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The kinetics of the reaction of hydroxyl radical (OH) with trimethyl phosphate (CH3O)3PO (TMP) (reaction (1)) OH + TMP → products (1) was studied at the bath gas (He) pressure of 1 bar over the 273–837 K temperature range. Hydroxyl radicals were produced in fast reactions of electronically excited oxygen atoms O(1D) with either H2O or H2. Excited oxygen atoms O(1D) were produced by photolysis of ozone, O3, at 266 nm (4th harmonic of Nd:YAG laser) over the 273–470 K temperature range and by photolysis of N2O at 193 nm (ArF excimer laser) over the whole temperature range including the elevated temperature range 470–837 K. The reaction rate constant exhibits a V-shaped temperature dependence, negative in the low temperature range, 273–470 K (the rate constant decreases with temperature), and positive in the elevated temperature range, 470–837 K (the rate constant increases with temperature), with a turning point at 471 K. The rate constant could be fairly well fitted with the three parameter modified Arrhenius expression, k1 = 7.52 × 10−18 (T/298)9 exp(34 367 J mol−1/RT) cm3 per molecule per s (273–837 K). Previously, only one indirect experimental measurement at a single (ambient) temperature was available. The temperature dependence over an extended temperature range obtained in this study together with the peculiar V-shaped temperature dependence will have an impact on the modelling of the flame inhibition by phosphates as well on the further understanding of the mechanisms of elementary chemical reactions.

The near-limit oscillatory behaviors on wick flames of dimethyl carbonate (DMC) with trimethyl phosphate (TMP) additions have been investigated experimentally. The experiments were conducted under a wick burner in conjunction with the limiting oxygen concentration test (wick-LOC), and the fuels were selected as typical examples of electrolyte solvents and organophosphorus compounds (OPCs) for lithium-ion batteries. The near-limit oscillating flames on the wick configuration were observed into two main characters: side-to-wake or side oscillation in for the side-stabilized flame (full flame) and wake oscillation for the wake-stabilized flame (wake flame). By tracing the flame base movement using a 240-fps camera, stable limit cycle oscillations were found in full flame cases, while the wake flame cannot sustain the oscillation for long and finally leads to global extinction. With the addition of TMP in DMC, the transition from the side-to-wake oscillation to the side oscillation was found in the unstable full flames with a linear increase in frequency and a significant drop in amplitude, while the wake oscillating flames performed increased trends for both. To clarify the dominant mechanism of TMP-added flame oscillations, laminar burning velocities of DMC+TMP mixtures were calculated at the oxygen level of each near-limit oscillating flame. The weakened flame speed with TMP addition revealed the inadequacy of buoyancy-driven mechanisms for the OPC added wick-flame. Then the wick surface temperature was measured adopting a special thermocouple arrangement to validate the thermal-diffusive promotion by TMP addition. Results showed that the heat feedback from TMP-added flames compensated for the low reactivity and provided a faster oscillation near the extinction limit.

The practical application of nonflammable highly salt-concentrated (HC) electrolyte is strongly desired for safe Li-ion batteries. Not only experimentalists but also theoreticians are extensively focusing on the dilution approach to address the limitations of HC electrolyte such as low ionic conductivity and high viscosity. This study suggests promising highly-fluorinated ethers to dilute the HC electrolyte based on non-flammable trimethyl phosphate (TMP) solvent. According to the quantum mechanical and molecular dynamics calculations, the fluorinated ether diluents showed a miscibility behavior in HC TMP-based electrolyte. While such miscibility behavior of the diluent with TMP solvent has been significantly enhanced by increasing its degree of fluorination, i.e., the “fluorous effect”, it is remarkable that the self-diffusion constant of Li+ and the ionic conductivity should be significantly improved by dilution with bis(1,1,2,2-tetrafluoro ethyl) ether (B2E) and bis(pentafluoro ethyl) ether (BPE) compared to other common hydrofluoroether diluents. In addition, the fluorinated-ether diluents have high ability to form a localized-concentrated electrolyte in HC TMP-based solution, leading to high expectation for the formation of a stable and a compact inorganic SEI film.

