Tb Atoms Research Articles

Synthesis and electrochemical hydrogenation of RxTb2-xNi17 and Tb2Ni17-yMy phases (R = Y, Zr, La; M = Li, Mg)

Alloys from the regions of existence of the solid solutions RxTb2-xNi17 and Tb2Ni17-yMy were synthesized by arc-melting with further annealing at 400 ºС. Quantitative and qualitative composition of alloys and powders of electrode materials was determined by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The Tb/R/Ni and Tb/Ni/Mg ratio in the samples was confirmed also by X-ray fluorescence spectroscopy. The cell parameters of RxTb2-xNi17 (x = 0.5) ternary phases are: a = 8.2987(9) Å, c = 8.0206(8) Å, V = 478.37(9) Å3 for R = Zr, a = 8.3161(6) Å, c = 8.0482(8) Å, V = 482.03(6) Å3 for R = Y and a = 8.3690(6) Å, c = 8.0560(7) Å, V = 488.66(6) Å3 for R = La. Tb atoms were partially substituted by Y, Zr and La atoms because of closeness of atomic radii size. Under experimental condition capacity parameters were 1.81 H/f.u. for the Zr-containing electrode, 2.29 H/f.u. for the Y-containing electrode and 2.31 H/f.u. for the La-containing electrode. In the case of Li,Mg co-doped electrodes we observed more than 2.5 H/f.u. Cell parameters of the Zr- and La-containing phases after hydrogenation increased isotropically. Synthesized hydrides can be interpreted as superstructures with the Tb2Mn17C2.5-type (filled-up of Th2Ni17). The Y0.5Tb1.5Ni17-based electrode demonstrates the potential corrosion at -0.540 V, electrodes with the compositions Zr0.5Tb1.5Ni17 and La0.5Tb1.5Ni17 show -0.413 V and -0.405 V, respectively. Li and Mg-codoped electrodes shoved the corrosion potential -0.410 V (Tb2Ni16.4Li0.2Mg0.4) and -0.550 V for Tb2Ni15.6Li0.6Mg0.8, respectively.

Revealing magnetic and physical properties of TbFe4.4Al7.6: experiment and theory

We report on the magnetic, electrical transport, caloric and electronic structure properties of TbFe4.4Al7.6 polycrystalline alloy using experiment and theory. The alloy crystallizes in tetragonal structure with I4/mmm space group with lattice parameters a = b = 8.7234(5) Å and c = 5.0387(6) Å. It is ferrimagnetic with a compensation temperature of Tcmp∼ 151 K, Curie–Weiss temperature θCW∼ 172.11 K and an effective magnetic moment μeff = (2.37±0.07) μB /f.u with Z = 2. At low temperatures, kinetic arrest-like first-order phase transition is realized through the thermal hysteresis between field-cooled cooling and field-cooled warming curves of M(T) and virgin curves of M(H) and ρ(H) which are outside the hysteresis loops with metamagnetic transition. The high magnetic field suppression of multiple transitions and reduced coercive field Hcoer and remnant magnetization Mrem with increasing temperature are reported. Hcoer and Mrem cease to exist above the compensation temperature Tcmp . A correlation between the isothermal magnetization and resistivity is discussed. Specific heat C(T) analysis reveals a Sommerfeld parameter of γ = 0.098 J⋅mol−1⋅K−2 and a Debye temperature of θD∼351.2 K. The sample is metallic as inferred from the ρ(T) behavior and Sommerfeld parameter. The magnetoresistance of the alloy is low and negative which indicates the suppression of weak spin-fluctuations. This alloy avoids the tricritical point despite first-to-second order phase transition. The electronic and magnetic structure calculations, by making use of full potential linearized augmented plane wave method, suggest metallic ferrimagnetic ground state of TbFe4.4Al7.6 with Tb atoms contributing ferromagnetically (5.87 μB ) and Fe atoms with antiferromagnetic contribution (2.67 μB ), in close agreement with the experimental observation.

