Trivalent Bismuth Research Articles

Trivalent bismuth xanthates: Synthesis and characterization

Trivalent bismuth xanthates: Synthesis and characterization

Development of Reactivity for Organobismuth (III, V) Toward Sulfur-Containing Compounds

Organobismuth compounds have been used in various areas of science, like biology and organic synthesis, because they are normally nontoxic and exhibit unique properties. Bismuth induces metallothionein production and is known to exhibit thiophilicity. However, few reports on the reactions between bismuth and sulfur compounds exist. This article reviews studies on the reactivity of bismuth (III and V) with sulfur compounds. A simple approach for the reaction of azole-2-thiones, which contains a heterocyclic ring, with triaryl bismuthines in the presence of a copper catalyst affords the S-arylated coupling product. When a palladium catalyst is used instead of a copper catalyst, desulfinative C-C bond formation occurs. These reactions indicate that trivalent bismuth compounds can be used as novel aryl sources. Triphenylbismuth dichloride, an organobismuth (V) reagent, successfully promotes the cyclodesulfurization of thioureas within short reaction times under mild conditions. The reaction affords N-substituted benzoxazol-2-amines in excellent yields. Tafamidis, a drug used to treat transthyretin amyloidosis, can be synthesized using this reaction.

TeO[formula omitted]–BaO–Bi[formula omitted]O[formula omitted] tellurite optical glasses I. - Glass formation, structural, thermal and optical properties

The present study investigates the glass-forming ability (GFA), structural, thermal, and optical properties of the TeO2–BaO–Bi2O3 (TeBaBi) glass system, focusing on the mutual substitution trends of its constituent compounds. Prepared glasses were synthesized by the melt-quenching method at 900 °C and the GFA was extended by chemical compositions with lower TeO2 (55–85 mol.%) and higher Bi2O3 (5–15 mol.%) content via optimization of the synthesis process. The introduction of BaO and/or Bi2O3 results in the increase of the glass transition temperature (Tg≈327–384°C), molar volume (Vg≈28.9–33.1cm3mol−1) and optical basicity (OB≈0.97–1.03). Prepared TeBaBi glasses exhibit satisfactory thermal stability and wide spectral region of optical transparency from 0.4–6.5 μm with observed narrowing of optical window with higher TeO2 content. Compositional evolution of Tg may be described for the TeBaBi glasses using multilinear regression analysis with high correlation (r≥0.995) across the whole GFA region. The structure of studied TeBaBi glasses was investigated by Raman scattering and directly compared to the TeO2–ZnO–BaO (TZB) glass system prepared and characterized under identical conditions. Structural analysis revealed a similar degree of internal glass structure transformation regardless of whether a divalent zinc cation or trivalent bismuth cation is present.

Steering Geometric Reconstruction of Bismuth with Accelerated Dynamics for CO2 Electroreduction.

Bismuth-based materials have emerged as promising catalysts in the electrocatalytic reduction of CO2 to formate. However, the reasons for the reconstruction of Bi-based precursors to form bismuth nanosheets are still puzzling, especially the formation of defective bismuth sites. Herein, we prepare bismuth nanosheets with vacancy-rich defects (V-Bi NS) by rapidly reconstructing Bi19Cl3S27 under negative potential. Theoretical analysis reveals that the introduction of chlorine induces the generation of intrinsic electric field in the precursor, thereby increasing the electron transfer rate and further promoting the metallization of trivalent bismuth. Meanwhile, experimental tests verify that Bi19Cl3S27 has a faster reconstruction rate than Bi2S3. The formed V-Bi NS exhibits up to 96 % HCOO- Faraday efficiency and 400 mA cm-2 HCOO- partial current densities, and its electrochemical active surface area normalized formate current density and yield are 2.2 times higher than those of intact bismuth nanosheets (I-Bi NS). Density functional theory calculations indicate that bismuth vacancies with electron-rich aggregation reduce the activation energy of CO2 to *CO2 - radicals and stabilize the adsorption of the key intermediate *OCHO, thus facilitating the reaction kinetics of formate production.

