Oxide Fluoride Research Articles

Theoretical process for the investigation of dielectric characteristics of F3NO as an alternative gas for SF6

To examine the possibility of using a gas molecule as an SF6 alternative gas, the insulation properties of the molecule must be estimated. In this work, we present a theoretical approach to calculate geometry parameters, electron scattering cross sections, and transport properties of nitrogen fluoride oxide (F3NO), which we have selected as an alternative to SF6. The molecular minimum structure of F3NO was optimized using the ɷB97X-D functional combined with the aug-cc-pVTZ basis set. Using this initial geometry obtained by the molecular structure calculation, the R-matrix calculation was done to obtain the elastic and momentum transfer cross section. The BE-f method was used for electronic excitation cross section. For the ionization cross section, the binary encounter Bethe method was used. From the calculated cross section data, the electron transport coefficients and reaction coefficients were calculated by solving the two-term approximated Boltzmann equation to investigate the discharge and insulation characteristics.

Self-Powered Wearable Breath Sensor Cum Nanogenerator Using AuNR-rGO-PVDF Nanocomposite

Breathing is the most important function of living being. It is well known that breath contains 90% humidity along with various gases and volatile organic compounds (VOCs). These gases are released during various metabolic activities in the body. These gases present in the breath can act as biomarkers to showcase healthiness or abnormalities in the body. Therefore, breath sensors are the need of time to detect diseases at early stages and in noninvasive way. Herein, we report, simple breath sensor using Au nanorods (AuNRs) and its nanocomposite with reduced graphene oxide (rGO) and polyvinylidene fluoride (PVDF). The nanocomposites system is designed in such a way that each component has its advantages for breath sensing. Here, AuNR being a good humidity sensitive material detects the breath efficiently. The <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula> phased PVDF being a very good ferroelectric material, contributes for voltage generation during sensing and enables the device to be self powered. The highly conducting rGO increases the sensitivity and voltage generation by facilitating the electron transport in the nanocomposite system. The nanocomposite was optimized with respect to PVDF, rGO and Au concentration. The as-synthesized materials were characterized by physiochemical characterization techniques such as field emission scanning electron microscopy (FESEM), X-ray diffraction analysis (XRD), UV-Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\beta $ </tex-math></inline-formula> phase formation of the PVDF was confirmed from the XRD peak at 20.41°. SEM results revealed that AuNR have length 15–20 nm and aspect ratio <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sim $ </tex-math></inline-formula> 3–4. Breath sensing tests were carried out for as synthesized nanocomposite material. The nanocomposite exhibited high sensitivity towards breath and generated the voltage of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\sim $ </tex-math></inline-formula> 0.7 V within 0.8 s.

Влияние продолжительности боромеднения на толщину диффузионного слоя и микротвердость углеродистых и легированных сталей

Introduction. Borocoppering is one of the methods of thermochemical treatment (TCT) aimed at forming diffusion layers with high physical and mechanical properties on the surface of carbon and alloy steels. The thickness of the diffusion layer is the most important characteristic of the TCT, which determines the depth of hardening. Consequently, the intensity and main characteristics of the TCT (layer thickness, alloying element concentration profile) depend on the process conditions (temperature, duration, and amount of alloying element). The purpose of this work is to determine the temperature-time parameters of diffusion borocoppering, which contribute to the formation of diffusion layers with a maximum thickness. The paper considers the results of surface hardening of carbon and alloy steels (for example, Steel 45 (0.45% C), Steel U10 (1.0% C), and 0.5C-Cr-Ni-Mn steel) by high-temperature soaking in powder mixtures containing boron and copper. Borocoppering was carried out in sealed containers with the powder mixture consisting of boron carbide, copper oxide, and sodium fluoride as an activator at a temperature of 950 °C for 3–5 h. The resulting specimens with a diffusion layer were examined using an optical microscope and a scanning electron microscope (SEM); the microhardness, elemental and phase composition of the layers were also determined, as well as the roughness of the obtained surfaces. Results and discussions. The microstructure of the obtained diffusion layers is studied; diagrams of the changes in the layers’ thickness and the microhardness distribution over the layers’ thickness are shown. It is established that with an increase in the soaking time from 3 to 5 h, the thickness of the diffusion layer increases from 120 to 170 μm on Steel 45 (0.45% C); from 110 to 155 µm on Steel U10 (1.0% C) and from 130 to 230 µm on 0.5C-Cr-Ni-Mn steel. A gradual decrease in the concentration of boron and copper along the layer thickness from 15–16% and 2–3% on the surface, respectively, to zero values at the boundary with the base metal is revealed. It is established that borocoppering to the formation of more thick boride layers on the surface of carbon and alloy steels compared to pure boriding. Moreover, an increase in the duration of soaking during the process contributes to the greatest increase in the thickness of the layer on 0.5C-Cr-Ni-Mn steel. A study of microgeometry is carried out, microtopographies and profilograms of specimens’ surfaces are shown before and after borocoppering. It is established that the roughness after borocoppering increases by 2-3 times compared to the initial one, and an increase in the duration of the process does not have a significant effect on the roughness.