Spontaneous Topological (Anti)meron Chains in the Domain Walls of Centrosymmetric Rare‐Earth Magnet

AbstractExploration and manipulation of topological protected magnetic swirls, such as skyrmion, antiskyrmion, meron, and vortex, holds significance for fundamental research and practical applications in high‐density magnetic information storage and spintronics because of their high storage density and low driven current. This study unveils the existence of field‐free spontaneous (anti)meron chains with a topological charge of ±1/2 in the centrosymmetric rare‐earth magnet Tb6Co2.17Si2.5 via in situ real‐space observation. The spin reorientation transition from in‐plane to uniaxial anisotropy contributes to the spontaneous transformation from straight domain walls to topological (anti)meron chains and to stripe domains along the [110] zone axis during in situ cooling. The study further confirms the critical role of the noncollinear magnetic structure of Tb atoms in the formation of topological (anti)meron chains via real‐space observations, first‐principles calculations, and micromagnetic simulations. The spontaneous topological magnetic texture is strongly correlated with the 4f electrons of rare‐earth atoms, enriching and stimulating alternative generation mechanisms of topological spin textures from emerging rare‐earth magnets, and further applications in spintronics.

Aromatic and magnetic properties in a series of heavy rare earth-doped Ge6 cluster anions.

A series of pentagonal bipyramidal anionic germanium clusters doped with heavy rare earth elements, (RE = Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), have been identified at the PBE0/def2-TZVP level using density functional theory (DFT). Our findings reveal that the centrally doped pentagonal ring structure demonstrates enhanced stability and heightened aromaticity due to its uniform bonding characteristics and a larger charge transfer region. Through natural population analysis and spin density diagrams, we observed a monotonic decrease in the magnetic moment from Gd to Yb. This is attributed to the decreasing number of unpaired electrons in the 4f orbitals of the heavy rare earth atoms. Interestingly, the system doped with Er atoms showed lower stability and anti-aromaticity, likely due to the involvement of the 4f orbitals in bonding. Conversely, the systems doped with Gd and Tb atoms stood out for their high magnetism and stability, making them potential building blocks for rare earth-doped semiconductor materials.

Spin–Orbit Torque and Current‐Driven Switching in Pt100‐yTby/Co/AlOx Trilayers

AbstractTo decrease the energy consumption for the electrical manipulation of magnetization, the enhancement of the spin Hall effect through alloying is widely investigated, but the use of rare earth elements is rarely mentioned. This work reports the modification of the spin Hall effect on Pt by doping rare earth Tb atoms. The spin–orbit torque (SOT) performance is significantly enhanced in Pt100‐yTby alloyed heavy metal (HM) layer. Compared with the Tb‐free sample, the damping‐like effective field per unit current density increases to 1.9 times in the samples with Tb content between 5% and 10%. The critical current density for magnetization reversal is greatly reduced by 65% in a device with Pt87Tb13 HM layer and the in‐plane assistant field as small as ±20 Oe is sufficient for the deterministic switching in the same device. By magneto‐optical Kerr effect imaging, it is confirmed that the increased in‐plane field can effectively compensate the Dzyaloshinskii–Moriya interaction (DMI), which not only helps to reduce the critical current, but also facilitates the domain wall motion and is beneficial for the switching process. All results show that the Pt‐Tb alloy is a competitive candidate for low‐power spintronic devices.