Steering Geometric Reconstruction of Bismuth with Accelerated Dynamics for CO2 Electroreduction

AbstractBismuth‐based materials have emerged as promising catalysts in the electrocatalytic reduction of CO2 to formate. However, the reasons for the reconstruction of Bi‐based precursors to form bismuth nanosheets are still puzzling, especially the formation of defective bismuth sites. Herein, we prepare bismuth nanosheets with vacancy‐rich defects (V‐Bi NS) by rapidly reconstructing Bi19Cl3S27 under negative potential. Theoretical analysis reveals that the introduction of chlorine induces the generation of intrinsic electric field in the precursor, thereby increasing the electron transfer rate and further promoting the metallization of trivalent bismuth. Meanwhile, experimental tests verify that Bi19Cl3S27 has a faster reconstruction rate than Bi2S3. The formed V‐Bi NS exhibits up to 96 % HCOO− Faraday efficiency and 400 mA cm−2 HCOO− partial current densities, and its electrochemical active surface area normalized formate current density and yield are 2.2 times higher than those of intact bismuth nanosheets (I‐Bi NS). Density functional theory calculations indicate that bismuth vacancies with electron‐rich aggregation reduce the activation energy of CO2 to *CO2− radicals and stabilize the adsorption of the key intermediate *OCHO, thus facilitating the reaction kinetics of formate production.

A Comprehensive Review on Non‐Trivalent Bismuth‐Based Materials: Structure, Synthesis, and Strategies for Improving Photocatalytic Performance

Bi‐based semiconducting materials have received tremendous attention due to their availability, non/low toxicity, ecological friendship, rich chemical forms, and good visible‐light‐driven photocatalytic performance. As compared to the commonly investigated trivalent bismuth (Bi(III))‐based photocatalysts, non‐trivalent bismuth‐based materials (NTBBMs), such as BiO2−x, Bi2O4−x, Bi4O7, NaBiO3, and so on, exhibit excellent visible‐light‐ and even full‐spectrum‐driven photocatalytic activity as they hold narrow bandgap, suitable positions of conduction band and valence band, and relatively redox‐sensitive structures. In this review, it is attempted to summarize the recent progress in the preparation, microstructures, and modification strategies of various NTBBMs‐based photocatalysts. At the end, the advantages and disadvantages of NTBBMs‐based photocatalysts and future perspectives are presented.

Cationic substitution engineering induced Multi-Color light emitting of bismuth in Tantalate used for WLED

Revealing and predicting the photoluminescence behavior of trivalent bismuth activated phosphors is very important for exploiting high-quality photoluminescent materials and modulating their luminescence properties, since it commonly performs multi-type electronic transitions. In this work, the chosen matrix of Gd3TaO7, which contains only one highly symmetrical cationic crystallographic site, is favorable for analyzing luminescence behavior of Bi3+ ions, and Bi3+-activated Gd3TaO7 can emit bright green light under the near-ultraviolet (NUV) light or low voltage electron beam excitation. The cationic substitution engineering of rare earths Ln (Ln = Lu, Y and La) replacing Gd3+ ions was carried out for further regulation of spectra, and multi-color light emitting was successfully realized. However, their unusual photoluminescence properties bring a novel comprehension for the photoluminescence behavior of Bi3+ ions in this system. For well rationalizing this phenomenon, the first-principles calculation was carried out for revealing their electronic structure, combined with their geometry optimization. The results indicate multi factors have contribution in modulating the luminescence behavior of Bi3+ ions, especially the interaction between 3P1 state, metal-to-metal charge transfer state and Bi-Bi dimers. The result is favorable for us to exactly adjust the luminescence properties of Bi3+ ions.