Flammability studies of electrolytes are required for screening safer materials used in lithium-ion batteries. Besides the thermal stability, the effects of lithium salts on electrolyte combustion are important as well for fire safety of electrolytes. To clarify the influence of lithium salts on the electrolyte flammability, experimental analyses were conducted using a unique wick combustion system in conjunction with the limiting oxygen concentration (LOC) test, called wick-LOC method. The dimethyl carbonate (DMC)-based electrolytes with 1M addition of different lithium salts (LiPF6, LiBF4, and LiTFSI) were studied comparing with pure DMC and trimethyl phosphate (TMP)-added solvents. The three lithium salts gave unique and distinct flame behaviors including flame shapes, colors and the changes of wick surface until self-extinguishing. The wick-LOC results indicated a considerable flame-retardant effect of LiPF6, while other salts have minor effects on the flame extinction. Utilizing the flame spectrum and combustion residue analyses, the roles of salts during combustion were characterized. The PF6 anion played a similar role with the TMP additive in the gas phase flame inhibition. In the cases of LiPF6 and LiBF4, the solid products (LiF) accumulation blocked the fuel supply from the wick to the flame region. In the case of LiTFSI, the serious charring of the cotton wick was considered as a potential hazard on solid combustibles in the real fire scenarios.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) The trimethyl phosphate molecule is an important prototype for studying electron interactions with molecules of biological significance containing the phosphate group. These studies contribute to the understanding of energy transfer processes in living organisms and have an application in radiotherapy and radio-diagnostic techniques development. In this context, we present an experimental and theoretical study on the interaction of electrons with this molecule. Experimentally, elastic differential cross sections data were obtained in the energy range from 5 to 800 eV within the angular range from 10◦ to 130◦ using the relative flow technique. Momentum transfer cross sections were determined by the integration of differential cross sections in the same energy range. Experimental data for the dissociative ionization pattern in the region extending from the ionization threshold to 1000 eV were also obtained. Theoretically, elastic differential cross sections and total ionization cross sections were calculated using the independent atom model and the binary-encounter Bethe model, respectively. For the latter, different density functionals were investigated. The experimental and theoretical results were compared with the literature for trimethyl phosphate and other molecules of the same category of phosphate esters. In overall, a good agreement is observed. The elastic cross sections data have recently been published [F. P. Bardela et al., Elastic electron collisions with trimethyl phosphate, J. Phys. B: At. Mol. Opt. Phys. 54 075203 (2021)]. A molécula de trimetil fosfato é um importante modelo para o estudo das interações de elétrons com moléculas de interesse biológico que contém o grupo fosfato. Esses estudos colaboram para a compreensão dos processos de transferência de energia em organismos vivos e tem aplicação direta no desenvolvimento de técnicas de radioterapia e radiodiagnóstico. Nesse contexto, apresentamos um estudo experimental e teórico sobre a interação de elétrons com esta molécula. Experimentalmente, dados de seções de choque diferenciais elásticas foram obtidas na faixa de energia de 5 a 800 eV dentro do intervalo angular de 10◦ a 130◦ empregando-se a técnica de fluxo relativo. Seções de choque de transferência de momento foram determinadas a partir da integração das seções de choque diferenciais na mesma faixa de energia. Dados experimentais para o padrão de ionização dissociativa na região que se estende do limiar de ionização até 1000 eV também foram obtidos. Teoricamente, seções de choque diferenciais elásticas e seções de choque de ionização total foram calculadas empregando-se o modelo de átomos independentes e o modelo de encontro binário de Bethe, respectivamente. Para este último, diferentes funcionais densidade foram investigados. Os resultados experimentais e teóricos foram comparados com outros disponíveis na literatura para o trimetil fosfato e outras moléculas da mesma classe de ésteres fosfatados, sendo que em geral, uma boa concordância pode ser observada. Os dados de seções de choque elásticas foram recentemente publicados [F. P. Bardela et al., Elastic electron collisions with trimethyl phosphate, J. Phys. B: At. Mol. Opt. Phys. 54 075203 (2021)]. 88887.353672/2019-00

Solvent engineering by Lewis‐base solvent and anti‐solvent is well known for forming uniform and stable perovskite thin films. The perovskite phase crystallizes from an intermediate Lewis‐adduct upon annealing‐induced crystallization. Herein, it is explored the effects of trimethyl phosphate (TMP), as a novel aprotic Lewis‐base solvent with a low donor number for the perovskite film formation and photovoltaic characteristics of perovskite solar cells (PSCs). As compared to dimethylsulfoxide (DMSO) or dimethylformamide (DMF), the usage of TMP directly crystallizes the perovskite phase, i.e., reduces the intermediate phase to a negligible degree, right after the spin‐coating, owing to the high miscibility of TMP with the anti‐solvent and weak bonding in the Lewis adduct. Interestingly, the PSCs based on methylammonium lead iodide (MAPbI3) derived from TMP/DMF‐mixed solvent exhibit a higher average power conversion efficiency of 19.68% (the best: 20.02%) with a smaller hysteresis in the current‐voltage curve, compared to the PSCs that are fabricated using DMSO/DMF‐mixed (19.14%) or DMF‐only (18.55%) solvents. The superior photovoltaic properties are attributed to the lower defect density of the TMP/DMF‐derived perovskite film. The results indicate that a high‐performance PSC can be achieved by combining a weak Lewis base with a well‐established solvent engineering process., A low defect halide perovskite film can be fabricated using trimethyl phosphate (TMP). TMP directly forms perovskite without intermediate phase due to weak Lewis basicity. The TMP‐based film reduces hysteresis in current‐voltage curve of perovskite solar cell. The TMP‐based device exhibits better performance (>20%) than other solvent‐based ones.