Magnetocaloric effect over a temperature span in (Gd x Tb1-x )3Al2 compounds

As an environmentally friendly, more efficient and operation-reliable technology, magnetic refrigeration is promised to replace traditional gas compression refrigeration. In our study, we studied the influence on magnetism and magnetocaloric effect of (Gd x Tb1-x )3Al2 (x=0, 0.2, 0.4, 0.6, 0.8, 1) systematically. These results indicated that the increase of Gd concentration increased the lattice constants due to larger atomic radius of Gd atom. Simultaneously, the Curie temperature is dependent on magnetic interaction between Gd atom and Tb atom, and reduced from 279 K to 190 K for x=1 to x=0. Arrott plots indicated that (Gd x Tb1-x )3Al2 compounds showed the characteristics of second-order magnetic phase transition. Under a magnetic field of 0-2 T, the maximum isothermal magnetic entropy (-ΔSM)max of (Gd x Tb1-x )3Al2 (x=0, 0.2, 0.4, 0.6, 0.8, 1) compounds are 4.13, 3.79, 3.91, 4.08, 3.96 and 3.98 J/(kg K), respectively. Moreover, refrigeration capacity RC of (Gd x Tb1-x )3Al2 are 59.7, 69.0, 77.6, 65.0, 76.1 and 75.6 J/kg, respective. Adjustable Curie temperature, lower magnetic and thermal hysteresis, (-ΔSM) and RC suggested that, (Gd x Tb1-x )3Al2 compounds can be used as candidates for magnetic refrigeration.

Exchange coupling effect and magnetic properties in sintered RE-Fe-B magnets

Preparing the magnetic materials bearing both a high coercive field and a high energy product is a great challenge. In this paper the content of Nd was reduced in Nd-Fe-B for enhancing the interaction effect as well as for increasing the energy product, and Tb-Fe-B powders were mixed to enhance the coercivity. In the sintered RE-Fe-B magnets some of Tb atoms diffuse into the outer regions of Nd-Fe-B grains, and Tb-rich RE2Fe14B grains also exist with the crystal size at micrometer scale. The recoil loops bear the spring behaviors, and the reversal susceptibility implies the availability of exchange coupling effect among the micro grains. The activation volume also indicates that the exchange coupling is effective in magnetization reversal. So the magnetization reversal in Nd-Fe-B grains could be restrained by the high anisotropy phase of Tb-rich core. Therefore, besides the effects of Tb-diffusion into grain outer region and the intergranular phase, the exchange coupling effect could not be neglected in improving the coercivity in the Nd-content-reduced magnets, and both a high coercive field of 20.0 kOe and a high energy product of 50.1 MGOe are achieved in the micro-crystal composite magnets.

The Structure of Terbium in the Ferromagnetic State.

Metals typically crystallize in highly symmetric structures due to their nondirectional and nonsaturated metallic bonds. Here, we report that terbium metal in its ferromagnetic state adopts an unusual low-symmetry orthorhombic structure with a Cmcm space group. A similar structure has been previously observed only in a few actinide metals with bonding 5f electrons at ambient pressure, such as uranium, neptunium, and plutonium, but with different nearest coordination numbers and bond-length variations. The Tb atom occupies the 4c site (0, ∼0.1661, 1/4), building up -[Tb-Tb]- layers stacking along the b-axis. Our first-principles many-body calculations of the crystal field splitting in the correlated Tb 4f-shell demonstrate that the Cmcm structure for ferromagnetic terbium is stabilized by magneto-elastic forces due to a secondary order of quadrupolar moments in the ferromagnetic state. These findings are significant for further understanding of the nature of terbium, including its electron structure, energy bands, phonons, and magnetism.

Growth and characteristics of terbium doped Ga2O3 luminescent films

Terbium (Tb) doped Ga2O3 films were deposited on sapphire substrates by pulsed laser deposition (PLD) at substrate temperatures ranging from 100 to 500 ℃. Energy dispersive spectroscopy results show that Tb atoms are more readily incorporated into Ga2O3 at high temperatures. X-ray diffraction analysis indicates that (−201) oriented monoclinic Tb doped Ga2O3 films can be obtained at a substate temperature of 500 ℃. All films have high transmittance of over 80 % in the visible and infrared region. The peaks observed at 486, 540, 582, and 622 nm in the room temperature (RT) photoluminescence spectra for all samples are ascribed to the 5D4–7F6, 5D4–7F5, 5D4–7F4, and 5D4–7F3 transitions, respectively. No peak shift for all transitions in the PL spectra is found with temperature decreasing from RT to 60 K. The results suggest that Tb doped Ga2O3 films are promising for realizing the full color microscale light emitting diodes.