Advances in the Study of Gel Polymer Electrolytes in Electrochromic Devices

The electrolytes in electrochromic devices (ECDs) serve as a conduction medium between electrodes and providing compensating ions for electrochromic reactions. Their characteristics directly affect the performance of electrochromic devices. Due to their ease of processing and encapsulation and high ionic conductivity, polymer gel electrolytes are widely used in electrochromic devices. As gel electrolyte polymers, polyethylene oxide (PEO), polymethyl methacrylate (PMMA), and polyvinylidene fluoride (PVDF) are reviewed according to their polymer matrix. Furthermore, future development trends in gel polymer electrolytes are discussed.

Polymer‐based separator for all‐solid‐state batteries produced by additive manufacturing

AbstractThe high demand for an efficient energy supply for various applications facilitates the development of innovative storage technologies like all‐solid‐state batteries in addition to novel production technologies. Compared to the conventional manufacturing process, additive manufacturing (AM) is a promising technology used for the rapid and cost‐effective production of battery components containing separators. However, AM technologies like laser‐based powder bed fusion of polymers (PBF‐LB/P) have been neglected so far. The present research aims to fill this research gap and outline a novel approach for processing polymers like polyethylene oxide (PEO) and polyvinylidene fluoride (PVDF) into separators using PBF‐LB/P. Optimal process parameters for manufacturing PVDF and PEO with PBF‐LB/P to generate homogeneous and dense layers represent the key findings of this paper and provide a deeper process understanding. The first proof of concept for producing separator layers by PBF‐LB/P in a scalable process is demonstrated as a result.

Magnetic field-assisted fabrication of quasi-bilayered, multi-responsive and patternable actuators.

Quasi-bilayered actuators composed of Fe3O4-decorated graphene oxide and polyvinylidene fluoride have been fabricated in a magnetic field. The actuators could stably respond to multiple stimuli including infrared light, acetone vapour and a magnetic field. The actuator is also patternable because of the magnetism-induced spatial distribution of fillers in the matrix.

DEVELOPMENT AND INVESTIGATION OF PROPERTIES OF MIXED CATALYSTS FOR VAPOR-PHASE HYDRATION OF ACETYLENE

In order to develop new catalysts for the synthesis of acetaldehyde by vapor-phase hydration of acetylene, new mono- and bifunctional catalysts based on cadmium, zinc, chromium, and iron compounds on supports were developed and their most important textural characteristics were studied. It was shown that zinc oxide and cadmium fluoride are bifunctional catalysts, in the presence of which acetaldehyde was synthesized with a yield of 69.0 — 70.0%. It has been established that the stability of their operation before regeneration exceeds more than 100 hours, i.e. 1.3 times more than industrial cadmium-calcium phosphate catalyst.

GLASSY FUNCTIONAL FILLERS OF GLASS IONOMER CEMENTS IN THE SrO–Al2O3–P2O5–SiO2–F SYSTEM

Based on glass in the SrO–Al2O3–P2O5–SiO2–F system, functional glass fillers for glass ionomer cements containing up to 13 wt. % fluorine were obtained. The high level of radiopacity of the filling material is due to the presence of the absorbing component of the glass filler - oxide and strontium fluoride, which are introduced into the glass together. The use of fusible fluorine-containing raw materials makes it possible to reduce the glass transition temperatures, which opens up prospects for the industrial development of the developed compositions at melting temperatures below 1500 °C. The value of the refractive index of glasses with a high fluorine content nD ~ 1.50 is more in line with the refractive index of the polymer matrix of glass ionomer cement, which ensures high aesthetic characteristics of the filling material. Samples of transparent filling glass ionomer cement with high compressive strength &gt; 100 MPa and hardening time of 5 min were obtained.