Energy transfer and photoluminescence properties of CaYGaO4:Bi3+,Tb3+ phosphors

Trivalent bismuth and trivalent terbium ions doped CaYGaO4 were prepared. The crystal structure, phase purity, photoluminescence, decay curves, and emission spectra under various temperatures were investigated. The six-coordinate Ca2+ and Y3+ ions are occupied by Bi3+ ions, while Tb3+ ions take up the six-coordinate Y3+ ions in the CaYGaO4:Bi3+,Tb3+ phosphor. The emissions of trivalent bismuth (3P1 → 1S0) and trivalent terbium ions (5D4 → 7F5) excited by 320 nm were observed. The analysis of spectra and decay curves demonstrated that Bi3+ could transfer energy to Tb3+ via electric dipole-quadrupole interaction. By altering the concentration of trivalent terbium ions, the emitting color of phosphor was tuned from blue to green. The temperature sensing property of CaYGaO4:Bi3+,Tb3+ was described, and its relative sensitivity at 303 K achieves a maximum of 0.61% K−1. According to the results, CaYGaO4:Bi3+,Tb3+ is a potential material for color tunable emission and temperature sensing.

Accelerating solid-liquid interfacial hole transfer kinetics through designed flower-like trivalent bismuth crystallite island for photoelectrochemical application

Hematite (Fe2O3) is an appealing photoanode material for photoelectrochemical application due to its suitable band-gap. However, the serious electron-hole recombination of hematite results in the photocurrent density generated is lower than the theoretical value. In this work, we loaded flower-like trivalent bismuth crystallite islands onto nano Fe2O3 electrodes to improve photoelectrochemical application. The trivalent bismuth ions decorated hematite photoanode demonstrates excellent photocurrent density, rapid water oxidation kinetics, and remarkable bulk separation efficiency. Mott-Schottky results indicate that surface-treated hematite showed increased carrier density and enhanced uptrend band bending. Furthermore, the trivalent bismuth ions accelerate hole capture through Bi(III)/Bi(V) exchange, reducing the recombination of oxygen-related holes with surface trapping sites. Under simulated sunlight irradiation, the photocurrent density at 1.23 (vs. RHE) exhibits fourfold enhancement that of hematite film. This work demonstrates a new possibility that Bi(III) compounds, in a passivation-like form, can effectively improve carrier transport on the surface of hematite photoanodes.

Recent Progress and Challenges of Bismuth‐Based Halide Perovskites for Emerging Optoelectronic Applications

AbstractRecently, metal halide perovskites have attracted extensive attentions owing to their superior optoelectronic properties in various device applications, such as solar cells, photodetectors, light‐emitting diodes, lasing, photocatalysis, etc. Up to now, the state‐of‐the‐art developments of perovskite‐based devices are most using the lead‐halide perovskite system. However, the presence of lead (Pb) in these devices, which is insidious bioaccumulative hazard to human bodies, and a poor stability against light, heat, and humidity hamper their practical applications and future commercialization. Therefore, the scientific community is searching for low‐toxicity and environmental‐friendly lead‐free perovskite‐type materials as a back‐up strategy. Among the possible Pb‐substitution strategies, the trivalent bismuth cation (Bi3+) possesses the same electronic configuration as Pb2+, and some emerging Bi‐based perovskites and derivatives are experimentally characterized, which exhibit comparable optoelectronic properties to the Pb‐based perovskites. In this review, a comprehensive overview of currently explored Bi‐based halide perovskites is reported, with an emphasis on their synthesis methods, structural diversity, photophysical properties, and their current and potential applications in various optoelectronic categories. Finally, this review is finished with a critical outlook into the current challenges and development prospects of Bi‐based halide perovskites toward the versatile optoelectronic applications.

Bismuth and Vanadium-Substituted Yttrium Phosphates for Cool Coating Applications.