Magnetic properties of the quasicrystal approximant Au65Ga21Tb14

The magnetic properties of the quasicrystal approximant ${\mathrm{Au}}_{65}{\mathrm{Ga}}_{21}{\mathrm{Tb}}_{14}$ were investigated using magnetization and neutron diffraction experiments. The temperature dependences of the magnetic susceptibility and magnetization curve indicate dominant ferromagnetic interactions, whereas a whirling antiferromagnetic order was observed in neutron diffraction experiments. In the antiferromagnetic phase, the magnetic moments are aligned almost perpendicular to a pseudofivefold symmetry axis, which corresponds to the easy-axis direction of a Tb atom. Magnetic properties similar to those of ${\mathrm{Au}}_{72}{\mathrm{Al}}_{14}{\mathrm{Tb}}_{14}$ in spite of the substantial difference in the Au concentration suggest the robustness of the easy-axis anisotropy against the chemical environment.

Enhancement of terbium efficiency by gallium and copper co-doping in (Pr, Nd)-Fe-B sintered magnets

It is well known that Tb substitution for (Pr, Nd) in (Pr, Nd)-Fe-B based sintered magnetic materials is an effective way to increase intrinsic coercivity, but it is not quite clear whether the increment depends on the different matrix phases with various doping ingredient or not, which is essential to develop high quality magnets with high coercivity more efficiently and effectively with economic consumption of expensive Tb and other costly heavy rare earths. In this paper, we investigated the efficiency of Tb substitution for magnetic property in (Pr, Nd)-Fe-B sintered permanent magnets by co-doping Ga and Cu elements. It is shown that Ga and Cu co-doping can effectively improve the efficiency of Tb substitution to increase the thermal stability and the coercivity. The intrinsic coercivity increases up to 549 and 987 kA/m respectively by 1.5 wt% and 3.0 wt% Tb substitution in Ga and Cu co-doped magnets while the intrinsic coercivity increases up to only 334 and 613 kA/m respectively by the same amounts of Tb substitution in non-Ga and low-Cu magnets. In other words, it demonstrates that there is about 329–366 kA/m linear equivalent enhancement of intrinsic coercivity by 1.0 wt% Tb substitution for (Pr, Nd) in Ga and Cu co-doped magnets. The temperature coefficients of both intrinsic coercivity β and remanence α at 20–150 °C by 3.0 wt% Tb substitution for the magnets with Ga and Cu co-doping are −0.47%/K and −0.109%/K respectively, and in contrast those values are −0.52%/K and −0.116%/K respectively for the non-Ga and low-Cu magnets. It is the principal reason for more efficient enhancement of magnetic property by Tb substitution in the Ga and Cu co-doped magnets in which Tb atoms are expelled from triple junction phases (TJPs) to penetrate into the grain boundary phases (GB phases) and thus modify the grain boundary. It is prospected that the efficiency of Tb substitution would rely on different matrix phases with various doping constituents.

Hydrolytically stabilized 5-hydroxyisophthalate appended Tb-MOF as a twofold chemosensor for discerning detection of 2,4,6-trinitrophenol and ferric ion: Structural, topological and mechanistic sensing exploration via experimental and computational studies

