Tantalum Metal Research Articles

Short and medium range order in the rapidly solidified metallic liquid Ta: Atomic packing, connection modes, and pressure effect

In this study, molecular dynamics (MD) simulations were utilized to explore the Short and Medium-Range Order (MRO) in the rapidly solidified metallic liquid tantalum (Ta). Radial distribution function (RDF) and Voronoi tessellation analysis (VTA) techniques were employed to thoroughly explore the effect of pressure on the connectivity and structural properties at the Short-Range Order (SRO) and MRO levels. Our findings indicate that, at a quenching rate of 1013 K s-1, glassy states are achieved at or below 20 GPa, while crystalline phases emerge at 25 GPa. VTA analysis indicates a significant alteration in the local structure of glassy Ta with increasing pressure. Specifically, the fraction of icosahedral-like clusters decreases while the fraction of crystal-like clusters rises notably.Furthermore, we highlight that icosahedral-like clusters strongly tend to form 3-atom connection mode, while crystal-like clusters prefer 2-atom and 4-atom connection modes. Notably, icosahedral-like clusters are identified as the primary contributors to the emergence of the left sub-peak in the second peak of the RDF. In contrast, all cluster types contribute to the appearance of the right sub-peak.

Progress in the Application of Porous Tantalum Metal in Hip Joint Surgery.

Porous tantalum metal is a new orthopedic implant material made of tantalum metal that has been processed by porous treatment. This material has various advantages, including high hardness, good ductility, good biocompatibility, and strong bone integration ability. Porous tantalum metal has performed well in clinical application, demonstrating excellent medium- to long-term curative effects. The use of implant products made of porous tantalum metal, such as porous tantalum rods, porous tantalum hip prostheses, and porous tantalum augments (MAs), is gradually increasing in the clinical application of hip surgery, and these products have achieved excellent therapeutic effects in the middle and late stages of various hip diseases. In recent years, the combined application of porous tantalum metal and three-dimenional (3D) printing technology to create personalized 3D-printed porous tantalum metal has led to new development directions for the treatment of complex hip joint surgical diseases. This review presents a summary of the application of porous tantalum metal in hip surgery in recent years, including clinical treatment effects and existing problems. In addition, the prospect of progress in this field is promoted.

Ethanol processable inorganic-organic hybrid hole transporting layers enabled 20.12% efficiency organic solar cells.

In this study, a high-performance inorganic-organic hybrid hole transporting layer (HTL) was developed using ethanol-soluble alkoxide precursors and a self-assembled monolayer (SAM). Three metal oxides-vanadium oxide (VOx), niobium oxide (Nb2O5), and tantalum oxide (Ta2O5)-were synthesized through successive low-temperature (100 °C) thermal annealing (TA) and UV-ozone (UVO) treatments of their respective precursors: vanadium oxytriethoxide (EtO-V), niobium ethoxide (EtO-Nb), and tantalum ethoxide (EtO-Ta). Among these, the Nb2O5 film exhibited excellent transmittance, a high work function, and good conductivity, along with a more compact and uniform structure featuring fewer interfacial defects, which facilitated efficient charge extraction and transport. Furthermore, the deposition of a SAM of (2-(9H-carbazol-9-yl)ethyl)phosphonic acid (2PACz) on top of Nb2O5 further passivated defects, enhancing interfacial contact with the photoactive layer. The resulting inorganic-organic hybrid HTL of Nb2O5/2PACz demonstrated excellent compatibility with various photoactive blends, achieving impressive power conversion efficiencies of 19.44%, 19.18%, and 20.12% for the PM6:L8-BO, PM6:BTP-eC9, and D18:BTP-eC9 based organic solar cells, respectively. 20.12% is the best performance for bulk heterojunction organic solar cells with binary components as the photoactive layer.

Получение композиционных материалов при аддитивном производстве

The main possibilities of obtaining new composite materials are presented. Due to the high dynamics of thermal deformation processes in the molten bath of a thin layer of the grown part, we obtain a new material structure from immiscible components. Another direction of obtaining a new composite material in the growing process is the reinforcement of the matrix with high-strength elements, which can be present, including in the form of a solid phase under melting and crystallization of the material. This allows predicting in advance new qualitative properties of the grown part - increased strength, weight reduction, etc. Additive technology is being developed for growing parts and products made of tungsten, molybdenum, tantalum, niobium and other hard-melting metals that are poorly treated through mechanical methods. In this case, heating is used within growing process. The successful application of additive technologies is used in medicine in the manufacture of implants made of molybdenum, tantalum and their alloys, which have high biocompatibility and no toxic property. It becomes possible to manufacture an implant grown according to a specific model for a given individual. The main directions of the additive manufacturing development are the creation of more productive complexes and the expansion of construction materials powders range, used when forming new composite materials in the growing process.