It is well known that ring-opening polymerization (ROP) of sterically unhindered cyclic ethylene phosphates, initiated by both organocatalysts and coordination catalysts, is accompanied by transesterification (TE) even at subzero temperatures. To clarify this phenomenon from the mechanistic point of view, we calculated (DFT, B3PW91/DGTZVP) the reaction profiles of the ROP for 2-methoxy-1,3,2-dioxaphospholane-2-oxide (methyl ethylene phosphate, MeOEP) and of the transesterification processes for poly(MeOEP) and trimethyl phosphate (TMP) in the presence of 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) organocatalyst. We found that the free activation energy of TE is substantially higher (10–13 kcal/mol) than the ROP activation barrier. To verify the calculation results, we investigated the chemical behavior of low molecular weight trimethyl phosphate (TMP) in the TBD-catalyzed polymerization of MeOEP. We demonstrated that TMP was not affected by transesterification, which correlates with the calculation results. However, we found that the polymerization of MeOEP in the presence of TMP leads to the formation of linear poly(MeOEP) with given Pn and narrow MWD even at >99% monomer conversion degree. A similar pattern was revealed for the synthesis of poly(MeOEP) with the coordination catalyst of aryloxy-alkoxy magnesium complex [(BHT)Mg(μ-OBn)(THF)]2 (BHT = 2,6-di-tert-butyl-4-methylphenoxy). To explain the difference in the chemical behavior of TMP and polyphosphate, we assumed that poly(MeOEP) in the solution represents a dense globule, which leads to a decrease in the entropy of transesterification. To confirm this assumption, we studied the solution behavior of poly(MeOEP) in CHCl3 and in TMP. Both CHCl3 and TMP were found to be poor solvents for poly(MeOEP) in terms of KMH solution theory (α = 0.53 and 0.33, respectively). We assume that it is the conformation of the polymer in the solution that determines the tendency of the polyphosphate towards transesterification.

Organophosphorus compounds (OPCs) have long been known to have significant fire suppression capabilities but were outclassed by Halon 1301 due to toxicity concerns. Recent interest in finding replacements for Halon 1301 has provided an impetus to reconsider OPCs. To better understand the mechanism by which OPCs suppress flames, more information about how they interact with fuel/air mixtures via chemical kinetics is needed. In this study, dimethyl methylphosphonate (DMMP), diethyl methylphosphonate (DEMP), and trimethyl phosphate (TEP) were added to hydrogen/air and methane/air mixtures to assess their suppression capabilities at 0.1% and 0.3% (DMMP only) of the total mixture volume. Laminar flame speed experiments were performed in an optically tracked, spherically expanding flame setup at 1 atm and 120 °C. The resulting laminar flame speed data are the first to be recorded using these compounds. Results show a 30% decrease in laminar flame speed for all OPCs at 0.1% on the methane/air parent mixture, and the laminar flame speed curves, as a function of equivalence ratio, tend to be broader than for un-doped mixtures. For the hydrogen/air mixtures, the OPCs differentiate themselves by having an increasing suppression effect corresponding with higher carbon moiety, i.e., TEP (15% overall reduction) > DEMP (13%) > DMMP (9%). The OPCs also have an increasing effect with increasing equivalence ratio on hydrogen/air, but with methane/air, they have a non-monotonic effect. The reduction of laminar flame speeds is comparable to twice the concentration of Halon 1301 and 10 times as much for previously investigated Halon 1301 replacements. These results are ideal for improving existing OPC chemical kinetics mechanisms, and possible applications include both fire suppression technologies and destruction of dangerous OPC compounds.

Potassium-ion batteries are now regarded as powerful competitors to lithium-ion batteries due to their merits of low-cost and abundant resource contrasted with state-of-art lithium ion batteries. However, the extremely flammable electrolytes may cause severe safety issues. Herein, we report an intrinsic non-flammable trimethyl phosphate-based potassium ion battery electrolyte. The problem of its poor electrochemical compatibility with graphite electrode is successful settled by using concentrated salt electrolyte. Graphite anode with high concentrated potassium bis(fluorosulfonyl)imide (KFSI)/trimethyl phosphate (TMP) electrolyte demonstrates high Coulombic efficiency and stable cyclability after 80 cycles. The performance enhancement mechanism is further probed via X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy, and scanning electron microscopy (SEM). The flame-retarding character of the concentrated electrolyte with stable electrochemical performance paves the way toward low cost and highly safe potassium ion batteries.