Newly constructed hydrolytically stabilized three-dimensional (3D) Tb-ISH MOF [{Tb2(L)3(µ2-HCOO)(DMF)2(H2O)2}.6H2O·2DMF]n (H2L = 5-hydroxyisophthalic acid) was solvothermally synthesized by incorporating 5-hydroxyisophthalate (L) as a linker. The 3D Tb-ISH MOF was structurally explicated using distinctive (physicochemical, spectral, PXRD, single crystal X-ray, topological, BET, thermal and DFT) studies. The synthesized MOF crystallized in the monoclinic system with C2/m space group and formed a 3D architecture with distorted tricapped trigonal-prismatic geometry. The topological analysis demonstrated that Tb-ISH MOF consists of layers in the plane (001) built with Tb atoms connected by formate and 5‐hydroxyisophalte linkers. The layers in Tb-ISH MOF are bundled together with hydrogen bonds between 5‐hydroxyisophthalate ligand and featured with (6,3)Ia type topology. The fluorescence titration experimental study revealed that Tb-ISH MOF displayed great selectivity and sensitive quenching behaviour towards 2,4,6-trinitrophenol (TNP) and Fe3+ ion with KSV values of 4.00 × 105 and 6.42 × 105 and a detection limit of 1.73 and 1.37 µM, respectively. Further, DFT (B3LYP/6-31G(d) and BET studies were performed in order to comprehend the sensing pathways. Moreover, the recycling experiment also proposed that a chemosensor exhibits fine reversibility without any destruction of framework structure. The present study outlined the great sensitivity, selectivity, and fine recyclability of Tb-ISH MOF in an aqueous system. Thus, the upshot of the overall results may engender more exploration to design and synthesize efficiently responsive chemosensor by encompassing structurally functionalized ligands which could be practically efficacious for the protection of the environment, human health, and homeland security.

Tb2O@C2(13333)-C74: A Non-Isolated Pentagon Endohedral Fullerene Containing a Nearly Linear Tb-O-Tb Unit.

Terbium has been added to the list of elements that form oxide clusters inside fullerene cages. Tb2O@C2(13333)-C74 has been isolated as a byproduct of the electric arc synthesis of the azafullerene Tb2@C79N. Cocrystallization of Tb2O@C2(13333)-C74 with Ni(OEP) (where OEP is the dianion of octaethylporphyrin) in toluene yielded black needles of Tb2O@C2(13333)-C74·NiII(OEP)·1.5C7H8 that have been examined by single-crystal X-ray diffraction. The resulting structure shows that a nearly linear Tb-O-Tb unit is contained in a C2(13333)-C74, which has two sites where pentagons share an edge to form pentalene units at opposite ends of the fullerene. Unlike the usual situations where metal atoms in fullerenes that do not obey the isolated pentagon rule are situated within the folds of the pentalene units, the Tb atoms in Tb2O@C2(13333)-C74 are positioned to the side of the pentalene units and near-neighboring hexagons. The magnetic properties of Tb2O@C2(13333)-C74 have been examined starting from the experimental geometry, using ab-initio multiconfigurational methods. The computations predict that Tb2O@C2(13333)-C74 will show strong axiality, which would make it a single-molecule magnet with a large magnetic anisotropy barrier.

Plateau-like magnetoresistance and topological Hall effect in Kagome magnets TbCo2 and DyCo2

Magnetoresistance (MR) and Hall resistivity of TbCo2 and DyCo2 with a Co Kagome lattice were investigated. Apart from giant negative magnetoresistance (MR) at TC, plateau-like MR and a topological Hall effect (THE) are observed at a low magnetic field for each compound below respective TC. The plateau-like MR is attributed to a compensation of negative MR with a ferromagnetically ordered structure of Tb atoms by positive MR with a noncoplanar spin structure of the Co Kagome lattice. The THE is attributed to the noncoplanar spin structure of the Co Kagome lattice only. The MR and the Hall resistivity of each compound are reduced dramatically and undergo a reversal of its sign during cooling. The reversal phenomenon at the low temperature can be related to the freezing of spins of Co atoms. The transport in DyCo2 is more sensitive to magnetic fields than that in TbCo2 which is consistent with a stronger 4f–3d interaction. Observations of these transport phenomena make RCo2 compounds promising for functional applications in spintronic devices.