Luminescent yttrium phosphate is engineered into an environmentally benign near infrared (NIR) reflective yellow pigment by the substitution of bismuth and vanadium metals in the host lattice. A series of YP(1-x)V x O4 (x = 0, 0.05, 0.1, 0.15, 0.2, and 0.4), Y(1-y)Bi y PO4 (y = 0.1 and 0.3), and Y(1-y)Bi y P(1-x)V x O4 (x = y = 0.2, 0.4, and 0.6) were prepared by the precipitation method. Secondary phase was noticed at x = 0.2 and y = 0.2 while substituting vanadium and bismuth, respectively, due to high ionic radii of the dopant ions. Co substitution of vanadium and bismuth in the YPO4 lattice enhanced both NIR reflectance and yellow color of all the fabricated materials. XPS spectra proved the presence of trivalent bismuth and pentavalent vanadium in Y0.4Bi0.6P0.4V0.6O4. Due to the substitution effect, a more defined morphology was noticed, which enhanced the scattering co-efficient of the fabricated materials; hence, the NIR reflectance of the materials was increased from 68% (YPO4) to 83% (Y0.4Bi0.6P0.4V0.6O4). Chemical and thermal stability test of Y0.4Bi0.6P0.4V0.6O4 confirmed the color and strength of the designed pigment. With good yellow hue (b* = +56.06), high NIR solar reflectance (R* = 83%), and good stability, Y0.4Bi0.6P0.4V0.6O4 can act as an environmentally benign cool yellow pigment.

Charge Transfer-Triggered Bi3+Near-Infrared Emission in Y2Ti2O7for Dual-Mode Temperature Sensing

Trivalent bismuth is a popular main group ion showing versatile luminescent behaviors in a broad spectral range from ultraviolet to visible, but barely in the near-infrared (NIR) region. In this study, we have observed unexpected NIR emission at ∼744 nm in a Bi3+-doped pyrochlore, Y2Ti2O7 (YTOB). Our first-principles electronic structure calculation and analysis of the Bi local structure via extended X-ray absorption fine structure indicate that only Bi3+ species appears in YTOB and it has a similar local environment to that of Y3+. The NIR emission is assigned to a Ti4+ → Bi3+ metal-to-metal charge transfer process. Moreover, we have demonstrated dual-mode luminescence thermometry based on the luminescence intensity ratio (LIR) and lifetime (τ) in 0.5% Bi3+ and 0.5% Pr3+ co-doped Y2Ti2O7 (YTOB0.5P0.5). It exhibits high thermometric sensitivity simultaneously in the cryogenic temperature range from 78 to 298 K based on τ of the NIR emission of Bi3+ at 748 nm and in the temperature range of 278-378 K based on the LIR of Bi3+ to Pr3+ emissions (I748/I615). As a novel LIR-τ dual-mode thermometric material over a wide temperature range, the maximum relative sensitivities of the YTOB0.5P0.5 reach 3.53% K-1 at 298 K from the τ mode and 3.52% K-1 at 318 K based on the LIR mode. The dual-mode luminescence thermometry with high responsivity from our Bi3+-based pyrochlore Y2Ti2O7 phosphor opens a new avenue for more luminescent materials toward multi-mode thermometry applied in complex temperature-sensing conditions.

Ammonium escorted chloride chemistry in stabilizing aqueous chloride ion battery

The blue ocean has attracted great expectations since it can provide sustainable and green energies. We propose and demonstrate a feasible strategy for a novel seawater-based chloride ion battery (CIB). Moreover, a new approach has been proposed to synthetically improve the reaction kinetics on both electrodes in CIB by introducing ammonium ions (NH4+) to the aqueous NaCl electrolyte. In particular, a seawater-based CIB has been developed with an initial discharge specific capacity of 123.7 mAh g−1 at a specific charge current 500 mA g−1 with a stable cyclability and excellent rate capability. The superior electrochemical performance of the CIB can be contributed to the Janus effect on promoting Cl− capture/release from both electrodes, hence enhancing AgCl/Ag conversion and more electrons transferred from trivalent bismuth to low valence state.

