitating water activation to form hydroxyl species. As a result, hydroxyl species dissociated from water act as new active sites, promoting the adsorption of O 3 and the generation of new intermediate species (hydroxyl ⋅OH and superoxo ⋅O 2 - ), which significantly lowers the energy barriers of O 3 decomposition (0.57 eV lower than dry conditions)., (© 2023 Wiley-VCH GmbH.)

Recent advances in single atom catalysis have sparked interest in their use as low-cost and high-efficiency catalysts in a wide variety of reactions. One such reaction that has been heavily studied with single atom catalysts is the water gas shift reaction. In addition, water participates in a rich variety of other industrially important catalytic processes, such as steam reforming reactions. However, much debate surrounds the structure and activity of single atoms toward water gas shift chemistry. By taking a model study approach, we determine the influence of atomically dispersed Pt atoms on the activation of water. Using a thin film Cu 2 O/Cu(1 1 1) support, water activation is probed via isotopic scrambling temperature programed desorption experiments. We determine that the presence of supported single Pt atoms on the thin Cu 2 O film will facilitate the low-temperature activation of water. Theory offers a viable water scrambling pathway on the supported Pt atoms, detailing the dynamic relationship between water, the Pt atom, and the support. The results reveal that single Pt atoms are capable of O-H bond activation when water interacts with such a catalyst. [ABSTRACT FROM AUTHOR]

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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]

Unusual spectrographic signatures can be induced into water by radiant non-contact material-environmental influences. Farultraviolet (UV) absorption and near-UV/ blue fluorescence properties were observed to appear in distilled water samples by charging inside the controversial Wilhelm Reich Orgone Accumulator (ORAC), where no chemical or material contacts were made between the charging ORAC device and the water being treated. Similar spectral absorbance and fluorescence reactions were identified in natural rainwater and snowmelt samples, being nearly identical in spectral properties to the ORAC-charged water samples. Spectral similarities, as found in other studies of water structure or activation -- such as exclusion-zone (EZ) water samples, and in aqueous solutions of DNA -- have also been identified. These repeating spectral absorbance and fluorescence similarities as found in such diverse experimental or natural influences, involving both direct physical contact and non-contact radiant induction, are postulated to indicate a substantive cosmic energy which infuses into favorably-exposed water. Widely-observed natural optical phenomena of a similar blue color, almost uniformly detected by spectral intensity measures suggestive of water-structure fluorescence reactions, but rarely considered as such, are also discussed. Examples include certain exceptionally blue mountain lakes, blue glowing atmospheres over certain mountain ranges, blue-glowing waters and hot springs with healing properties, and blue glacial ice blocks and snow holes, as observed under both direct sunlight and overcast conditions. Certain blue-glowing astrophysical phenomena are also considered, which take on a new light given the more recent discoveries on the abundance of water in the universe. [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]

The NiII complex 1 containing pyridyl- and hydroxy-functionalized N-heterocyclic carbenes (NHCs) is synthesized and its catalytic utility for the selective nitrile hydration to the corresponding amide under base-free conditions is evaluated. The title compound exploits a hemilabile pyridyl unit to interact with a catalytically relevant water molecule through hydrogen-bonding and promotes a nucleophilic water attack to the nitrile. A wide variety of nitriles is hydrated to the corresponding amides including the pharmaceutical drugs rufinamide, Rifater, and piracetam. Synthetically challenging α-hydroxyamides are accessed from cyanohydrins under neutral conditions. Related catalysts that lack the pyridyl unit (i.e., compounds 2 and 4) are not active whereas those containing both the pyridyl and the hydroxy or only the pyridyl pendant (i.e., compounds 1 and 3) show substantial activity. The linkage isomer 1′ where the hydroxy group is bound to the metal instead of the pyridyl group was isolated under different crystallization conditions insinuating a ligand hemilabile behavior. Additional p Ka measurements reveal an accessible pyridyl unit under the catalytic conditions. Kinetic studies support a ligand-promoted nucleophilic water addition to a metal-bound nitrile group. This work reports a Ni-based catalyst that exhibits functional hemilability for hydration chemistry. [ABSTRACT FROM AUTHOR]