Effect of intergranular phase proportion in sintered Nd-Fe-B magnets on subsequent grain boundary diffusion using Tb-Cu alloy

Magnetic properties and microstructures of sintered Nd-Fe-B magnets with different Nd-Cu powders addition (0, 2.7, 4.5, 6.2 and 8 wt%) and their corresponding diffused magnets using Tb-Cu alloys were studied systematically. The results showed that the enhancement of coercivity after diffusion was positively correlated with the intergranular phase proportion of the base substrates, and the relatively larger coercivity increments with 8.69 and 9.16 kOe were obtained at the addition of 6.2 and 8 wt% respectively, while the coercivity increments only reached 3.54 kOe and 4.00 kOe for the diffused magnets prepared by the substrates with 0 and 2.7 wt% Nd-Cu powders addition. The further microstructure analyses demonstrated that the higher coercivities were mainly attributed to the rather deeper diffusion depths of Tb elements, and the Nd-rich grain boundary phases in the base substrates were beneficial to construct the effective diffusion channels for subsequent diffusion process. Meanwhile, just due to the lack of efficient diffusion channels in the substrates with lower intergranular phase proportion, a large amount of Tb atoms accumulated on the interface between diffusion source and base magnet, forming a Tb-Fe transition layer and significantly deteriorating the utilization of heavy rare earths. This work supplemented insight and experimental foundation for the base substrate design in the preparation of diffused magnet with high performance.

Expanding the Knowledge of the Selective-Sensing Mechanism of Nitro Compounds by Luminescent Terbium Metal-Organic Frameworks through Multiconfigurational ab Initio Calculations.

The current research shows that the excited-state dynamics of the antenna ligand, both in the interacting system sensor/analyte and in the sensor without analyte, is a safe tool for elucidating the detection principle of the luminescent lanthanide-based metal-organic framework sensors. In this report the detection principle of the luminescence quenching mechanism in two Tb-based MOFs sensors is elucidated. The first system is a luminescent Tb-MOF [Tb(BTTA)1.5(H2O)4.5]n (H2BTTA = 2,5-bis(1H-1,2,4-triazol-1-yl) terephthalic acid) selective to nitrobenzene (NB), labeled as Tb-1. The second system is {[Tb(DPYT)(BPDC)1/2(NO3)]·H2O}n (DPYT = 2,5-di(pyridin-4-yl) terephthalic acid, BPDC = biphenyl-4,4'-dicarboxylic acid), reported as a selective chemical sensor to nitromethane (NM) in situ, labeled as Tb-2. The luminescence quenching of the MOFs is promoted by intermolecular interactions with the analytes that induce destabilization of the T1 electronic state of the linker "antenna", altering thus the sensitization pathways of the Tb atoms. This study demonstrates the value of host-guest interaction simulations and the rate constants of the radiative and nonradiative processes in understanding and elucidating the sensing mechanism in Ln-MOF sensors.

Diffusion behavior and coercivity enhancement of Tb-containing NdFeB magnet by dip-coating TbH3

There is a growing demand for high coercivity of NdFeB magnets with low heavy rare earth in the emerging applications. In this work, dip-coating 0.02 g and 0.09 g TbH3 on the Tb-containing NdFeB magnet enhance coercivity at room temperature，respectively. The highest coercivity achieve about 30 kOe at room temperature after diffusion, which can apply to traction motors of electric vehicles. The magnetic field intensity distribution of magnet was analyzed by finite element method. Microstructures show TbH3 coat contents and original composition of NdFeB magnet influences the formation of Tb-rich shell and grain boundary phase, and determine finally diffusion depth and Tb concentration. The Tb atoms diffuse into the interior of the magnet, forming a network Tb-rich shell existed around Nd2Fe14B grains, resulting in the coercivity enhancement.