Interactions in ternary bismuth-containing molybdate systems M<sub>2</sub>MoO<sub>4</sub>-Bi<sub>2</sub>(MoO<sub>4</sub>)<sub>3</sub>-Zr(MoO<sub>4</sub>)<sub>2</sub> in the subsolidus region

A fundamental problem in materials science consists in establishing a relationship between the chemical composition, structure, and properties of materials. This issue can be solved through the study of multicomponent systems and the directed synthesis of promising compounds. Of practical interest here are active dielectrics that are based on complex oxide compounds, specifically molybdates. Among complex molybdates and tungstates, ternary caged molybdates of the following structural types are of greatest importance: nasicon, perovskite, langbeinite, etc. Due to their widely varying elemental and quantitative compositions, such molybdates are convenient models for structural and chemical design, as well as the establishment of “composition–structure– properties” genetic relationships. Bismuth-containing complex molybdate systems exhibit the formation of phases having ferro-piezoelectric, ionic, and other properties. In this work, the Rb2MoO4–Bi2(MoO4)3–Zr(MoO4)2 ter nary salt system was studied for the first time using the method of intersecting sections in the subsolidus region (450–650 ℃). To this end, quasibinary sections were identified; triangulation was performed. Ternary molybdates Rb5BiZr(MoO4)6 and Rb2BiZr2(MoO4)6,5 were formed in the system using a ceramic technology. These compounds are isostructural to the previously obtained REE molybdates (M5LnZr(MoO4)6) but contain trivalent bismuth instead of rare earth elements. The structure of Rb5BiZr(MoO4)6 was adjusted via the Rietveld refinement technique using the TOPAS 4.2 software package. The ternary molybdate crystallizes in a trigonal system, with the following unit cell parameters of the R`3c space group: a = 10.7756(2) and c = 39.0464(7) Å. According to the studies of thermal properties exhibited by M5BiZr(MoO4)6, these ternary molybdates undergo the first-order phase transition in the temperature range of 450–600 ºC. The IR and Raman spectra of M5BiZr(MoO4)6 reveal the crystallization of ternary molybdates in the R`3c space group. The conducted comparative characterization of M2MoO4–Bi2(MoO4)3–Zr(MoO4)2 phase diagrams suggests that the phase equilibria of these systems depend on the nature of molybdates of monovalent elements.

Peptide–Bismuth Bicycles: In Situ Access to Stable Constrained Peptides with Superior Bioactivity

AbstractConstrained peptides are promising next‐generation therapeutics. We report here a fundamentally new strategy for the facile generation of bicyclic peptides using linear precursor peptides with three cysteine residues and a non‐toxic trivalent bismuth(III) salt. Peptide–bismuth bicycles form instantaneously at physiological pH, are stable in aqueous solution for many weeks, and much more resistant to proteolysis than their linear precursors. The strategy allows the in situ generation of bicyclic ligands for biochemical screening assays. We demonstrate this for two screening campaigns targeting the proteases from Zika and West Nile viruses, revealing a new lead compound that displayed inhibition constants of 23 and 150 nM, respectively. Bicyclic peptides are up to 130 times more active and 19 times more proteolytically stable than their linear analogs without bismuth.

Peptide-Bismuth Bicycles: In Situ Access to Stable Constrained Peptides with Superior Bioactivity.

Constrained peptides are promising next-generation therapeutics. We report here a fundamentally new strategy for the facile generation of bicyclic peptides using linear precursor peptides with three cysteine residues and a non-toxic trivalent bismuth(III) salt. Peptide-bismuth bicycles form instantaneously at physiological pH, are stable in aqueous solution for many weeks, and much more resistant to proteolysis than their linear precursors. The strategy allows the in situ generation of bicyclic ligands for biochemical screening assays. We demonstrate this for two screening campaigns targeting the proteases from Zika and West Nile viruses, revealing a new lead compound that displayed inhibition constants of 23 and 150 nM, respectively. Bicyclic peptides are up to 130 times more active and 19 times more proteolytically stable than their linear analogs without bismuth.

A Comprehensive Potentiometric Study of the Tartrate Complexes of Trivalent Arsenic, Antimony, and Bismuth in Aqueous Solution.

