Barium Stannate Research Articles

On the possibility of p-type doping in barium stannate

The combination of optical transparency and bipolar dopability in a single material would revolutionize modern opto-electronics. Of the materials known to be both p- and n-type dopable (such as SnO and CuInO2), none can satisfy the requirements for both p- and n-type transparent conducting applications. In the present work, perovskite BaSnO3 is investigated as a candidate material: its n-type properties are well characterized, with La-doping yielding degenerate conductivity and record electron mobility, while it has been suggested on a handful of occasions to be p-type dopable. Herein, group 1 metals Li, Na, and K and group 13 metals Al, Ga, and In are assessed as p-type acceptor defects in BaSnO3 using a hybrid density functional theory. It is found that while K and In can induce hole concentrations up to 1016 cm−3, the low energy oxygen vacancy pins the Fermi level in the bandgap and ultimately prevents metallic p-type conductivity being achieved in BaSnO3. Nevertheless, the predicted hole concentrations exceed experimentally reported values for K-doped BaSnO3, suggesting that the performance of a transparent p–n homo-junction made from this material could be significantly improved.

Description of electron mobilities in epitaxial lanthanum-doped barium stannate films: Influences of LO phonons, threading dislocation, and ionized donor defects

Lanthanum-doped barium stannate (La-doped BaSnO3 or LBSO) has attracted the attention of researchers and engineers because of its wide range of potential applications in electronic and optoelectronic devices. This is due to a combination of its exceptional room temperature (RT) mobility of 320 cm2 V−1 s−1 and high visible range transparency. However, epitaxial LBSO films made using strategic deposition techniques such as molecular beam epitaxy, pulsed laser deposition, and magnetron sputtering show comparatively low RT mobilities, between 24 and 183 cm2 V−1 s−1, and an accurate description of these RT mobilities is still sought. Herein, we provide the underlying scattering mechanisms related to longitudinal optical (LO) phonons, threading dislocation, and ionized donor defects to elucidate the RT mobilities in LBSO epitaxial films. It was found that the total mobility estimated using Matthiessen's rule provided strong quantitative agreement with experimental results. The large polaron mobility based on LO phonon scattering dominated the whole spectrum of electron concentrations in this system. It was an upper bound mobility, i.e., the mobility limit attained at 320 cm2 V−1 s−1. The calculated mobility associated with LO phonon and threading dislocation scatterings adequately verified the experimental results between 150 and 183 cm2 V−1 s−1. The predicted results for all three scattering types were predominant in experimental data at less than 150 cm2 V−1 s−1. These investigations deepen our understanding of mechanisms governing the charge transport scattering in epitaxial LBSO films and pave the way for the development of novel semiconductor thin films for use in electronic and optoelectronic devices.

Enhanced visible-light photocatalytic remediation of atrazine over CuAl2O4-modified BaSnO3 nanoplatelets synthesized by sol-gel route

Photocatalytic remediation of organic pollutants employing semiconducting nanocomposites is a capable, green, and feasible approach. In this work, the photocatalytic mineralization of emerging atrazine herbicide (AtZ) is realized utilizing sol-gel-prepared barium stannate (BaSnO3) nanoplatelets that are impregnated with copper aluminate (CuAl2O4) nanoparticles for the first time. The formed CuAl2O4/BaSnO3 p-n heterojunctions signified mesostructured texture with surface areas of 173–192 m2 g1 and 7.94 nm of pore diameter. The light harvesting in the visible regime is improved thanks to the controllable addition of CuAl2O4 at 15.0–20.0 wt% reducing the bandgap to 2.66 eV. The photocatalytic mineralization of AtZ has been achieved over 2.0 gL1 15% CuAl2O4/BaSnO3 at an initial rate of 20.0 µM min–1 within 40 min. Also, this optimized photocatalyst can be reused five times with 97% of its first-time use. The superb performance of CuAl2O4/BaSnO3 is attributed to the efficient p-n heterojunction formation and improved visible-light harvesting that allows superior charge transfer toward the photooxidation process.