Controlled synthesis of tantalum-based solid solution and exploration of electrochemical properties as soluble anode for molten salt electrolysis

Metal oxycarbide solid solution possesses an extensive potential applications due to its remarkable physical features. In this paper, TaCxO1-x solid solution is successively and controllably synthesized by carbothermal reduction of Ta2O5. Based on the thermodynamic calculation, the possible reactions under different conditions in the carbothermal reduction process were analyzed, which provides theoretical guidance for controllable regulation and optimization of carbon thermal reduction process. The effects of carbon content, sintering temperature, and holding time on the synthesis of TaCxO1-x solid solution were investigated and the ideal process parameters for the synthesis of single-phase solid solution were identified. A single-phase solid solution with a carbon‑oxygen ratio close to 1:1 can be created as a soluble anode if the synthesis temperature is 1500 °C, the holding period is 6 h, and the molar ratio of C/Ta is 3.42. Moreover, the process feasibility of preparing metal tantalum by electrolysis of tantalum-based soluble anode is discussed, which provides a new method for metal tantalum preparation.

P1-xTa8+xN13 (x=0.1-0.15): A Phosphorus Tantalum Nitride Featuring Mixed-Valent Tantalum and P/Ta Disorder Visualized by Scanning Transmission Electron Microscopy.

We report on the synthesis, crystal, and electronic structure, as well as the magnetic, and electric properties of the phosphorus-containing tantalum nitride P1-xTa8+xN13 (x=0.1-0.15). A high-pressure high-temperature reaction (8 GPa, 1400 °C) of Ta3N5 and P3N5 with NH4F as a mineralizing agent yields the compound in the form of black, rod-shaped crystals. Single-crystal X-ray structure elucidation (space group C2/m (no. 12), a=16.202(3), b=2.9155(4), c=11.089(2) Å, β=126.698(7)°, Z=2) shows a network of face- and edge-sharing Ta-centered polyhedra that contains small vacant channels and PN6 octahedra strands. Atomic resolution transmission electron microscopy reveals an unusual P/Ta disorder. Mixed-valent tantalum atoms exhibit interatomic distances similar to those in metallic tantalum, however, the electrical resistivity is quite high in the order of 101 Ω cm. The density of states and the electron localization function indicate localized electrons in both covalent and ionic bonds between P/Ta and N atoms, combined with less localized electrons that do not contribute to interatomic bonds.

Microwave-assisted alkaline fusion followed by water-leaching for the selective extraction of the refractory metals tungsten, niobium and tantalum from low-grade ores and tailings

The refractory metals tungsten, tantalum and niobium are considered critical raw materials in Europe. Diversifying the supply of such materials, for instance by recovering refractory metals from local low-grade ore materials could reduce their supply risks. However, the extraction processes require to be efficient with a low energy and material consumption and a minimal environmental impact. In this work, microwave (MW) assisted alkaline fusion was explored to extract tungsten from scheelite containing ore materials with different grades (high to very low) and tantalum and niobium from a columbite-tantalite [(Fe,Mn)(Nb,Ta)2O6] concentrate. During the fusion process scheelite was converted into soluble alkali tungstate salts [Na2WO4, K2WO4 and/or K3Na(WO4)2] and the reaction temperature could be lowered to 150–200 °C by fusion with a low-melting eutectic alkali salt system of an 1:1 (m/m) NaOH:KOH mixture. The application of MW-assisted heating allowed for fast and volumetric heating, thereby lowering reaction times to 10 min – 30 min. After fusion, tungsten was extracted by a simple water leaching step leading to extraction efficiencies ranging from 77 % to 97 %. Noteworthily, also P, S and As, which all form soluble oxyanions were extracted from the studied materials. Extraction of niobium and tantalum was also achieved though MW-assisted alkaline fusion as an alternative to acidic fluorine-based hydrometallurgical processes. MW-assisted heating allowed for a fast conversion of the (Fe,Mn)(Nb,Ta)2O6 into alkali tantalate and niobate salts. Under optimal conditions, MW-assisted fusion with KOH (salt:sample = 3:1 (m/m)) at 400 °C for 10 min leached ca. 74 %–88 % of tantalum and 77 %–86 % of niobium into water (L/S=10) at 40 °C for 120 min, while the main matrix elements Mn and Fe displayed limited dissolution (<4%). Due to the low solubility of sodium tantalate and niobate salts in water, MW-assisted alkaline fusion in an eutectic NaOH:KOH mixture followed by water leaching was not efficient.

