This work presents a novel, chlorine-free route for the synthesis of two-dimensional (2D) SnO2 via a hydrogen peroxide-assisted sol-gel method. Ammonium peroxostannate sol is used as a precursor, effectively eliminating chlorine impurities through peroxo-complex formation. Graphene oxide serves as a sacrificial template forming a 2D morphology. The obtained SnO2-2D material is characterized by an ultra-small crystallite size of similar to 5 nm and a high specific surface area (68 m(2)/g), which can withstand high temperature annealing at 500 degrees C. The SnO2-2D material demonstrates excellent performance as a hydrogen sensor, showing a high response (S = 8.9 towards 20 ppm H-2 at 250 degrees C with LOQ = 270 ppb in dry air) and maintaining significant activity under humid conditions (S = 4.5 towards 20 ppm H-2 at 400 degrees C with LOQ = 270 ppb in humid air at RH = 50 %).

Surface clogging is a dominant constraint on infiltration capacity in soil aquifer treatment (SAT), yet its evolution is hard to predict across basins whose baseline infiltration rates differ roughly 10-fold. We develop a dual machine-learning framework that predicts the full clog–recover cycle — within-segment infiltration decay and post-tillage recovery — from a ten-year, fifty-basin operational record at the Shafdan SAT facility. Both phases are expressed on scale-free log-ratio targets derived from a resistance-in-series view of clogging, which removes this baseline spread (basin medians 0.65–6.35 cm h⁻¹) and lets each model be trained across all basins rather than calibrated per basin. Generalization is stress-tested on basins withheld entirely from training — five basins fixed before training, 500 bootstrap hold-out draws, and leave-one-field-out (LOFO) cross-validation. The decay model beats a no-decay persistence baseline on every held-out basin in all 500 draws and in all 50 basins under LOFO, reducing RMSE by 0.64 cm h⁻¹ on average over persistence. Post-tillage recovery of the infiltration rate is self-restoring on average - 26% of resets return infiltration to within 10% of the previous post-tillage rate - so a no-change baseline is already strong; the recovery model improves on it consistently (11.2%), with the gain concentrated on the minority of resets that deviate from full recovery. Feature attribution identifies the drying time fraction as the leading candidate control on decay, and recovery to be associated primarily with reset timing rather than any operational feature. The two models can be interpreted as a hybrid impulsive dynamical system — a continuous decay flow punctuated by discrete tillage resets — whose stable fixed point accounts for the self-restoring character of recovery. The framework shows that infiltration dynamics transfer across unseen basins within this facility through a physically grounded, scale-free formulation, and it localizes the small set of operational levers available for management.

Hydrogen peroxide, a mediator of oxidative stress, promotes DNA damage. However, its direct interaction with purine derivatives was not previously studied. Five novel peroxosolvates of purine derivatives were synthesized: theophylline peroxosolvate, C7H8N4O2H2O2 (1); theobromine peroxosolvate, C7H8N4O2H2O2 (2); hypoxanthine peroxosolvates, 2(C5H4N4O)H2O2 (3) and 2(C5H4N4O)3(H2O2) (4); 6-benzylaminopurine peroxosolvate, C12H11N52(H2O2) (5). Their crystal structures, determined by X-ray analysis, reveal hydrogen bonding between H2O2 and the purine bases. In most structures, C-H & ctdot;O H-bonds are significant in forming two-dimensional layered motifs. Unusual cyclic (H2O2)2 dimers were observed in two structures, with a new type of H2O2 "pendulum" disorder identified in one. Solid-state DFT calculations quantified intermolecular interaction energies: similar to 35 kJ mol-1 for N-H & ctdot;O 00000000 00000000 00000000 00000000 11111111 00000000 11111111 00000000 00000000 00000000 C, 22 kJ mol-1 for N-H & ctdot;N, and similar to 20 kJ mol-1 for C-H & ctdot;OC contacts. The crystallographically characterized peroxosolvates provide structural insights into the non-oxidative interaction of H2O2 with purine bases. These models offer crucial benchmark data for computational studies of H2O2 adducts with purine derivatives.