Enhanced photoreduction of mercury (II) ions over MnCo2O4-modified wrinkled BaSnO3 nanosheets prepared by solvothermal method under visible light

Photocatalytic reduction of heavy metal ions utilizing nanostructured semiconductor photocatalysts is a promising ecological way, thanks to its simplicity and feasibility. In this article, the improved photoreduction of mercury (II) ions (Hg2+) is achieved over wrinkled barium stannate (BaSnO3) nanosheets modified by manganese cobaltate (MnCo2O4) nanoparticles. The MnCo2O4 was coupled to solvothermally-produced BaSnO3 at 4.0–16.0 wt% by impregnation. The MnCo2O4/BaSnO3 heterojunctions showed mesoporous surfaces with 133–150 m2 g1 of surface areas. The visible light harvesting is improved owing to bandgap reduction down to 2.31 eV for 9.0 wt% MnCo2O4-impregnated BaSnO3 compared to 2.99 eV for the bare BaSnO3. The complete photoreduction of 368.30 µM Hg2+ utilizing 9.0% MnCo2O4/BaSnO3 is achieved at a dosage of 2.4 gLẌ with a rate of 69.54 µM min–1 in 30 min. This optimized photocatalyst is also recyclable five times with 97% of its initial performance. The magnificent activity of MnCo2O4/BaSnO3 is accredited to the improved visible-light harvesting and efficient charge separation by the controllable impregnation of MnCo2O4.

Solvothermal-based synthesis of barium stannate nanosheets coupled with copper manganate nanoparticles for efficient photooxidation of tetracycline under visible light

Photocatalytic oxidation of antibiotic waste over semiconducting heterojunction photocatalysts is considered eco-friendly because it is simple and operates under light irradiation. In this work, we apply a solvothermal-based process for obtaining high surface area barium stannate (BaSnO3) nanosheets followed by adding 3.0–12.0 wt% of spinel copper manganate (CuMn2O4) nanoparticles to form n-n CuMn2O4/BaSnO3 heterojunction photocatalyst after calcination process. The CuMn2O4-supported BaSnO3 nanosheets exhibit mesostructure surfaces with a high surface area range of 133–150 m2g−1. Moreover, introducing CuMn2O4 to BaSnO3 shows a significant broadening in visible light absorption range due to bandgap reduction down to 2.78 eV in 9.0% CuMn2O4/BaSnO3 compared to 3.0 eV for pure BaSnO3. The produced CuMn2O4/BaSnO3 is used for photooxidation of tetracycline (TC) in water as emerging antibiotic waste under visible light. The photooxidation of TC exhibits the first-order reaction model. The specific dose of 9.0 wt% CuMn2O4/BaSnO3 at 2.4 gL−1 displays the highest-performed and recyclable photocatalyst for total oxidation of TC after 90 min. This sustainable photoactivity is attributed to the improved light harvesting and charges migration upon coupling between CuMn2O4 and BaSnO3.

Promoted photocatalytic H2 evolution over NiS/BaSnO3 nanocomposite photocatalyst prepared by modified sol-gel method

Barium stannate (BaSnO3) nanostructures have been synthesized by supercritical drying of its sol-gel-prepared seeds. Following this, Nickel sulfide nanoparticles (NiS) were impregnated with BaSnO3 at ratios of 3.0‒12.0 wt.% to produce NiS/BaSnO3 nanocomposite photocatalysts. Different characterization tools evaluated the formed nanostructures. The results revealed the positive impact of adding NiS for improving light harvesting and suppression of charge recombination. The produced heterostructures also were employed for H2 evolution in the water/glycerol system under visible light. The 9.0 wt.% NiS-impregnated BaSnO3 designated the lowest predicted bandgap of 2.36 eV with amended photoactivity in addition to the high surface area of 179 m2 g‒1. Likewise, the evolved H2 rate is improved by employing this heterostructure to 1.935 mmol g−1h−1 compared to 0.168 mmol g−1h−1 for the pristine BaSnO3. Moreover, the 2.0 gL−1 dose of 9% NiS/BaSnO3 revealed the promotion of H2 evolution to 2.902 mmol g−1h−1 and 97.5% regeneration ability within five cycles.