Biomechanical study of three-dimensional printed filler block design in open wedge high tibial osteotomy

The use of a filling block can improve the initial stability of the fixation plate in the open wedge high tibial osteotomy (OWHTO), and promote bone healing. However, the biomechanical effects of filling block structures and materials on OWHTO remain unclear. OWHTO anatomical filling block model was designed and built. The finite element analysis method was adopted to study the influence of six filling block structure designs and four different materials on the stress of the fixed plate, tibia, screw, and filling block, and the micro-displacement at the wedge gap of the OWHTO fixation system. After the filling block was introduced in the OWHTO, the maximum von Mises stress of the fixation plate was reduced by more than 30%, the maximum von Mises stress of the tibia decreased by more than 15%, and the lateral hinge decreased by 81%. When the filling block was designed to be filled in the posterior position of the wedge gap, the maximum von Mises stress of the fixation system was 97.8 MPa, which was smaller than other filling methods. The minimum micro-displacement of osteotomy space was -2.9 μm, which was larger than that of other filling methods. Compared with titanium alloy and tantalum metal materials, porous hydroxyapatite material could obtain larger micro-displacement in the osteotomy cavity, which is conducive to stimulating bone healing. The results demonstrate that OWHTO with a filling block can better balance the stress distribution of the fixation system, and a better fixation effect can be obtained by using a filling block filled in the posterior position. Porous HA used as the material of the filling block can obtain a better bone healing effect.

Nature of Metal‐Metal Bond in Group‐V Dinuclear Metallaborane Compounds: Open‐Shell – Open‐Shell Vs Closed‐Shell – Closed‐Shell Interaction

The investigation of metal‐metal bonding is interesting due to the captivating structural features, unique chemical reactivity and physical properties of this class of complexes. The bonding situation in the metallaboranes [(Cp*)2M2(B2H6)2] of group‐V elements (M) in the +3 oxidation state [M = V (1), Ta (2)] was investigated by the DFT, NBO, QTAIM calculations and further with Energy Decomposition Analyses coupled with Natural Orbital for Chemical Valence (EDA‐NOCV). Even though the metallaboranes are isostructural, the nature of metal‐metal bonding interaction was found to be different, showing open‐shell ‐ open‐shell interaction for vanadium while closed‐shell – closed‐shell interaction between two tantalum atoms. The EDA‐NOCV analyses suggest that TaIII‐TaIII bonding interactions are stronger than those of divanadaborane analogue, having an intrinsic interaction energy of ‐247.6 kcal/mol (2), and the V‐V bond has an interaction energy of ‐192.5 kcal/mol (1). The analyses indicate that the strength of the metal‐metal bond becomes stronger as the metal becomes heavier. This is due to the higher contribution from electrostatic stabilization energy. The pairwise orbital analysis of the metal‐metal bond denotes significant dative‐interaction between two tantalum metals, contributing 52.6% (2) to total orbital interaction energy. The electron‐sharing interaction energy has been computed to be 44.3% for 1.

P1–xTa8+xN13 (x = 0.1–0.15): A Phosphorus Tantalum Nitride Featuring Mixed‐Valent Tantalum and P/Ta Disorder Visualized by Scanning Transmission Electron Microscopy

We report on the synthesis, crystal, and electronic structure, as well as the magnetic, and electric properties of the phosphorus‐containing tantalum nitride P1–xTa8+xN13 (x = 0.1–0.15). A high‐pressure high‐temperature reaction (8 GPa, 1400 °C) of Ta3N5 and P3N5 with NH4F as a mineralizing agent yields the compound in the form of black, rod‐shaped crystals. Single‐crystal X‐ray structure elucidation (space group C2/m (no. 12), a = 16.202(3), b = 2.9155(4), c = 11.089(2) Å, β = 126.698(7)°, Z = 2) shows a network of face‐ and edge‐sharing Ta‐centered polyhedra that contains small vacant channels and PN6 octahedra strands. Atomic resolution transmission electron microscopy reveals an unusual P/Ta disorder. Mixed‐valent tantalum atoms exhibit interatomic distances similar to those in metallic tantalum, however, the electrical resistivity is quite high in the order of 10‑1 Ω cm. The density of states and the electron localization function indicate localized electrons in both covalent and ionic bonds between P/Ta and N atoms, combined with less localized electrons that do not contribute to interatomic bonds.