A zero-waste, environmentally friendly production process of a plant growth regulator, N,N-di(2-hydroxyethyl)-N,N-dimethylammonium dimethyl phosphate, has been developed which makes it possible to obtain the target product in a yield of up to 99.8%. The developed process has been successfully scaled up from the laboratory scale to pilot and further industrial scales.

Electrodeposited cobalt phosphate has been reported in the literature as a robust alternative to noble metal-based electrocatalysts for the O2 evolution reaction. In parallel, atomic layer deposition (ALD) has been acknowledged as a key technology for the preparation of thin films for energy applications. With the present work, the authors have addressed the preparation of cobalt phosphate thin films by a plasma-assisted ALD process. The process developed consists of cobaltocene (step A) and trimethyl phosphate (step C) exposures alternated by O2 plasma (steps B and D) in an ABCD fashion. The process shows a linear growth with a growth per cycle of 1.12 ± 0.05 Å at 300 °C and no nucleation delay. The ALD saturation behavior has been demonstrated for each dosing step, and the process shows minimal inhomogeneity on 100 mm diameter wafers in terms of film thickness (

The methylation of lignin is a key reaction for many different purposes, such as increasing the thermal stability and controlling lignin functionality for polymer applications, and increasing the yield of aromatic hydrocarbons during lignin pyrolysis. Methylation most often requires the use of toxic reagents, such as dimethyl sulfate. We developed an alternative protocol based on trimethyl phosphate as a safer and milder methylating reagent. The reaction proceeds without a solvent for only one hour to ensure complete and selective methylation of phenolic hydroxyl groups. This specific protocol was successfully applied to several lignins from different botanical origins (softwood, hardwood, and annual plants) and fractionation processes (Kraft, soda, and organosolv). This approach further allows a precise control of methylation in order to prepare lignins with tunable contents of phenolic hydroxyl groups for a large range of potential applications.

The ever-growing global economy implies a steadily increasing demand for more portable energy sources, currently relying mostly on Li-ion technology. In this context, the market is continuously asking for improved performances from Li-ion batteries (LIBs). Furthermore, not only the consumer needs are driving the research toward higher standards but also the global energy demand growth, evermore pressing the need of a cleaner and more sustainable energy supply chain. Yet LIBs are well-optimized devices and going beyond what is the current state-of-the art in the battery field entails to explore new materials and components. The quest for better batteries has shed light on materials and technologies promising improved levels of sustainability, cost-effectiveness, power density and/or energy density. In that respect, significant efforts are devoted to new organic positive electrode materials that could supersede their inorganic counterparts at all levels mentioned beforehand. The goal of this thesis is to develop new concepts to allow a successful implementation of redox organics as positive electrode materials without any trade-off over their current inorganic counterparts. To that end, we explored different strategies based on: (i) the design of hybrid materials with near-ideal dispersion properties thanks to the covalent grafting of our nitroxide-bearing polymers on conductive carbon nanotubes, (ii) the design of a cross-hybrid structure merging the conducting properties of polyaniline with the high specific capacity of quinone redox moieties, (iii) the modulation of electrode potentials driven by changes of electrolyte composition to increase the battery voltage output. (SC - Sciences) -- UCL, 2020

Despite their beneficial effect on battery safety, non-flammable electrolytes often have an adverse side effect on the electrochemical performance of lithium and sodium ion batteries due to their poor compatibility with the electrodes. In this paper, we report a new non-flammable electrolyte consisting of trimethyl phosphate (TMP) and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (F-EPE) as non-flammable solvents and fluoroethylene carbonate (FEC) as additive with different concentration of Na salts, and a EC-DEC-FEC electrolyte was also prepared as baseline electrolyte. The flammability and non-flammability of the prepared electrolytes was tested. It is shown that the prepared electrolyte not only increases the capacity (129.9 vs. 122.5 mAh g−1 of baseline electrolyte) of NaNi1/3Fe1/3Mn1/3O2 (NFM) cathode but also stabilizes the cyclability (70.8% retention after 500 cycles) of NFM/HC (HC: hard carbon) pouch cells. The dissolution of pristine NaNi1/3Fe1/3Mn1/3O2 cathode material in different solvents and electrolytes, and the XPS patterns of the cycled NFM cathode in the prepared electrolytes were also studied to understand the capacity fading mechanism. These results indicate that this new non-flammable electrolyte holds great potential for application in rechargeable sodium-ion batteries. Keywords: Sodium-ion battery, Non-flammability, Safe electrolyte, Hydrofluoroether, Phosphate