Promoted visible-light-driven oxidative desulfurization of thiophene over mesoporous PdO-incorporated BaSnO3 nanocomposites

An emerging method for removing sulfur-containing materials like thiophene, known as photocatalytic oxidative desulfurization, utilizes moderate temperatures and pressures without the use of H2 gas, unlike hydrodesulfurization. Here, we used a hydrothermal technique to produce Barium stannate nanoparticles (BaSnO3 NPs). A PdO/BaSnO3 photocatalyst was then fabricated by adding small amounts (0.5–2.0% wt) of PdO to mesoporous BaSnO3. After 150 min under illumination, the developed PdO/BaSnO3 photocatalyst showed complete thiophene photooxidative desulfurization and had excellent recyclability. The designed nanocomposite containing 2.0 wt% of PdO, displayed improved absorption of visible light with a bandgap reduction from 2.98 to 2.21 eV. Photoluminescence and photocurrent data of the developed photocatalysts demonstrated that the recombination of the photogenerated charge carriers was also whittled down. According to kinetic studies, the PdO content and the photocatalyst dose had a significant impact on the reaction rate which follows the pseudo-first-order model. Additionally, the mechanism of photooxidation of thiophene was discussed. This research will pave the way for the wide use of perovskite oxide photocatalysts to oxidize sulfur-containing materials under visible illumination.

Temperature-dependent dielectric measurements and structural properties of barium stannate (BaSnO3)

Cubic perovskite BaSnO3, synthesized by solid-state reaction method, was structurally characterized using temperature-dependent X-ray and Raman spectroscopy studies along with room temperature neutron diffraction analysis. Here, we report the effect of temperature on the structural parameters of BaSnO3 in correlation with dielectric properties. Sample homogeneity and elemental composition were studied by scanning electron microscopy and energy dispersive X-ray spectroscopy methods. The compound maintains cubic symmetry even at high temperatures and exhibits gradual increase in unit cell volume owing to thermal expansion. To understand high temperature phase transition, if any, and capacitance behavior, high temperature dielectric measurements were carried out. High value of dielectric constant was obtained at low frequencies as the temperature was increased, which may be due to the presence of oxygen vacancies or the lone-pair effect.

S-scheme AgVO3-decorated BaSnO3 heterojunction for efficient photoreduction of Mercury (II) ions under visible light

BackgroundHeavy metal waste has been slowly accumulating in water supplies due to the industry's current growth, posing a serious threat to the environment and all living things. MethodsIn this paper, we describe an unpretentious hydrothermal technique for forming barium stannate nanocrystals (BSO), which are then modified with different doses (3–12 wt.%) of AgVO3 (AVO). The structural, optical, and photocatalytic features of the resulted photocatalysts were positively impacted by the AVO loading, according to characterization studies. Significant findingThe decrease of the bandgap of BSO from 2.94 to 2.39 eV and an improvement in absorbing visible light are both confirmed by the AVO decorating of just 9.0 wt%. Additionally, under visible light, the ability of the as-prepared photocatalysts to reduce Hg2+ ions were evaluated. The complete photoreduction of Hg2+ ions over the 9% AVO/BSO nanocomposite were achieved at a higher kinetic rate constant (0.057 min−1) compared to pristine BSO NPs after 45 min of illumination. After being used five runs to reduce Hg2+ during visible illumination, the AVO/BSO heterojunctions demonstrated significant stability and outstanding photocatalytic practicability. And then, the Hg2+ photoreduction reaction's mechanism was explained. This study illustrates how modified BSO photocatalysts can be used in water remediation processes.