Strain effect on TaSe2/Te2 monolayer as adsorption substrate in lithium–sulfur battery

Lithium-sulfur (Li–S) batteries, with their high theoretical specific capacity and energy density, are considered a promising alternative to current energy storage technologies. However, their practical application is hindered by the polysulfide shuttle effect, which leads to capacity fade and reduced coulombic efficiency. In this study we employs density functional theory (DFT) to explore the use of two-dimensional (2D) metallic transition metal dichalcogenides (TMDs), tantalum diselenide (TaSe2) and tantalum ditelluride (TaTe2), as anchoring materials for lithium polysulfides (LiPSs). Our findings reveal that these TMD monolayers exhibit a balanced binding affinity towards LiPSs, ranging from 1.20ev to 3.34eV (TaSe2) and from 2.35ev to 3.74eV (TaTe2). Notably, the decomposition barriers for Li2S on TaSe2 and TaTe2 are significantly lower than those of bulk Li2S with a value of 1.62eV and 1.54eV, suggesting these materials can facilitate rapid charge-discharge processes. The introduction of strain, simulating the expansion during lithiation, demonstrates that these monolayers maintain their adsorption capabilities, a crucial attribute for practical applications, with a increased decomposition barriers of 2.4eV(TaSe2) and 2.51eV(TaTe2). The catalytic activity of these monolayers for the sulfur reduction reaction (SRR) was evaluated, showing a spontaneous conversion mechanism for lithium-sulfur clusters, which is expected to enhance the overall performance of Li–S batteries. This study presents TaSe2 and TaTe2 as innovative and promising candidates for advanced Li–S battery applications, offering a perspective in addressing the critical challenges associated with the polysulfide shuttle effect.

Hydrogenation and dehydrogenation behaviors of tantalum under different conditions

The hydrogenation behaviors of tantalum metal and the dehydrogenation behaviors of tantalum hydride powder have been studied in this paper. The results of hydrogenation show that the tantalum ingot is easy to form a barrier layer on its surface during hydrogenation, which can be broken by increasing the pressure of hydrogen and using hydrogenation-dehydrogenation-hydrogenation (H-De-H) process at the same time. Finally, tantalum hydride powder with hydrogen content of 0.427 wt % was obtained. The dehydrogenation results show that TaH0.1 and Ta phases begin to appear at 500 °C under vacuum condition, and complete dehydrogenation can be achieved at 600 °C for 1 h. Under the condition of hydrogen atmosphere, the presence of H2 has an inhibitory effect on the dehydrogenation reaction, and it is most obvious when the temperature is 700 °C.

Phase and Composition Engineering of Self-Intercalated 2D Metallic Tantalum Sulfide for Second-Harmonic Generation.

Self-intercalation in two-dimensional (2D) materials is significant, as it offers a versatile approach to modify material properties, enabling the creation of interesting functional materials, which is essential in advancing applications across various fields. Here, we define ic-2D materials as covalently bonded compounds that result from the self-intercalation of a metal into layered 2D compounds. However, precisely growing ic-2D materials with controllable phases and self-intercalation concentrations to fully exploit the applications in the ic-2D family remains a great challenge. Herein, we demonstrated the controlled synthesis of self-intercalated H-phase and T-phase Ta1+xS2 via a temperature-driven chemical vapor deposition (CVD) approach with a viable intercalation concentration spanning from 10% to 58%. Atomic-resolution scanning transmission electron microscopy-annular dark field imaging demonstrated that the self-intercalated Ta atoms occupy the octahedral vacancies located at the van der Waals gap. The nonperiodic Ta atoms break the centrosymmetry structure and Fermi surface properties of intrinsic TaS2. Therefore, ic-2D T-phase Ta1+xS2 consistently exhibit a spontaneous nonlinear optical (NLO) effect regardless of the sample thickness and self-intercalation concentrations. Our results propose an approach to activate the NLO response of centrosymmetric 2D materials, achieving the modulation of a wide range of optoelectronic properties via nonperiodic self-intercalation in the ic-2D family.