Evaluation of Dentin Remineralization with Zinc Oxide and Calcium Fluoride Nanoparticles - An In vitro Study.

Partially demineralized dentin is remineralizable when mineral ions are made available in the near vicinity. Nanoparticles (NPs) have wide applications in remineralization process. Zinc promotes remineralization and has a synergistic effect when combined with fluoride. Hence, zinc oxide and calcium fluoride NPs were considered for dentin remineralization. The aim of this study was to evaluate the remineralizing ability of zinc oxide and calcium fluoride NPs on demineralized dentin individually and in combined form. This was an in vitro study. Forty-eight dentin disks were prepared from the crowns of 12 extracted human molars and were allocated into four groups of 12 each, i.e., Group I - nano zinc oxide (nZnO), Group II - nano calcium fluoride (nCaF2), Group III - combined group (nZnO + nCaF2), and Group IV - artificial saliva (AS, control group). The specimens were demineralized with 37% phosphoric acid and placed in the respective remineralizing solutions for 24 h and 1 month. Calcium (Ca) and phosphorous (P) uptake was measured using energy-dispersive X-ray spectrometry, and structural changes were analyzed using scanning electron microscopy (SEM). One-way analysis of variance, Student's t-test, and post hoc Tukey's test were used for statistical analysis. At 1-month interval, all the groups showed an increase in Ca/P ratio, with highest being the combined group (4.24), followed by nCaF2 (3.30), nZnO (1.71), and AS (1.31) groups, and these differences were statistically significant (P = 0.000). On SEM analysis of dentinal samples at 1 month, depositions were evident in intertubular regions, wherein the highest deposits were observed in the nZnO group, followed by nZnO + nCaF2 and nCaF2 groups. Dentin samples subjected to remineralization with aqueous solutions of nZnO and nCaF2 showed an increase in calcium and phosphorous uptake and also dense granular depositions were evident in intertubular regions of dentin.

Combined Triboelectric and Piezoelectric Effect in ZnO/PVDF Hybrid-Based Fiber-Structured Nanogenerator with PDMS:Carbon Black Electrodes.

We report a fiber-structured hybrid nanogenerator wearable device fabricated on a single polyethylene terephthalate (PET) textile cylindrical substrate. The device can be described as a capacitor with inner and outer carbon-black-dispersed poly dimethyl siloxane (PDMS:Carbon black) electrodes, and zinc oxide and polyvinylidene fluoride (PVDF) as the dielectric medium between the electrodes. The compositional analysis in terms of X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy of the synthesized ZnO/PVDF has been measured and analyzed. The combined effect of triboelectricity between PDMS:Carbon black and PVDF, and piezoelectricity in a ZnO/PVDF hybrid, was investigated. Current–voltage characteristics were observed with varying load from 0–20 g, and resistance was observed to be decreased with load. Compared to earlier reports, there was a significant enhancement in voltage (≈5.1 V) and current (≈92.5 nA) at 10 g. Due to the introduction of interfacial polarization between PVDF and ZnO, the piezoelectric properties and pressure sensitivity of the hybrid ZnO/PVDF is enhanced. The hysterical behavior in the device’s response while measuring voltage and current with varying time shows the signature of the triboelectric effect between PVDF and ZnO, as well as PDMS:Carbon black and ZnO/PVDF layers. Reduction of triboelectric behavior was confirmed with increasing relaxation time. Because of the enhancement in piezoelectricity, fiber-structured nanogenerator (FNG) ZnO/PVDF proved to a potential candidate to be used for wearable computing devices, such as smart watches and sports bracelets.