Mesostructured ellipsoidal capsules barium stannate based perovskite photocatalysts anchored PtO nanoparticles for hydrogen evolution

Background: The separation and transportation of photocarriers are considered significant factors in photocatalytic H2 evolution. Method: Mesoporous BaSnO3, with superior electron mobility with a large surface area, was chosen to integrate PtO nanoparticles (NPs) to obtain a highly effective photocatalytic system. PtO NPs (5–10 nm) are uniformly hosted with high crystallinity on the mesoporous BaSnO3 networks by impregnation-calcination approach. Significant Findings: TEM images of BaSnO3 exhibited ellipsoidal capsules with lengths of 200 ± 10 nm and a diameter of 50 nm. The construction PtO/BaSnO3 heterojunction system with better electron transport ability was modulated to achieve better photocatalytic ability than BaSnO3. The H2 evolution over 1.2% PtO/BaSnO3 nanocomposite was about 21,550 μmol·g−1 after 9 h visible illumination, while bare BaSnO3 was produced only 3750 μmol·g−1. The optimal 1.2% PtO/BaSnO3 nanocomposite revealed the largest H2 evolution, and it was promoted 5.75 times larger than BaSnO3. The H2 evolution rate over-optimized 1.2% PtO/BaSnO3 photocatalyst was about 2380 μmolg−1h−1, 6 times larger than that of bare BaSnO3 (397.37 μmolg−1h−1). The obtained PtO/BaSnO3 nanocomposites could facilitate the photoinduced electrons transfer from BaSnO3 to PtO, indicating the efficient photoinduced carriers separation for the enhanced H2 evolution rate. The PtO/BaSnO3 nanocomposite displayed high photostability and recyclability even after 45 h of illumination. This work provides a novel approach for perovskites with mesoporous structures and tunable bandgap with low PtO content utilized in energy applications and photocatalytic reactions.

Thermal and chemical expansion behavior of hydrated barium stannate materials

BaSnO3 is a relatively new family of proton-conducting materials, which are attractive for high-temperature applications, including protonic ceramic fuel cells and protonic ceramic electrolysis cells. In this work, we synthesized the BaSn1–xYxO3–δ (0 ≤ x ≤ 0.4) phases and provided their in-depth characterization utilizing high-temperature X-ray diffraction and dilatometry techniques to reveal the fundamental regularities in the variations of chemical and thermal strains depending on composition. It is found that chemical expansion/contraction effects become to be more important with increasing the Y-content. In particular, the weakly doped stannates exhibit predominantly thermal expansion, while the heavily doped stannates (especially, x = 0.4) display a notable chemical contribution. The mentioned effects are discussed in terms of the BaSn1–xYxO3–δ defect structure and its ability towards hydration and dehydration. This work therefore provides valuable data for the real application of the studied materials (in both powder and ceramic forms) as well as other pronounced proton-conducting electrolytes.

Synthesis, Characterization and Studies of Nanosized BaSnO3 and Its Poly (vinylalcohol) Nanocomposite Film

Synthesis of nanosized materials integrates the materials synthetic technology. Nanosized bimetallic oxides constitute class materials in concerned with its applications. The present work reports the synthesis of barium stannate (BaSnO3)nanopowder by self-propagating combustion reaction using polyvinyl alcohol (PVA) as a fuel. Initially basic oxides barium oxide (BaO) and tin oxide (SnO2) are also prepared by combustion route. Further barium stannate-PVA nanocomposite (BaSnO3-PVA) is prepared by dispersion of BaSnO3 material into PVA matrix using solvent casting method. Structural characterization of oxide and nanocomposite was studied by X-ray diffraction (XRD) tool and bonding nature by Fourier transfer infrared study (FT-IR) respectively. Thermal behavior of both the sample is well studied by thermo gravimetric analysis (TGA). Electrochemical study of the sample is carried out by cyclic voltammetry (CV) instrumentation. Varied morphology and particle size of the sample was analysed through Transmission electron microscope (TEM) tool.

Ionic and electronic transport of dense Y-doped barium stannate ceramics for high-temperature applications

The search for new oxide materials with pronounced proton transport is of great importance for the fabrication of electrochemical devices capable of realizing various energy conversion processes with high efficiency. The state-of-the-art proton-conducting oxides based on Ba(Ce,Zr)O3 have been proposed as the most promising electrolytes for such devices, although they suffer from a number of drawbacks. Here, we report an in-depth analysis of the transport properties of Y-doped barium stannates as relatively new proton-conducting compounds. In detail, the single-phase BaSn1–xYxO3–δ (0 ≤ x ≤ 0.4) ceramics were successfully prepared and their electrochemical properties were analysed using a number of characterization methods, including conductivity and thermo-EMF measurements depending on oxygen partial pressure as well as electrochemical impedance spectroscopy. The data obtained clearly indicate that the Y-doping degree affects the transport properties of BaSn1–xYxO3–δ. The weakly doped stannates (0 ≤ x ≤ 0.15) are identified as pronounced n- and p-type electron conductors, while the heavily doped stannates (0.2 ≤ x ≤ 0.4) exhibit a higher ionic conductivity and a wider electrolytic domain boundary, which allows them to be considered as new potential electrolytes with good grain boundary conductivity for application in both protonic ceramic fuel and electrolysis cells.