Coordination of hydrogen peroxide by a metal center is the first step in the enzymatic cycle of peroxidases and catalases. Although this process occurs readily in living cells, synthesizing molecular complexes with the H2O2 ligand remains challenging due to hydrogen peroxide's weaker coordinating ability compared to other polar solvents. To date, structural information on coordination compounds with hydrogen peroxide as a ligand is represented by the crystal structures of a zinc complex and two tin complexes. This work demonstrates that hydrogen peroxide complexes can be prepared from coordinatively saturated compounds, such as indium(III) chloride. Ether compounds like 18-crown-6 or diethyl ether dissolve InCl3, enabling its interaction with H2O2. Three InCl3 complexes with hydrogen peroxide ligand, [InCl3(H2O)2(H2O2)]·18-crown-6, [InCl2(18-crown-6)][(H2O2)InCl4] and [fac-InCl3(H2O2)0.5(H2O)0.5(18-crown-6)], were isolated under different conditions, presenting a valuable addition to a very small family of structurally characterized H2O2 complexes. The crystal structures of these complexes were characterized by single-crystal X-ray diffraction analysis. DFT calculations unveiled the key role of the hydrogen bonding of the H2O2 ligand with ether molecules enhancing hydrogen peroxide coordination to In(III) center. Variable-temperature 1H NMR data support the κ1-coordination of H2O2 with InCl3 in ethereal solution.

Volatile organic compounds (VOCs) from historical industrial activities can persist for decades, contaminating groundwater and the unsaturated zone, yet their transport through thick, heterogeneous vadose zones is poorly understood. This study reconstructs long-term migration of tetrachloroethylene (PCE) from a former industrial site in the Jerusalem Mountains, where leakage likely began ten years after plant commissioning and systematic monitoring started decades later. A three-dimensional numerical model of flow and transport was applied, incorporating calibrated hydraulic parameters, karstic conduits, and multiphase VOC processes including advection, dispersion, phase partitioning, volatilization, and first-order degradation kinetics. Multiple model runs explored plausible leakage scenarios under sparse historical data. Simulated PCE concentrations reproduce measurements in the vadose zone (R-2 = 0.89) and deep regional aquifer (similar to 20% normalized relative error). Results reveal pronounced preferential flows horizontally through perched aquifers and vertically along discrete faults, amplified by karstic networks. The upper vadose zone remains a persistent source, sustaining gas-phase emissions toward nearby residential areas unless targeted remediation is applied. Integrated modeling, even with limited monitoring, quantitatively reconstructs complex contaminant dynamics across saturated and unsaturated compartments, providing critical guidance for remediation. Protecting groundwater and human health requires addressing both vadose and saturated zones to prevent prolonged environmental and exposure risks.

The crystallographically characterized peroxosolvates provide structural insights into the non-oxidative interaction of H 2 O 2 with purine bases.

Peroxosolvates have found wide application as a source of hydrogen peroxide for bleaching and disinfecting agents in industry, medicine, household use and organic synthesis. The key problem in their industrial production from aqueous H2O2 solutions is the isomorphic substitution of H2O2 for H2O during crystallization, driven by the similarity of hydrogen bonding networks. We report the first crystalline H2O2 adducts of primary, secondary and tertiary amine halides, synthesized from 5-97% w/w H2O2 solutions. These include peroxosolvates of aminoadamantane hydrochloride, ethylenediammonium dichloride, piperazinium dichloride and dibromide and triethylenediaminium dichloride, characterized by single crystal X-ray diffraction, elemental analysis, powder diffraction, IR spectroscopy and thermal analysis. Single-crystal XRD revealed structures stabilized by charge-assisted H-bond networks between H2O2, halide anions and organic ammonium cations. An unprecedented degree of isomorphic substitution of hydrogen peroxide by water, exceeding 50%, was discovered. The formation of peroxosolvates with H2O2/H2O isomorphous substitution was observed for all organic diammonium dihalides, suggesting a potential general trend for such coformers. Solid-state DFT calculations indicate H2O2 forms stronger H-bonds than H2O due to torsional adaptability to the distances between hydrogen bond acceptors. The synthesized peroxosolvates demonstrate relatively high thermal stability (up to 110-140 degrees C). The monoperoxosolvates of piperazinium dichloride and triethylenediaminium dichloride remain stable under ambient conditions, with a loss in relative H2O2 content of only 9.7% and 12.3%, respectively, over three months.