In-Situ Resistance Optimization for ALD Nanocomposite Resistive Materials

Atomic layer deposition (ALD) made resistive nanocomposite materials can be used in many emerging applications such as charge draining layers for electron optic and MEMS devices, functional resistive layers in electron/ion amplifying microchannel plates (MCPs) which are used in photodetectors and mass spectrometry, HF resistance with tunable electrical conductivity coatings for stabilizing Li-ion battery cathode materials, selective solar absorbing coatings for concentrated solar power (CSP), and barrier and encapsulation coatings. Over the last decade, we have worked broadly on the research and development of resistive nanocomposite coatings. In this context, we have developed many nanocomposite materials with tunable resistance based on mixing conducting ALD metal and insulating ALD metal oxide or metal fluoride processes. These ALD nanocomposite materials show robust material performance in many of the applications listed above. Here we are particularly targeting a functional resistive coating that now commercially used for manufacturing large area ALD-MCPs. For this, there are two key topics that we are addressing a) Minimum thickness requirement for resistive coating which provides a stable targeted resistance behavior for MCPs, and b) Can we tune the temperature coefficient of resistance (TCR) of the ALD nanocomposite materials so that the ALD MCPs can operate over a wide temperature range without affecting their performance. To address these two topics, we have utilized in-situ resistance monitoring during the ALD nanocomposite process. With this method we have optimized resistive nanocomposite material ALD processes e.g. (M:Al2O3 where M= W and Mo) for MCPs and also targeted the desired TCR of the materials and achieved ultra-low TCR values. We believe these optimized coatings will reduce the ALD-MCP processing time substantially and enable ALD-MCPs and photodetectors to operate over a broader temperature range compared to existing ALD-MCPs.

Perfluoroalkyl-Functionalized Graphene Oxide as a Multifunctional Additive for Promoting the Energetic Performance of Aluminum.

Aluminum (Al) is a widely used metal fuel for energetic applications ranging from space propulsion and exploration, and materials processing, to power generation for nano- and microdevices due to its high energy density and earth abundance. Recently, the ignition and combustion performance of Al particles were found to be improved by graphene-based additives, such as graphene oxide (GO) and graphene fluoride (GF), as their reactions provide heat to accelerate Al oxidation, gas to reduce particle agglomeration, and fluorine-containing species to remove Al2O3. However, GF is not only expensive but also hydrophobic with poor mixing compatibility with Al particles. Herein, we report a multifunctional graphene-based additive for Al combustion, i.e., perfluoroalkyl-functionalized graphene oxide (CFGO), which integrates the benefits of GO and GF in one material. We compared the effects of CFGO to GO and GF on the ignition and combustion properties of nAl particles using thermogravimetric analysis, differential scanning calorimetry, temperature-jump ignition), Xe flash ignition, and constant-volume combustion test. These experiments confirm that CFGO generates fluorine-containing species, heat, and gases, which collectively lower the ignition threshold, augment the energy release rate, and reduce the combustion product agglomeration of nanosized Al particles, outperforming both GO and GF as additives. This work shows the great potential of using multifunctionalized graphene as an integrated additive for enhancing the ignition and combustion of metals.

Chemically graft aminated GO onto dehydro-fluorinated PVDF for preparation of homogenous DF-PVDF/GO-NH2 ultrafiltration membrane with high permeability and antifouling performance

Blending of hydrophilic nanoparticles into the PVDF ultrafiltration membrane has been proved to be an effective and simple way to improve the hydrophilicity and the anti-fouling performance. However, due to the heterogeneous nature, aggregation or leakage of the hydrophilic nanoparticles usually happened at higher concentration which would further go against for improving the filtration performance. Here, aminated graphene oxide (GO-NH2) and dehydro-fluorination polyvinylidene fluoride (DF-PVDF) were synthesized, and GO-NH2 was chemically grafted on DF-PVDF via Michael addition reaction. The resultant DF-PVDF/GO-NH2 membrane was obtained, and the structure, hydrophilicity, and the antifouling performance of DF-PVDF/GO-NH2 membrane are systematically investigated. As a result, the GO-NH2 grafted membranes (Mg membranes) exhibited uniform and smooth surfaces with numerous visible pores and higher porosity compared to GO co-blending membranes (Mb membranes) and the original PVDF membrane. Besides, the Mg membranes possessed lower water contact angle (48°± 1.0°), higher water flux (355 L/m2 h) and better flux recovery ratio (up to 88%), showing better hydrophilicity and anti-fouling performance together with better mechanical properties. Static adsorption experiment also indicated the better anti-fouling performance of Mg membranes due to the uniformly dispersion of hydrophilic GO and the strong electrostatic repulsion between negatively charged GO and BSA.

Assessment of thermodynamic parameters of the plasma chemical process for magnesium oxide production

This work are presented the calculation results of thermodynamic parameters of the reaction of magnesium fluoride decomposition by ionized water vapor with the formation of solid magnesium oxide and gaseous hydrogen fluoride at atmospheric pressure in the temperature range from room temperature to 2800◦C . The calculation of the thermodynamic parameters was carried out with the Reaction Equations software module of scientific programs HSCChemistry package. Thermodynamic analysis of magnesium fluoride MgF2 was carried out on a thermogravimetric analyzer TGA/DSC2. The thermodynamic parameters results are in good agreement with the results of thermogravimetric analysis. There were determined the optimum conditions for plasma-chemical processing of magnesium fluoride.