Exploration and study on the influence of Zinc substituted Barium Stannate (BaSnO3) nano powders for ammonia sensing applications

In the present work, we report the results of the gas sensing performance of ternary Barium Stannate (BaSnO3) semiconducting oxide material doped with zinc at the Barium site (Ba1-xZnxSnO3, where x = 0.0; 0.2; 0.4; 0.6; 0.8 & 1.0). The samples are synthesized using a facile hydrothermal technique. The X-Ray Diffraction technique revealed that the synthesized samples are cubic structures with a preferential orientation along the (110) plane. In the exploration of the Field Emission Scanning Electron Microscope (FESEM), a structural deformation is observed for the doped samples and the material compositional information is witnessed through the EDAX spectrum for all the samples. The optical absorption spectra are carried out using UV-DRS and the calculated bandgap values are decreased for the Zn doped samples approximately to 0.7 eV compared to pristine BSO. Among various test gases, all the interdigitated electrode materials exhibited a fast response to NH3 except 2B1-xZnxSnO3. Amidst these electrode materials (BZSO (0–10 wt%)), the 8BZSO exhibited good sensitivity to NH3 at 5 ppm at room temperature. The similar response, recovery time (the 40 s), and good cyclic repeatability of the 8BZSO electrode material clarify that this would be the most favourable electrode material for NH3 gas sensing.

Improved H2S sensitivity of nanosized BaSnO3 obtained by hydrogen peroxide assisted sol-gel processing

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 °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.

Evolution of the structure of MSnO3 (M = Ba, Sr) perovskites during hydrothermal synthesis and their photocatalytic activity.

The synthesis of barium and strontium stannates in the process of decomposition of hydrothermally obtained precursors has been investigated. It was found that endothermic weight loss during the synthesis of barium stannate occurs in two stages, whereas during the synthesis of strontium stannate it occurs in one stage. From the summary of the results of thermogravimetric analysis, X-ray diffraction, and Mössbauer spectroscopy, the composition and local structure of X-ray amorphous phases are proposed. It is shown that the improvement of the crystal structure of the perovskite phases of MSnO3 (M = Ba, Sr) and the symmetry of the local environment of 119Sn continues up to high temperatures (1250-1500 °C) and is associated with the elimination of defects in the anion sublattice. The photocatalytic activity of hydrothermal phases MSn(OH)6 and their thermolysis products has been studied and was found not to be directly related to the specific surface area of the photocatalysts. The degradation of rhodamine B (RhB) occurs during the "dark" stages of catalysis due to the interaction of the dye with reactive oxygen species (mainly singlet oxygen). At the first stage, the decomposition of the RhB photochromic system is observed, whereas at the final stage of bleaching the dye is deethylated.

The crucial role of defect structure in understanding the electrical properties of spark plasma sintered antimony doped barium stannate

The influence of structural defects in spark plasma sintered BaSn1-xSbxO3 (BSSO, x = 0.00 and 0.08) ceramic samples on their electrical properties was investigated in the temperature range of 300–4 K. X-ray photoelectron spectroscopy (XPS) revealed the presence of point defects, primarily oxygen vacancies (VO) and mixed oxidation states of tin (Sn2+/Sn4+) in both samples. As a result, the undoped BSSO sample exibited a non-standard semiconductor behavior, retaining its temperature-dependent resistivity. The electrical resistivity of the doped samples was two orders of magnitude lower than that of the undoped sample. The presence of structural defects such as VO, mixed oxidation states of the constituent elements, and significant amounts of O− species make the electrical resistivity of the doped sample constant in the temperature range of 300–70 K, indicating heavily-doped semiconductor behavior.