Atomic layer deposition (ALD) of lithium-containing films is of interest for the development of next-generation energy storage devices. Lithium hexamethyl disilazide (LiHMDS) is an established precursor to grow these types of films. The LiHMDS molecule can either be used as a single-source precursor molecule for lithium or as a dual-source precursor molecule for lithium and silicon. Single-source behavior of LiHMDS is observed in the deposition process with trimethylphosphate (TMP) resulting in the deposition of crystalline lithium phosphate (Li3PO4). In contrast, LiHMDS exhibits dual-source behavior when combined with O2 plasma, resulting in a lithium silicate. Both processes were characterized with in situ ellipsometry, in situ time-resolved full-range mass spectrometry, X-ray photoelectron spectroscopy (XPS), and elastic recoil detection analysis (ERDA). When we combined both reactants into a three-step LiHMDS-TMP-O2* or LiHMDS-O2*-TMP process, the dual-source nature of LiHMDS emerged again. By carefully combining our measurements, it is shown that film growth with LiHMDS (in combination with TMP and O2 plasma) is driven by dipole-driven self-saturated surface interactions combined with dissociative chemisorption. We show that when hydroxyl groups are present on the surface, silicon will be incorporated in the films. These insights benefit the general understanding of the behavior of the LiHMDS and TMP precursors and may facilitate their effective use in ternary or quaternary processes. peerReviewed

In situ nitrogen doping of aluminum phosphate has been investigated in two different plasma-enhanced atomic layer deposition (PEALD) processes. The first method consisted of the combination of trimethyl phosphate plasma (TMP*) with a nitrogen plasma and trimethyl aluminum (TMA), that is, TMP*-N-2*-TMA. The second method replaces TMP* with a diethylphosphoramidate plasma (i.e., DEPA*-N-2*-TMA) of which the amine group could further aid nitrogen doping and/or eliminate the need for a nitrogen plasma step. At a substrate temperature of 320 degrees C, the TMP*-based process showed saturated growth (0.8 nm/cycle) of a nitrogen-doped (approximately 8 atom %) Al phosphate, while the process using DEPA* showed a similar amount of nitrogen but a significantly higher growth rate (1.4 nm/cycle). In the latter case, nitrogen doping could also be achieved without the nitrogen plasma, but this leads to a high level of carbon contamination. Both films were amorphous as-deposited, while X-ray diffraction peaks related to AlPO4 appeared after annealing in a He atmosphere. For high coating thickness (>2 nm), a significant increase in the Li-ion transmittance was found after nitrogen doping, although the coating has to be electrochemically activated. At lower thickness scales, such activation was not needed and nitrogen doping was found to double the effective transversal electronic conductivity. For the effective transversal ionic conductivity, no conclusive difference was found. When a lithium nickel manganese cobalt oxide (NMC) powder is coated with one ALD cycle of N-doped Al phosphate, the rate capability and the energy efficiency of the electrode improves.

Sodium-ion batteries based on all-naturally-abundant elements, in which no cobalt, nickel, copper, and fluorine is used, can lead to a major breakthrough in making batteries more sustainable. Safety aspects -in particular flammability of electrolytes- in the state-of-theart battery technology is another important concern, especially for applications in which large numbers of cells are employed. Non-flammable battery electrolytes studied so far are based on highly fluorinated compounds or high salt concentrations, which suffer from high cost and toxicity. We here propose an electrolyte based on a single solvent and lowcost and fluorine-free salt at the lower range of “standard” concentrations. Our results show -for the first time- that sodium bis(oxalato)borate (NaBOB) is soluble in the nonflammable solvent trimethyl phosphate (TMP). This finding enables a non-flammable electrolyte with high ionic conductivity and promising electrochemical performance in fullcell sodium-ion batteries. An electrolyte of 0.5 M NaBOB in TMP provides ionic conductivity of 5 mS cm-1 at room temperature, which is comparable to commonly used electrolytes based on sodium hexafluorophosphate (NaPF6) and organic carbonate solvents. The proposed electrolyte shows the Coulombic efficiency of above 80% in the first cycle, which increased to about 97% from the second cycle in sodium-ion battery fullcells consisting of a hard carbon anode and Prussian white cathode. This work opens up new opportunities to design safe electrolytes which can further be optimized with electrolyte additives such as vinylene carbonate for industrial applications.