The Correlation Between Crystal Phase and Acidity in Nickel Doped Zinc Fluoride Solid

Nickel-doped zinc fluoride (Zn 1‑x Ni x F 2 ) with x= 0; 0.025; 0.050; 0.075; 0.100 and 0.150 were synthesized from zinc acetate as precursors. Solid materials were prepared by the fluorolytic sol gel method. The resulting solid materials were characterized by XRD and FTIR. The XRD characterization of the samples showed that there were characteristic peaks of zinc fluoride, zinc oxide and zinc hydrogen fluoride. The IR characterization spectrum showed the presence of Zn-F, Zn-O and -OH bonds in the samples. Pyridine adsorbed FTIR technique explains that the material has Lewis and Brønsted acidity. The acidity site in the solid were influenced by the Zn-O and Ni-O bonds in the catalyst.

Constructing rapid water vapor transport channels within mixed matrix membranes based on two-dimensional mesoporous nanosheets

Membrane technology is an effective strategy for gas dehumidification and fuel cell humidification. In this study, cerium fluoride oxide (F-Ce) two-dimensional (2D) mesoporous nanosheets and their composite with 1-ethyl-3-methylimidazolium dicyanamide ([Emim][DCA]) ionic liquids (ILs) (IL@F-Ce) are introduced as fillers into polyether block amide (PEBAX® 1074) to fabricate mixed matrix membranes (MMMs). The slit-shaped mesoporous structure of the nanosheets facilitates the construction of water vapor rapid transport channels in MMMs. The permeability and selectivity of water vapor for MMMs loaded with F-Ce nanosheets are greatly improved, and the performance of MMMs loaded with IL@F-Ce nanosheets are much better than the former. Particularly, the MMM with IL@F-Ce content of 4 wt.% achieves the highest H2O permeability of 4.53 × 105 Barrer, which is more than twice that of the pure PEBAX membrane, and the selectivity is increased by 83%. Thus, the MMMs based on 2D mesoporous nanosheets have considerable potential application in industrial-scale dehydration and humidification processes.

Plasma sprayed fluoride and zinc doped hydroxyapatite coated titanium for load-bearing implants

Titanium (Ti) alloys show excellent fatigue and corrosion resistance, high strength to weight ratio, and no toxicity; however, poor osseointegration ability of Ti may lead to implant loosening in vivo. Plasma spraying of hydroxyapatite [HA, Ca10 (PO4)6 (OH)2] coating on Ti surfaces is commercially used to enhance osseointegration and the long-term stability of these implants. The biological properties of HA can be improved with the addition of both cationic and anionic dopants, such as zinc ions (Zn2+) and fluoride (F−). However, the hygroscopic nature of fluoride restricts its utilization in the radiofrequency (RF) plasma spray process. In addition, the amount of doping needs to be optimized to ensure cytocompatibility. We have fabricated zinc and fluoride doped HA-coated Ti6Al4V (Ti64) to mitigate these challenges using compositional and parametric optimizations. The RF induction plasma spraying method is utilized to prepare the coatings. Multiple parametric optimizations with amplitude and frequency during the processing result in coating thicknesses between 80 and 145 μm. No adverse effects on the adhesion properties of the coating are noticed because of doping. The antibacterial efficacy of each composition is tested against S. aureus for 24, 48, and 72 h, and showed that the addition of zinc oxide and calcium fluoride to HA leads to nearly 70 % higher antibacterial efficacy than pure HA-coated samples. The addition of osteogenic Zn2+and F− leads to 1.5 times higher osteoblast viability for the doped samples than pure HA-coated samples after 7-days of cell culture. Zn2+ and F− doped HA-coated Ti64 with simultaneous improvements in anti-bacterial efficacy and in vitro biocompatibility can find application in load-bearing implants, particularly in revision surgeries and immune-compromised patients.