We present a novel thin germanium sulfide-coated Ti3C2Tx MXene electrode and evaluate its material properties and electrochemical (EC) performance as an anode for sodium-ion batteries (SIBs). The material was synthesized by depositing amorphous germanium sulfide onto Ti3C2Tx MXenes via ammonium thiogermanate decomposition under low-pH conditions, with a nonionic surfactant added to prevent MXene flocculation and control particle size. Metal chalcogenide-MXene composites show great promise as SIB anodes, benefiting from MXenes' high electrical conductivity and the enhanced specific charge capacity provided by metal alloying and conversion reactions with sodium. However, MXene-based composite anodes for SIBs remain underexplored. The proposed germanium sulfide-Ti3C2Tx composite anode demonstrates outstanding performance, achieving a specific charge capacity of 540 mAh·g-1 after 100 cycles at 1 A·g-1, surpassing all previously reported metal chalcogenide-MXene anodes. Moreover, it exhibits excellent rate capability: a 30-fold increase in current density (from 0.1 to 3 A·g-1) results in less than 15 % capacity loss. At high current densities (>1 A·g-1), the GeSx/MXene anode outperforms reduced graphene oxide (rGO)-supported GeS2 anodes synthesized via a similar protocol. These findings highlight the potential of MXene-supported GeS2 as a high-performance anode material for SIBs, paving the way for the development of next-generation MXene-based energy storage materials.

Cocrystallization with appropriate organic molecules has been known as an effective and practical strategy for stabilization of organic hydroperoxides-useful oxidants, free-radical polymerization initiators, and emerging pharmaceuticals. In this paper, two peroxosolvates (H2O2 center dot HMTA (1), 0.843H2O2 center dot 0.157H2O center dot DABCO N-oxide (2)) and 11 adducts of organic hydroperoxides (2 t BuOOH center dot DABCO (3), 2CmOOH center dot DABCO (4), 2 t BuOOH center dot HMTA (5), 3 t BuOOH center dot DABCO N-oxide (6), CmOOH center dot Ph3PO (7), Cy(OOH)2 center dot DABCO N-oxide (8), Cy(OOH)2 center dot DABCO N-oxide center dot 0.5C6H6 (9), [Cy(OOH)O]2 center dot HMTA N-oxide (10), [Cy(OOH)O]2 center dot DABCO N-oxide (11), [Cy(OOH)O]2 center dot 2DABCO N-oxide center dot 2CHCl3 (12), [Cy(OOH)O]2 center dot Ph3PO (13)) were structurally characterized for the first time, providing the relationships with the nature of components. The energetic superiority of O-H center dot center dot center dot O--N+ and O-H center dot center dot center dot O=P over O-H center dot center dot center dot N hydrogen bonds (E HB = 30.5-69.3 kJ mol-1) was against the lower basicity of amine N-oxides and Ph3PO over amine coformers. This was computationally attributed to the nearly 3-fold increase of partial atomic charges in the former hydrogen bond acceptors, in light of the interaction electrostatic nature. Nine compounds were synthesized according to the proposed facile approach and investigated by FTIR and Raman spectroscopy, thermal analysis, and powder XRD. Thermal stability of the cocrystals was found to be improved by the utilization of heavy coformers and less volatile hydroperoxides, rather than being correlated with hydrogen bond energy.