Levels of eleven organophosphate esters (OPEs) were measured in particle phase atmospheric samples collected at Bohai Sea and northern Yellow Sea in China. The concentration of ∑11OPEs in atmospheric particles ranged from 426 to 3933 pg/m3, with the mean concentration of 1412 pg/m3. Tris(1-chloro-2-propyl) phosphate (TCPP) and triphenyl-phosphine oxide (TPPO) were the most abundant OPE congeners measured, and the individual concentrations of trimethyl phosphate (TMP), tri-iso-butyl phosphate (TiBP), tri-n-butyl phosphate (TnBP), tris(1,3-dichloro-2-propyl) phosphate (TDCP), triphenyl phosphate (TPhP), 2-ethylhexyl diphenyl phosphate (EHDPP), TPPO and tri-m-cresyl phosphate (TMTP) in atmospheric particles above the Bohai Sea were higher than those above the northern Yellow Sea. The estimated atmospheric dry deposition fluxes ranged from 202 to 1869 ng/m2/day. Up to 18.3 ± 12.5 ton/year of OPEs can be loaded to the Bohai Sea.

In this communication, a new class of task-specific ionic liquids (ILs) with cationic rare earth elements (REEs) is reported. These novel ILs have a wide electrochemical window of about 6 V, enabling direct electrodeposition of REE metals at room temperature. The ILs were prepared by dissolving bis(trifluoromethane)sulfonimide (NTf2−) based rare earth salts (Ln(NTf2)3) (Ln:Lanthanide) in trimethyl phosphate (TMP) neutral ligand. Specifically, four REEs (Nd, Dy, Gd, and Pr) have been investigated in TMP based IL systems. All four metals were successfully deposited at room temperature. This demonstrates the applicability of the IL systems for electrodeposition of a wide range of REEs, which opens a new avenue of research for the quest to supplant high temperature molten salt systems for rare earth deposition. Keywords: Electrodeposition, Ionic liquids, Rare earth elements, Room temperature, Neutral ligand

The conformational switching of trimethyl phosphate (TMP) in Ne, Ar, Kr and Xe matrixes was studied using infrared spectroscopy under isolated conditions at low temperatures. In all the inert matrixes, the vapor phase population of ground state C3(G±G±G±) and the higher energy C1(TG±G±) conformers of TMP is preserved during the initial deposition. However, on annealing the inert Ar/Kr/Xe matrixes, the conformational composition of TMP was irreversibly altered. In Ar and Kr matrixes, an interconversion from ground state C3(G±G±G±) to higher energy C1(TG±G±) conformer was observed whereas Xe presents an interesting variation. In Xe matrix, the higher energy C1(TG±G±) conformer completely depopulated with a concomitant increase in the population of the ground state C3(G±G±G±) conformer. In Ne matrix notably, no conformational interconversion was observed. Computations on the conformers of TMP were performed using B3LYP and M06-2X levels of theory with 6-311++G(d,p) and aug-cc-pVDZ basis sets. The effect of inert matrixes was modeled using Self-Consistent Reaction Field (SCRF) methods.

In this study, phosphorus modification by trimethyl phosphate impregnation was employed to enhance the hydrothermal stability of nano-sized HZSM-5 zeolites. A parallel modification was studied by ammonium dihydrogen phosphate impregnation. The modified zeolites were subjected to steam treatment at 800 °C for 4 h (100% steam) and employed as catalysts for olefin catalytic cracking (OCC) of full-range fluid catalytic cracking (FCC) gasoline. X-ray diffraction, N2 physical adsorption and NH3 temperature-programmed desorption analysis indicated that, although significant improvements to the hydrothermal stability of nano-sized HZSM-5 zeolites can be observed when adopting both phosphorus modification strategies, impregnation with trimethyl phosphate displays further enhancement of the hydrothermal stability. This is because higher structural crystallinity is retained, larger specific surface areas/micropore volumes form, and there are greater numbers of surface acid sites. Reaction experiments conducted using a fixed-bed micro-reactor (catalyst/oil ratio = 4, time on stream = 4 s) showed OCC of full-range FCC gasoline—under a fluidized-bed reaction mode configuration—to be a viable solution for the olefin problem of FCC gasoline. This reaction significantly decreased the olefin content in the full-range FCC gasoline feed, and specifically heavy-end olefins, by converting the olefins into value-added C2–C4 olefins and aromatics. At the same time, sulfide content of the gasoline decreased via a non-hydrodesulfurization process. Nano-sized HZSM-5 zeolites modified with trimethyl phosphate exhibited enhanced catalytic performance for OCC of full-range FCC gasoline.