Tailoring the diffusion depth and microstructure of RE-Fe-B magnets by low-pressure grain boundary diffusion process

A novel grain boundary diffusion process (GBDP) with low-pressure technology was employed to develop RE-Fe-B sintered magnets with a thickness of 2 mm. The gas pressure promotes Tb atoms to permeate the deeper of the magnets due to the uniform and continuous RE-rich phase, increasing the diffusion depth from 345 µm to 880 µm. According to the results acquired by computation, diffusion coefficients (D) of vacuum grain boundary diffusion process (VGBDP) and low-pressure grain boundary diffusion process (LPGBDP) rose from 2.27 × 10−13 m2/s to 2.95 × 10−12 m2/s, respectively. The increasing magnetocrystalline anisotropic field (122.2 kOe) and the optimized microstructure jointly determine the improvement of coercivity, which increases significantly from 17.47 kOe to 27.73 kOe by low-pressure diffusion treatment, 58.7% higher than the original magnet. Meanwhile, the homogeneous grain boundary phase and the thicker Tb-shell were mainly responsible for the excellent temperature stability in 20°C-200°C. This work proposes a viable method for preparing the RE-Fe-B magnets with slight HREE and high comprehensive performance.

Magnetic molecules as local sensors of topological hysteresis of superconductors

Superconductors and magnetic materials, including molecules, are key ingredients for quantum computing and spintronics. However, only a little is known about how these materials interact in multilayer nanostructures like the hybrid architectures nowadays under development for such advanced applications. Here, we show that a single layer of magnetic molecules, Terbium(III) bis-phthalocyaninato (TbPc2) complexes, deposited under controlled UHV conditions on a superconducting Pb(111) surface is sensitive to the topology of the intermediate state of the superconductor, namely to the presence and evolution of superconducting and normal domains due to screening and penetration of an external magnetic field. The topological hysteresis of the superconducting substrate imprints a local evolution of the magnetisation of the TbPc2 molecules in the monolayer. Element and surface selective detection is achieved by recording the X-ray magnetic circular dichroism of the Tb atoms. This study reveals the impressive potential of magnetic molecules for sensing local magnetic field variations in molecular/superconductor hybrid devices, including spin resonators or spin injecting and spin filtering components for spintronics applications.

Low-Temperature Magnetothermodynamics Performance of Tb1-xErxNi2 Laves-Phases Compounds for Designing Composite Refrigerants

In this paper, the results of heat capacity measurements performed on the polycrystalline Tb1-xErxNi2 intermetallic compounds with x = 0.25, 0.5 and 0.75 are presented. The Debye temperatures and lattice contributions as well as the magnetic part of the heat capacity were determined and analyzed. The heat capacity measurements reveal that the substitution of Tb atoms for Er atoms leads to a linear reduction of the Curie temperatures in the investigated compounds. The ordering temperatures decrease from 28.3 K for Tb0.25Er0.75Ni2 to 12.9 K for Tb0.75Er0.25Ni2. Heat capacity measurements enabled us to calculate with good approximation the isothermal magnetic entropy ΔSmag and adiabatic temperature changes ΔTad for Tb1-xErxNi2, for the magnetic field value equal to 1 T and 2 T. The optimal molar ratios of individual Tb0.75Er0.25Ni2, Tb0.5Er0.5Ni2 and Tb0.25Er0.75Ni2 components in the final composite were theoretically determined. According to the obtained results, the investigated composites make promising candidates that can find their application as an active body in a magnetic refrigerator performing an Ericsson cycle at low temperatures. Moreover, for the Tb0.5Er0.5Ni2 compound, direct measurements of adiabatic temperature change in the vicinity of the Curie temperature in the magnetic field up to 14 T were performed. The obtained high-field results are compared to the data for the parent TbNi2 and ErNi2 compounds, and their magnetocaloric properties near the Curie temperature are analyzed in the framework of the Landau theory for the second-order phase transitions.