Peroxosolvates of nitrates remain a poorly studied class of compounds among the crystalline adducts of hydrogen peroxide and salts of inorganic acids. Herein, we report the synthesis, crystal structures, and FTIR and thermal studies of four hydrogen peroxide adducts of alkali metal and tetraethylammonium nitrates: KNO30.5H2O2, RbNO30.5H2O2, RbNO30.5H2O20.5H2O, and Et4N+NO3-2H2O2. The peroxosolvates of potassium and rubidium nitrates are found to be non-isomorphous. Solid state DFT calculations were performed to compare the hydrogen bond energy values of the hydrogen peroxide molecule with nitrate anions in the obtained compounds and bromide, chloride, sulfate and carbonate anions in the previously reported crystalline peroxosolvates of the corresponding salts. The calculated hydrogen bond energy values of hydrogen peroxide molecules with the anions correlate with their basicity. For the nitrate anion, these values (29.7-34.7 kJ mol-1) are higher than those for halides and lower than for sulfate and carbonate anions. In addition, the interaction of alkali metal cations with the oxygen atom of hydrogen peroxide was analyzed, revealing a non-covalent binding.

Hydrogen bonds between hydroperoxo ligands of p-block element complexes and surface functionalities of substrate particles are considered essential for sol-gel processing using hydrogen peroxide, which is effectively implemented to prepare 2D functional materials. Cocrystals of molecular organoelement hydroperoxo complexes appear to be the suitable model systems to study such interactions. This paper reports the structural and hydrogen bonding theoretical characterization of tricyclohexylgermanium hydroperoxide cocrystals with triphenylphosphine oxide, Cy3GeOOH·Ph3PO (I), and DABCO N-oxide, 2(Cy3GeOOH)·(DABCO N-oxide) (II). Additionally, cocrystal of triphenylgermanium hydroxide and DABCO N-oxide, Ph3GeOH·(DABCO N-oxide) (III), was synthesized. Crystallographic analysis demonstrated the comparable geometric parameters of hydrogen bonds donated by OOH (I, II) and OH ligands (III). Periodic DFT computations followed by Bader analysis of crystalline electron density revealed close energy values (53.2–56.2 kJ mol− 1) for the corresponding O–H⋯O−–N+ and O–H⋯O=P hydrogen bonds in I–III and allowed to classify them as intermediate interactions. Isolated cluster DFT calculations of the analogous adducts of OOH and OH organogermanium complexes showed the stronger hydrogen bonds for the former (by 6.6 or 10.3 kJ mol− 1), confirming the similarity of coordination and simple covalent hydroperoxo compounds.

Abstract Despite the significance of H2O2-metal adducts in catalysis, materials science and biotechnology, the nature of the interactions between H2O2 and metal cations remains elusive and debatable. This is primarily due to the extremely weak coordinating ability of H2O2, which poses challenges in characterizing and understanding the specific nature of these interactions. Herein, we present an approach to obtain H2O2–metal complexes that employs neat H2O2 as both solvent and ligand. SnCl4 effectively binds H2O2, forming a SnCl4(H2O2)2 complex, as confirmed by 119Sn and 17O NMR spectroscopy. Crystalline adducts, SnCl4(H2O2)2·H2O2·18-crown-6 and 2[SnCl4(H2O2)(H2O)]·18-crown-6, are isolated and characterized by X-ray diffraction, providing the complete characterization of the hydrogen bonding of H2O2 ligands including geometric parameters and energy values. DFT analysis reveals the synergy between a coordinative bond of H2O2 with metal cation and its hydrogen bonding with a second coordination sphere. This synergism of primary and secondary interactions might be a key to understanding H2O2 reactivity in biological systems.

Correction for 'Emerging pollutants in the Esmeraldas watershed in Ecuador: discharge and attenuation of emerging organic pollutants along the San Pedro-Guayllabamba-Esmeraldas rivers' by A. Voloshenko-Rossin et al., Environ. Sci.: Processes Impacts, 2015, 17, 41-53, https://doi.org/10.1039/C4EM00394B.