The tartrate complexes of trivalent arsenic, antimony, and bismuth were studied potentiometrically. The existing, fragmentary data on the antimony/l-(+)-tartrate system were confirmed. Nine complexes of arsenic and bismuth with optically active, racemic, and meso-tartrate, as well as complexes of antimony with meso-tartrate, were newly identified, and their formation constants computed. Difficulties arising from the poor stability of the arsenic complexes and precipitation in the Sb(III)/meso-tartrate system were overcome by titrating at very high concentrations [As(III) systems] and using an auxiliary ligand [Sb(III) in the presence of catechol]. All data were obtained at 25.0 °C and at constant ionic strength [0.1 mol L-1 for Sb(III) and Bi(III) complexes and 1 mol L-1 for As(III) complexes]. Speciation diagrams of all systems at millimolar concentrations were computed on the basis of the newly obtained constants and the results discussed.

Bismuth activated blue phosphor with high absorption efficiency for white LEDs

Trivalent bismuth (Bi3+) activated blue-emitting materials have attracted considerable attention because they effectively avoid the reabsorption demerits compared to traditional rare earth activators. Unfortunately, these materials are often plagued by mismatch to the near-ultraviolet (n-UV) chip and short blue emission peak as well as low n-UV absorption efficiency. In this work, we successfully designed a blue-emitting phosphor SrZnSO:Bi3+ with a wide n-UV excitation band ranging from 310 to 400 nm and an ideal blue emission band centered at 460 nm. Furthermore, SrZnSO:0.03Bi3+ phosphor exhibits an extraordinary absorption efficiency of 73.21% ascribed to the intense absorption of the matrix and Bi3+ in the n-UV region. The relationship between the excitation peak position of Bi3+-related phosphors and the size of the polyhedron were also summarized. A white light-emitting diode (WLED) was fabricated using a 370 nm n-UV chip, the composition-optimized sample SrZnSO:0.03Bi3+ and the commercial phosphors. Interestingly, the temperature-sensitive luminescence behavior is beneficial to the performance improvement of the WLED. The WLED demonstrates a warm white light whose Commission Internationale de L′Eclairage (CIE) coordinates are (0.3817, 0.3885), outstanding color rendering index of 93.4 and low correlated color temperature of 4051 K at current of 80 mA. The study suggests that SrZnSO:Bi3+ blue emitting phosphor has great potential in LED-based applications. Also inspires researchers to explore Bi3+-related phosphors with low energy excitation band and high absorption efficiency to develop high-quality n-UV pumped WLEDs.

Formamidinium containing tetra cation organic–inorganic hybrid perovskite solar cell

ABX3 perovskites offer the advantage of manipulating its properties by introducing multiple cations in B-site. Over the years, researchers used mixed B-site perovskites in oxide electronics to tune their electrical, magnetic properties. Here we used the triple cations at B-site in formamidinium based organometallic halide perovskite solar cell (PSC) in order to improve its degradation behavior with respect to heat and moisture. We synthesized halide based two hybrid perovskites viz., formamidinium sodium bismuth lead iodide [NH2CHNH2(Na0.25Bi0.25)Pb0.5I3] and formamidinium potassium bismuth lead iodide [NH2CHNH2(K0.25Bi0.25)Pb0.5I3] using solution chemistry. In order to decrease the content of toxic lead in these perovskites, trivalent bismuth was incorporated in the Pb-site. Monovalent sodium and potassium were used to maintain the charge neutrality of B-site, which has the formal valence of + 2 in these ABI3 type perovskites. Both of these perovskites showed reasonable optical band gaps with good charge carrier lifetime suggesting it as potential candidates for solar energy conversion and provisionally we achieved power conversion efficiency η = 0.52%. Moreover, superior thermal and moisture stability in these perovskites were observed in periodical structural and spectral analysis carried out by XRD, UV–Vis spectroscopy, time-correlated single photon counting (TCSPC) over the period of one month. Furthermore, ultrafast carrier dynamics in these perovskites were unraveled using femtosecond transient absorption studies. Our transient absorption kinetics data suggested more auger recombination and faster free electron-hole recombination process in FKBPI compared to FNBPI, which corroborates well with better energy conversion efficiency obtained in FNBPI based solar cell.

High Lewis Acidity at Planar, Trivalent, and Neutral Bismuth Centers

Geometric perturbation away from classical structures can engender unusual frontier MO situations leading to high Lewis acidity. Recently we reported a T-shaped bismuth triamide, which exhibited pl...