Accelerating electron transport in Eosin Y by bidentately bridging on BaSnO3 for noble-metal-free photocatalytic H2 production

The separation and transport of photogenerated carriers is regarded as a curial factor in photocatalytic H2 production. As known in solar cells and photoelectron-chemistry, to strengthen the electron conduction for effective utilization of carriers, the electron transport material (ETM) is widely applied. Herein, inspired by the function of ETM, we adopted barium stannate (BaSnO3, labeled as BSO) as an excellent ETM which had the merits of high electron mobility, suitable conduction band position and simple preparation, to adjust the carrier kinetics of dye Eosin Y (EY)-sensitized photocatalytic system. Detailly, the photocatalytic system with the spatial separation sites of photogenerated carriers excitation and water reduction reaction was elaborately constructed, that was, dye EY-sensitized BSO (EY/BSO) for photocatalytic H2 production. The photocatalytic H2-production rate of EY/BSO (257 μmol·h−1·gEY−1) in the absence of noble metals was 28.6 times higher than that of single EY (∼9 μmol·h−1·gEY−1) under visible-light irradiation. With systematic and comprehensive characterizations, the formed electron transport channel by the bidentate bridging of EY on BSO could accelerate the transfer of photogenerated electrons from EY to BSO, promoting the effective separation of photogenerated carriers for the enhanced photocatalytic performance. Moreover, the water reduction reaction for H2 production proceeded on the surface of BSO that acted as the H2-evolution cocatalyst, avoiding the use of high-cost noble metals. Furthermore, based on the well-proved ETM-based concept in the EY/BSO system, La-doped BaSnO3 (LBSO) with better electron transport ability was adopted to construct EY/LBSO system (344 μmol·h−1·gEY−1) which showed better photocatalytic activity than EY/BSO.

Investigation of n-type co-doping in barium stannate nanoparticles

Barium stannate (BaSnO3) has recently emerged as an ideal candidate for use as a transparent electrode, especially when appropriately doped. Whilst research has been conducted on the effects of using various elements to dope BaSnO3, to date there has been no systematic study into the role of two separate elements doping both sites at once. Here, were present an in-depth investigation into the optical and crystallographic effects of simultaneously doping the barium stannate crystal at both cationic sites. A wet chemical methodology to synthesize BaSnO3 nanoparticles that enables tunable doping with lanthanum (at the Ba site) and/or antimony (at the Sn site) is developed. Doping is validated via energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and absorption spectroscopy in the visible and near infrared range. Through high-resolution X-ray diffraction (XRD) and transmission electron microscopy (TEM) we assessed the effect of doping on the crystal size and strain, and then evaluated the role of each dopant in affecting the plasmonic properties of the BaSnO3 nanoparticles as a function of dopant concentration and annealing temperature. We show that doping across both sites results in less lattice strain, less defects, and overall larger particles, and through a systematic study we provide design rules to synthesize high-quality BaSnO3-based nanomaterials.

Ba2–xLaxSnO4+δ layered barium stannate materials: Synthesis, electronic transport, and chemical stability

The design and synthesis of new solid oxide materials are important areas in both fundamental and applied chemistry. In the present work, we consider weakly studied Ba2SnO4 layered materials for high-temperature applications. The Ba2–xLaxSnO4+δ (x = 0.05 and 0.1) samples were prepared according to the conventional solid-state synthesis method followed by sintering at 1150–1200 °C. Although a single-phase state was achieved for all the studied compositions, the decomposition of the layered phases into individual oxides (BaO, SnO2/SnO and La2O3) following their long-term storage even under ambient conditions can be explained in terms of their interactions with gas components (H2O and CO2). Nevertheless, the chemical stability of Ba2–xLaxSnO4+δ was slightly improved by La-doping. The electrical characterisation indicated that Ba2SnO4 at 700–900 °C is an n- and p-type conductor with negligible oxygen ionic conductivity. Ba2SnO4 thus represents a relevant research object for fundamental and applied sciences when solving issues with its unsatisfactory chemical stability.