Means to increase water resources are essential in regions grappling with water scarcity and growing populations. Soil aquifer treatment (SAT) is a cheap, low maintenance, low-energy method to supply water for irrigation of crops consumed raw or even for drinking purposes. However, the most expensive cost-component of SATs is the land use, the infiltration basins the area of which is inversely proportional to the infiltration rate, the most important characteristic of SAT basins design and operation, which until now was believed to be time-dependent and, therefore, difficult to predict. Focusing on the Shafdan SAT in Israel as a showcase and using a decade's worth of data from 50 recharge basins, we study the time dependence of the infiltration rates. The study reveals a noteworthy consistency in the decline of effluent levels during the drainage phase across various flooding events, signifying a constant, head-independent infiltration rate. 97% of over 40,000 flooding events showed this behavior. Furthermore, the infiltration rate calculated in this manner provides good predictions of the average infiltration rate during the entire wetting phase. The water-level-independent infiltration rate is a general feature. It was found in all the 50 studied basins, regardless of the soil sand content, commissioning year, operation conditions and season. The constant infiltration rate law revealed in this study simplifies the prediction of the flooding cycle duration and will facilitate simplified predictive modeling of multiple basins SAT systems. Our research may extend beyond SAT systems, offering insights applicable to other managed aquifer recharge methods, crucial for effective water resource management, ensuring environmental compatibility.

Zinc(II) tetraammine peroxodisulfate [Zn(NH3)4]S2O8 (I) and barium peroxodisulfate tetrahydrate BaS2O8·4H2O (II) were synthesized by interaction of an aqueous solution of ammonium peroxodisulfate with a zinc peroxide and barium hydroxide, respectively. The crystal structures (CIF file CCDC nos. 2311248 (I) and 2311249 (II)) were determined by single crystal X-ray diffraction. The crystal structure of I, for which X-ray powder diffraction structural data were previously reported, has been redetermined and clarified. The crystal packing of I consists of hydrogen-bonded chains parallel to the b-axis connected in a three-dimensional structure with H-bonds between adjacent chains. The compound II is coordination polymer with coordination number of barium cation equal to 9. The crystal packing of II consists of channels in which water molecules are held by H-bonds. Compounds I and II were characterized by DTA and TGA revealing thermal stability up to 170 and 90°C.

Correction for 'Emerging pollutants in the Esmeraldas watershed in Ecuador: discharge and attenuation of emerging organic pollutants along the San Pedro-Guayllabamba-Esmeraldas rivers' by A. Voloshenko-Rossin et al., Environ. Sci.: Processes Impacts, 2015, 17, 41-53, https://doi.org/10.1039/C4EM00394B.

Highly soluble germanium oxide, an amorphous macroreticular form of germanium oxide, was used as a precursor for the deposition of GeS2 on reduced graphene oxide (rGO) through a low-temperature, wet-chemistry process. Thermal treatment of the solid provided an ultrathin rGO - supported amorphous GeS2 coating. The GeS2@rGO composite was tested as a lithium ion battery (LIB) anode. Leveraging the versatility of wet chemistry processing, we employed strategies initially developed for mitigating polysulfide shuttle effects in lithium-sulfur batteries to enhance anode performance. The anode exhibited exceptional stability, surpassing 1000 cycles, with charge capacities exceeding 1220 and 870 mAh.g 1 at rates of 2 and 5 A.g- 1, respectively. Performance improvements were achieved by minimizing GeS2 grain size using the non-ionic surfactant Triton X-100 during synthesis and preventing polysulfide shuttle effects through a negatively charged thick glass fiber separator, fluoroethylene carbonate additive (FEC) in EC:DEC (ethylene carbonate: diethyl carbonate) solvent, and a polyacrylic acid (PAA) binder. These cumulative modifications more than tripled the charge capacity of the germanium sulfide LIB anode. Feasibility was further demonstrated through full cell studies using a LiCoO2 counter electrode.