Hybrid lithium salts regulated solid polymer electrolyte for high-temperature lithium metal battery

Herein, a blending solid polymer electrolyte that composed of polyethylene oxide (PEO) and polyvinylidene fluoride (PVDF) was prepared by a simple solution-casting method, and the effect of different lithium salts on electrochemical performance at high operating temperature was studied. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) tests were performed to reveal the physical properties of obtained electrolytes, and electrochemical measurements demonstrate that a mixture of different Li salts with appropriate ratio in PEO/PVDF (1:1) shows a better property at 60 ​°C. The assembled LiFePO4||Li solid cells can reach a specific capacity of 160 mAh g−1 with an ionic conductivity of 9.12 ​× ​10−5 ​S ​cm−1. Contributed to the adopt of dual-salts, a high tLi+ value of 0.66 was obtained. It can be seen that the addition of rigid polymer into a soft matrix can effectively enhance the mechanical strength of solid polymer electrolytes to resist the dimensional loss at high temperature, and the mixture Li salts can improve the electrochemical properties. As a result, this work can provide a practical solution for assembly high safety solid Li metal battery for high temperature.

Polymeric Dental Nanomaterials: Antimicrobial Action.

This review aims to describe and critically analyze studies published over the past four years on the application of polymeric dental nanomaterials as antimicrobial materials in various fields of dentistry. Nanoparticles are promising antimicrobial additives to restoration materials. According to published data, composites based on silver nanoparticles, zinc(II), titanium(IV), magnesium(II), and copper(II) oxide nanoparticles, chitosan nanoparticles, calcium phosphate or fluoride nanoparticles, and nanodiamonds can be used in dental therapy and endodontics. Composites with nanoparticles of hydroxyapatite and bioactive glass proved to be of low efficiency for application in these fields. The materials applicable in orthodontics include nanodiamonds, silver nanoparticles, titanium(IV) and zinc(II) oxide nanoparticles, bioactive glass, and yttrium(III) fluoride nanoparticles. Composites of silver nanoparticles and zinc(II) oxide nanoparticles are used in periodontics, and nanodiamonds and silver, chitosan, and titanium(IV) oxide nanoparticles are employed in dental implantology and dental prosthetics. Composites based on titanium(IV) oxide can also be utilized in maxillofacial surgery to manufacture prostheses. Composites with copper(II) oxide nanoparticles and halloysite nanotubes are promising materials in the field of denture prosthetics. Composites with calcium(II) fluoride or phosphate nanoparticles can be used in therapeutic dentistry for tooth restoration.

La2FSeTaO4: lanthanum fluoride selenide oxotantalate or lanthanum fluoride oxoselenotantalate?

Abstract Following up the recently reported example La3F2Se2TaO4, colorless needle-shaped single crystals of the new compound La2FSeTaO4 were obtained as an unexpected by-product from solid-state reactions between lanthanum metal, lanthanum trifluoride, lanthanum sesquioxide and selenium in a sodium-chloride flux designed to yield lanthanum oxide fluoride selenides. Silica-jacketed tantalum capsules served as reaction containers at 850 °C, but an undesired activation of the metal tubes led to the formation of a new oxotantalate. La2FSeTaO4 crystallizes orthorhombically in the space group Pnma with the lattice parameters a = 1146.51(6), b = 395.16(2) and c = 1281.32(7) pm for Z = 4. The crystallographically unique Ta5+ cations are surrounded by five oxygen atoms as square pyramids [TaO5]5–, which share trans-oriented vertices (d(Ta–O4) = 202 pm, 2×) to form straight ∞ 1 Ta O 1 , 2 , 3 3 / 1 t O 4 2 / 2 v 3 − ${}_{\infty }^{1}\left\{{\left[\text{Ta}{\left.\text{O}1,2,3\right.}_{3/1}^{t}{\left.\text{O}4\right.}_{2/2}^{v}\right]}^{3-}\right\}$ chains propagating along [010] with isotactically aligned tips (d(Ta–O1) = 183 pm). Embedded into a matrix of lanthanum fluoride selenide according to ∞ 3 La 2 FSe 3 + ${}_{\infty }^{3}\left\{{\left[{\text{La}}_{2}\text{FSe}\right]}^{3+}\right\}$ (d(La–F) = 236–244 pm, d(La–Se) = 312–318 pm), which consists of two different La3+ cations as well as singular F− and Se2− anions, via La–O contacts (d(La–O) = 247–274 pm), the coordination number of the La3+ cation towards the anions F−, O2− and Se2–amounts to nine with tricapped trigonal prisms or capped square antiprisms as coordination polyhedra models. The tantalum cation has a distant contact with a Se2− anion (d(Ta⋯Se) = 317 pm), not efficiently counting to its first coordination sphere, but completing it to a quasi-octahedron.