An optical waveguide (OWG) sensor was developed for real-time detection of diethyl chlorophosphate (DCP) vapor, which is a typical simulant for organophosphorus pesticides and chemical weapon agents. Silica gel, crystal violet (CV), and potassium ion-exchange (PIE) OWG were used to fabricate the sensor&rsquo, s device. In the real-time detection of the DCP vapor, the volume fraction of DCP vapor was recorded to be as low as 1.68 &times, 10&minus, 9. Moreover, the detection mechanism of CV-SiO2 gel film coated the PIE OWG sensor for DCP, which was evaluated by absorption spectra. These results demonstrated that the change of output light intensity of the OWG sensor significantly increased with the augment of the DCP concentration. Repeatability as well as selectivity of the sensors were tested using 0.042 &times, 6 and 26.32 &times, 6 volume fraction of the DCP vapor. No clear interference with the DCP detection was observed in the presence of other common solvents (e.g., acetone, methanol, dichloromethane, dimethylsulfoxide, and tetrahydrofuran), benzene series (e.g., benzene, toluene, chlorobenzene, and aniline), phosphorus-containing reagents (e.g., dimethyl methylphosphonate and trimethyl phosphate), acid, and basic gas (e.g., acetic acid and 25% ammonium hydroxide), which demonstrates that the OWG sensor could provide real-time, fast, and accurate measurement results for the detection of DCP.

We investigated the inhibitory effects of 13 organophosphate esters (OPEs) and hydrolytic metabolites on the carboxylesterase activity of rat liver microsomes in vitro in order to examine whether there might be a potential impact on human health, and to elucidate the structure activity relationship. Among the test compounds, 2-ethylhexyl diphenyl phosphate (EDPhP) was the most potent inhibitor of carboxylesterase activity, as measured in terms of 4-nitrophenol acetate hydrolase activity, followed by tri-m-cresyl phosphate (TmCP), cresyl diphenyl phosphate (CDPhP) and triphenyl phosphate (TPhP). The IC50 values were as follows: EDPhP (IC50: 0.03 μM) > TmCP (0.4 μM) > CDPhP (0.8 μM) > TPhP (14 μM) > tris(1,3-dichloro-2-propyl) phosphate (17 μM) > tris(2-ethylhexyl) phosphate (77 μM) > tri-n-propyl phosphate (84 μM) > tris(2-chloroethyl) phosphate (104 μM) > tris(2-butoxyethyl) phosphate (124 μM) > tri-n-butyl phosphate (230 μM). The IC50 value of EDPhP was three orders of magnitude lower than that of bis(4-nitrophenyl) phosphate, which is widely used as an inhibitor of carboxylesterase. Trimethyl phosphate, triethyl phosphate and tris(2-chloroisopropyl) phosphate slightly inhibited the carboxylesterase activity; their IC50 values were above 300 μM. Lineweaver-Burk plots indicated that the inhibition by several OPEs was non-competitive. Diphenyl and monophenyl phosphates, which are metabolites of TPhP, showed weaker inhibitory effects than that of TPhP.

The selective recovery of gold from wastewater is necessary because it is widely used in various fields. In this study, a new polymeric adsorbent (TP-AFC) was prepared by modifying polyaniline with trimethyl phosphate for the selective recovery of gold from wastewater. Bath experiments were carried out to explore the adsorption capacity and mechanism. The optimum pH of adsorption is 4. The adsorption equilibrium is reached at 840 min. The maximum adsorption capacity is 881 mg/g and the adsorption was a spontaneous endothermic process. The adsorption process fitted well with pseudo second-order kinetic and the Langmuir-models. The single-layer chemisorption governed the adsorption process. In addition, the application in wastewater indicated that the interfering ions had no effect on the adsorption of gold ions. TP-AFC has good selectivity. The interaction mechanism was mainly ion exchange and complexation. In general, TP-AFC was successfully prepared and has an excellent future in practical application.

Rechargeable sodium-ion batteries are considered promising candidates for low-cost and large-scale energy storage systems. However, the limited energy density, cyclability, and safety issues remain challenges for practical applications. Herein, investigation of the Cu1.8S/C composite material as the negative electrode active (conversion) material in combination with a concentrated electrolyte composed of a 3.3 m solution of sodium bis(fluorosulfonyl)imide (NaFSI) in trymethyl phosphate and fluoroethylene carbonate (FEC) as the additive is reported on. Such a combination enables the stable cycling of the conversion-type Cu1.8S/C electrode material for hundreds of cycles with high capacity (380 mAh g−1). Both the salt (NaFSI) and the additive (FEC) contribute to the formation of a stable NaF-rich solid electrolyte interphase (SEI) on the anode surface. A full cell using the Na3V2(PO4)3/C cathode also demonstrates stable cycling performance for 200 cycles with a promising Coulombic efficiency (CE) (99.3%). These findings open new opportunities for the development of safer rechargeable sodium-ion batteries.