Carbonate electrolytes are one of the most desirable electrolytes for high-energy lithium-sulfur batteries (LSBs) because of their successful implementation in commercial Li-ion batteries. The low-polysulfide-solubility feature of some carbonate solvents also makes them very promising for overcoming the shuttle effects of LSBs. However, regular sulfur electrodes experience undesired electrochemical mechanisms in carbonate electrolytes due to side reactions. In this study, we report a catalytic redox mechanism of sulfur in propylene carbonate (PC) electrolyte based on a comparison study. The catalytic mechanism is characterized by the interactions between polysulfides and dual N/O functional groups on the host carbon, which largely prevents side reactions between polysulfides and the carbonate electrolyte. Such a mechanism coupled with the low-polysulfide-solubility feature leads to stable cycling of LSBs in PC electrolyte. Favorable dual N/O functional groups are identified via a density functional theory study. This work provides an alternative route for enabling LSBs in carbonate electrolytes.

Germanium and germanium-based compounds are widely used in microelectronics, optics, solar cells, and sensors. Recently, germanium and its oxides, nitrides, and phosphides have been studied as active electrode materials in lithium- and sodium-ion battery anodes. Herein, the newly introduced highly soluble germanium oxide (HSGO) was used as a versatile precursor for germanium-based functional materials. In the first stage, a germanium-dioxide-reduced graphene oxide (rGO) composite was obtained by complete precipitation of GeO2 nanoparticles on the GO from an aqueous solution of HSGO and subsequent thermal treatment in argon at low temperature. The composition of the composite, GeO2-rGO (20 to 80 wt.% of crystalline phase), was able to be accurately determined by the HSGO to GO ratio in the initial solution since complete deposition and precipitation were achieved. The chemical activity of germanium dioxide nanoparticles deposited on reduced graphene oxide was shown by conversion to rGO-supported germanium nitride and phosphide phases. The GeP-rGO and Ge3N4-rGO composites with different morphologies were prepared in this study for the first time. As a test case, composite materials with different loadings of GeO2, GeP, and Ge3N4 were evaluated as lithium-ion battery anodes. Reversible conversion–alloying was demonstrated in all cases, and for the low-germanium loading range (20 wt.%), almost theoretical charge capacity based on the germanium content was attained at 100 mA g−1 (i.e., 2595 vs. 2465 mAh g−1 for Ge3N4 and 1790 vs. 1850 mAh g−1 for GeP). The germanium oxide was less efficiently exploited due to its lower conversion reversibility.

Barium stannate is a mixed-metal oxide with a perovskite structure and unique electric, catalytic, and sensing properties. Surface chemistry determines gas sensing behavior, which depends on materials synthesis and processing methods. A novel technique was invented for obtaining BaSnO3 nanoparticles using a hydrogen peroxide assisted sol-gel process. However, to date, the sensing behavior of such prepared barium stannate nanoparticles has not been investigated. In this work, we obtained pure and La-modified BaSnO3 by the hydrogen peroxide-assisted sol-gel method and comparatively studied the composition, microstructure, and gas sensing behavior using as a reference barium stannate prepared by a conventional hydrothermal route. The increased sensitivity and selectivity to H2S were observed for the sol-gel obtained BaSnO3, and the sensing behavior was improved at temperatures higher than 150 degrees C by La(5%)-modified of barium stannate. The sensing mechanism was revealed by in situ infrared and Raman spectroscopy. The superior sensitivity and selectivity of the sol-gel obtained materials were attributed to lower surface contamination by adsorbed carbonate groups compared to hydrothermally obtained BaSnO3. The surface modification by La3+ species further reduced the carbonate impurity and enhanced the adsorption and oxidation of H2S gas at the BaSnO3 surface. (c) 2023 Elsevier B.V. All rights reserved.