Improving the Quality of Tantalum Cylindrical Deep-Drawn Part Formation Using Different Lubricating Media-Coated Dies

Lubrication is one of the key factors to improve metal-forming quality. In the process of deep drawing, seizing tumors easily occur on the contact surfaces between the tantalum metal and the mold, which greatly affects the forming quality of the deep-drawn parts. Quality-forming quality problems that occur during the deep drawing of tantalum metal are studied from the perspective of lubrication in this paper. Three lubrication media, caster oil, PE (polyethylene) film, and DLC (Diamond Like Carbon) film, were adopted in the deep drawing of tantalum cylindrical cups. A universal testing machine and microscope were used to investigate the effect of lubrication media on the limit-drawing ratio, maximum forming force, and surface topography quality during the deep drawing process of the tantalum sheet. The results reveal that the lubrication of the PE film and DLC film can greatly improve the forming quality of the tantalum metal sheet, in which the DLC film has higher wear resistance and lower friction coefficient and can be used as the lubricating medium in the industrial forming process of tantalum deep-drawn parts.

Hydrometallurgical assessment of oxides of Nb, Ta, Th and U from Ethiopian tantalite ore

Tantalite ore is the main source of the metals niobium (Nb) and tantalum (Ta). Today, the needs for these economic and irreplaceable Nb, and Ta metals are becoming imperative for the technological world, to meet the demand, a lot of research is needed to ore reserves, extraction methodology and simplified refining processes should be in plethora. This study focuses on the Ethiopian tantalite ore located south of the Neoproterozoic Adola belt of the rare element Kenticha pegmatite deposit (global source of tantalite). Successive beneficiation of pegmatite ore results in a highest dissolution of 60.83 wt% of Ta2O5 with 4.58 wt% of Nb2O5 including the removal of U, Th, Ti, Fe and Si, resulting in a percentage low weight, which allows transporting ore concentrates. The concentrated ore is leached with a mixture of binary acids HF and H2SO4 with 6:1 ratio at temperatures from 100 to 400 °C. The filtered solution was extracted with MIBK then, precipitated with ammonium solution. The hydrometallurgy of Nb and Ta oxides is affected by leaching temperature and the presence of radioactive oxides of U and Th. Elemental analysis and surface topography were studied using SEM/EDS, revealing the highest percentage composition of Nb and Ta oxides at 200 °C of leaching temperature. Comparatively, the compositions of U and Th showed higher amounts at the leaching temperatures of 150 and 200 °C, and when the temperature reached about 350 and 400 °C, the percentage composition of U and Th became very low, the economic metals Nb and Ta were completely leached. The stability of the precipitated samples was analyzed using TGA-DTA and found to be thermally stable, and not contain significant moisture at each temperature studied. Studies for recovery of Ta, Nb, U and Th from Kenticha tantalite are required.

The Influence of Topologically Close-Packed Clusters on the Solidification Pathway of Metallic Tantalum Liquid Under High Pressure

The Influence of Topologically Close-Packed Clusters on the Solidification Pathway of Metallic Tantalum Liquid Under High Pressure

Design of efficient thermophotovoltaic system based on meta-material narrow-band emitter for space power supply

Photovoltaic technology has been widely used in spacecraft power supply, but its efficiency is difficult to be greatly improved by Shockley-Queisser limitation. The thermophotovoltaic technology can convert solar radiation energy or high temperature combustion energy into radiation energy with reshaped spectrum for direct photovoltaic power generation. In this study, a meta-material structure composed of metal tantalum, Ta, and dielectric SiO2 is innovatively proposed for shaping narrowband radiation. The results show that the optimized spectral emittance peak of narrowband emitters reaches 0.9998. Narrowband emitter has advantages at high temperatures above 1000 K. The thermophotovoltaic efficiency of InGaAsSb cell and tandem Si/InGaAsSb cells can reach more than 41.67% and 46.26%, respectively. It is significantly higher than published thermophotovoltaic system with broadband emitter. This study demonstrates the notable advantages and potential of narrowband emitter for spectrum reshaping, which provides an important reference for future spacecraft power supply as well as space solar power generation.