An experimental investigation of elastic electron scattering by trimethyl phosphate (C3H9PO4) is presented. Differential cross sections were measured in the 5–800 eV and 10°–130° and from these data momentum-transfer cross sections were derived. Calculations of the scattering cross sections in the intermediate energy range were performed within the independent atom model framework at static-exchange-polarization plus absorption level of approximation. The comparison between our measured and calculated results presents, in general, a good agreement.

Three complexes with boron trifluoride (BF3) as the Lewis acid and different Lewis bases were synthesized and used as electrolyte additives in Li[Ni1/3Mn1/3Co1/3]O2/graphite and Li[Ni0.42Mn0.42Co0.16]O2/graphite pouch cells. Lewis acid-base adducts with a boron-oxygen (B O) bond were trimethyl phosphate boron trifluoride (TMP-BF) and triphenyl phosphine oxide boron trifluoride (TPPO-BF). These were compared to pyridine boron trifluoride (PBF) which has a boron-nitrogen (B N) bond. The experimental results showed that cells with PBF had the least voltage drop during storage at 4.2 V, 4.4 V and 4.7 V at 40 °C and the best capacity retention during long-term cycling at 55 °C compared to cells with the other additives. Charge-hold-discharge cycling combined with simultaneous electrochemical impedance spectroscopy measurements showed that impedance growth in TMP-BF and TPPO-BF containing cells was faster than cells containing 2%PBF, suggesting that PBF is useful for impedance control at high voltages (>4.4 V). XPS analysis of the SEI films highlighted a specific reactivity of the PBF-derived SEI species that apparently hinders the degradation of both LiPF6 and solvent during formation and charge-hold-discharge cycling. The modified SEI films may explain the improved impedance, the smaller voltage drop during storage and the improved capacity retention during cycling of cells containing the PBF additive.

The occurrence and distribution of 14 organophosphate (OP) triesters and 5 diesters were investigated in sludge from eight sewage treatment plants (STPs) in Beijing, China, during 2008-2014. Tri(2-ethylhexyl) phosphate (TEHP) and tri-m-cresyl phosphate (TCrP) were the predominant triesters with the average concentration of 233-137 μg/kg, respectively. Also, the polar and hydrophilic trimethyl phosphate (TMP) and triethyl phosphate (TEP) were detected in 19% and 74% of sludge samples, respectively. Three of five diesters were detected in sludge samples, and di(2-ethylhexyl) phosphate (DEHP) revealed the highest average concentration of 96.0 μg/kg, followed by diphenyl phosphate (DPhP, 18.0 μg/kg). The levels of OP triesters in sludge varied with the compositions of the sewage and treatment capacity of STPs, as well as the adjacent sources. In comparison with that in the former years, relatively higher concentration of total OP triesters in sludge was observed in 2014, which is consistent with the rapid growth in consumption of these chemicals in China. Finally, environmental risk assessment indicated potential harmful effects of OP triesters on soil microorganisms after sludge landfill or fertilization.

The presented work was focused on the development of a new liquid chromatography-tandem quadrupole mass spectrometry method (LC-MS/MS) for the identification and quantification of organophosphates in lithium hexafluorophosphate (LiPF6)-based lithium ion battery electrolytes. The investigated electrolyte consists of 1 M LiPF6 dissolved in ethylene carbonate/ethyl methyl carbonate (50/50, wt%) and was treated electrochemically and thermally. For the electrochemical experiments, the cut-off potential in the half cells was held at 5.5 V for 72 h. The thermal degradation experiments were performed in aluminum vials at 95 °C for a period of 13 days. In the first part of this work, an already established gas chromatography-mass spectrometry (GC-MS) method for identification of dimethyl fluorophosphates (DMFP) and diethyl fluorophosphate (DEFP) was applied. In the second part, the LC-MS/MS method including determination of characteristic transitions in a product ion scan was developed. The developed method was applied for the identification of various analytes in the decomposed electrolytes. In addition, a possible formation of ionic and non-ionic OPs based on findings of this work and our previous reports is presented. In the third and final part, a quantification study of DMFP and DEFP was performed with a newly developed LC-MS/MS method and compared with results obtained by GC-MS. In addition, trimethyl phosphate (TMP) and triethyl phosphate (TEP) were quantified. These studies included the investigation of the suppression effects caused by the sample matrix during the application of the LC-MS/MS method.