Synergetic treatment of waste tantalum capacitors and polyvinyl chloride by subcritical water: Tantalum recovery, benzoic acid production and dechlorination

The rapid upgrading of electronic products led to the generation of a great deal of waste tantalum capacitors (WTCs). The recovery of WTCs is of great interest due to the high-value metal tantalum and resin materials. However, it is difficult to separate/recover the materials from WTCs because of the special structure and composition. Polyvinyl chloride (PVC) waste with high level of chlorine could result in severe corrosion and emission of chlorinated pollutants in the conventional disposal process. In this study, a synergetic and high-efficiency treatment of WTCs and PVC by subcritical water (SubCW) process was developed based on the interaction of the two kinds of wastes. The interaction between WTCs and PVC in SubCW could significantly reduce the treatment temperature and shorten the reaction time for recovering high-purity metal tantalum from WTCs, and it could also markedly improve the dechlorination efficiency (DE) of PVC. The optimized conditions for the synergetic treatment of WTCs and PVC were 325 ℃, 30 min, solid-to-liquid ratio of 1:5 g/mL, and PVC-to-WTCs ratio of 6:1 g/g. The resin conversion efficiency (RCE) of WTCs and the DE of PVC could reach 100% and 97.39% under the optimized conditions. The HCl released from PVC in SubCW could significantly promote the acid-catalytic hydrolysis of resin materials in WTCs and resulted in the production of abundant phenol/phenol derivates. In turn, hydroxyl functional group of phenol/phenol derivates could enhance the dechlorination of PVC by promoting the hydroxyl substitution reaction pathway. High level of benzoic acid (72.52%) could be obtained from the interaction between the decomposition products of WTCs and PVC by radical and oxidation reactions. The SubCW synergetic process developed in this study provided a high-efficiency and low-energy strategy for metal tantalum recovery, benzoic acid production, and dechlorination from WTCs and PVC wastes.

Tantalum Oxide Thin Films Sputter-Deposited by Oxygen Gas Pulsing

Tantalum oxide thin films are deposited by DC reactive magnetron sputtering from a tantalum metallic target and argon + oxygen. The oxygen gas is pulsed during the deposition with a constant pulsing period T = 10 s, whereas the introduction time of the reactive gas, namely the tON injection time, is systematically changed from 0 to 100% of T. Therefore, composition of as-deposited TaOx films is continuously changed from pure metallic tantalum to the over-stoichiometric Ta2O5 material. Films adopt the body-centered cubic structure (metallic Ta) for the lowest tON injection time values (oxygen stoichiometry x &lt; 1.0) and become amorphous for the longest ones. It is shown that the tON injection time is a key parameter to deposit either homogeneous tantalum oxides, or periodic Ta/TaOx multilayers with alternations close to 3 nm. Optical transmittance in the visible region of the film/glass substrate system and electrical conductivity vs. temperature both exhibit a gradual evolution from metallic (σ300K = 8.17 × 105 S m−1 with an opaque behavior) to semiconducting (σ300K = 1.97 × 103 S m−1 with a semi-transparent transmittance) and finally to dielectric properties (σ300K &lt; 10−5 S m−1 for interferential films) as a function of the oxygen concentration in the films.

Constraints on the Decay of ^{180m}Ta.

^{180m}Ta is a rare nuclear isomer whose decay has never been observed. Its remarkably long lifetime surpasses the half-lives of all other known β and electron capture decays due to the large K-spin differences and small energy differences between the isomeric and lower-energy states. Detecting its decay presents a significant experimental challenge but could shed light on neutrino-induced nucleosynthesis mechanisms, the nature of dark matter, and K-spin violation. For this study, we repurposed the Majorana Demonstrator, an experimental search for the neutrinoless double-beta decay of ^{76}Ge using an array of high-purity germanium detectors, to search for the decay of ^{180m}Ta. More than 17kg, the largest amount of tantalum metal ever used for such a search, was installed within the ultralow-background detector array. In this Letter, we present results from the first year of Ta data taking and provide an updated limit for the ^{180m}Ta half-life on the different decay channels. With new limits up to 1.5×10^{19} yr, we improved existing limits by 1-2 orders of magnitude which are the most sensitive searches for a single β and electron capture decay ever achieved. Over all channels, the decay can be excluded for T_{1/2}<0.29×10^{18} yr.