Grain Boundary Activation Energy Research Articles

Effects of Fe2+ on dielectric and magnetic properties in rare earth garnet type high entropy oxides

Given the important role played by the valence state of the transition metal in determining material this paper investigates the effect of Fe2+ content on the structure and dielectric properties of garnet-structured high entropy oxides (Y0.2Eu0.2Er0.2Dy0.2Lu0.2)3(Al0·5Fe0.5)5O12 through Fe2+ doping. The results of XPS and Mӧssbauer spectra showed that the Fe2+ content in the tetrahedron increased with Fe2+ doping. With increasing Fe2+ content, the dielectric constants gradually increased, and the maximum dielectric constant reached 2.78 × 104 at 100 Hz under 30 °C. The analysis of the AC impedance spectrum and electrical conductivity revealed that the difference between the activation energy of grain boundary and grain conductivity resulted in increased dielectric constants of the samples. In addition, the doping of Fe2+ increased the maximum magnetization of the samples. This work provides a new idea for designing giant dielectric materials and magnetic materials with a high entropy strategy.

Modeling the effect of prior austenite grain size on bainite formation kinetics

While experiments show that refining the prior austenite grain size can either accelerate or decelerate bainite formation in steels, kinetic models based on the successive nucleation of bainitic ferrite subunits can only predict an acceleration. In this work we develop a physically-based model for bainite kinetics assuming a displacive growth mechanism which is able to reproduce both faster and slower bainite formation kinetics induced by austenite grain refinement. A theoretical analysis of the model and comparison against published experimental data show that slower kinetics for smaller grains is favored as the difference between the activation energy for grain boundary and autocatalytic nucleation of bainite increases, and as the austenite grain refinement results in finer bainite sub-units. We also theoretically analyze the density of initially present potential nucleation sites for bainite and show that the values of density used in other published bainite nucleation models are mostly underestimated. After using physically consistent values for the density of potential nucleation sites, we were able to calculate the apparent lengthening rate of bainite sheaves which were in line with experimentally measured lengthening rates.

Widening the temperature range and improving the linearity of CaCu3Ti4O12 ceramics for high-temperature NTC thermistor application through entropy engineering strategy

The entropy engineering strategy has been used for the first time to improve the grain boundary (GB) barrier of CaCu3Ti4O12 (CCTO) ceramics, in order to solve its nonlinear problem at around 300 ℃ and expand its application in the field of high-temperature thermistors. To achieve this goal, we prepared (CaBaEuZnSr)0.2Cu3Ti4O12 (CBEZSCT) high-entropy ceramics, and the GB spontaneous segregation properties were exploited to improve the GB resistance of CBEZSCT ceramics. The results show that the GB activation energy of CBEZSCT high-entropy ceramics (0.87 eV) is higher than that of CCTO ceramics (0.7 eV), which linearizes the resistance temperature curve and extends the application temperature limit from 300° to 750 °C. The proposed method of using a high entropy strategy to tune the GB resistance of CCTO to optimize its performance is highly effective, thus providing a new way of thinking about studying high-performance CCTO materials.

Distinct dominant dielectric relaxation mechanisms in CaCu3Ti4O12 – LaMO3 (M = Mn and Fe) perovskite oxide solid solution

Two synthesized perovskite oxide solid solutions, CaCu3Ti4O12 – LaMnO3 and CaCu3Ti4O12 – LaFeO3, possess a crystalline structure embracing an amalgamation of two distinct phases, namely, hexagonal and orthorhombic phases in CaCu3Ti4O12 – LaMnO3 and cubic and orthorhombic phases in CaCu3Ti4O12 – LaFeO3. Examination of dielectric properties reveals colossal dielectric constant (εr), the peak magnitude of εr at 1 kHz being approximately 6×103 and 2.5×104 for Mn and Fe based compound, respectively. Further, complex impedance investigation (CII) establishes the activation energy (Ea) of grains (0.21 eV and 0.07 eV for Mn and Fe based solid solution, respectively) and grain boundaries (0.19 eV and 0.19 eV for Mn and Fe based solid solution, respectively). The deviation in Ea of grains and grain boundaries, as established through CII, in both, Mn and Fe based samples validates the existence of Maxwell-Wagner (M − W) relaxation. The AC conductivity spectrum for both the samples obeying the Jonscher's universal power law (JUPL): σ(ω,T)=σdc+Aωn. The Ea of bulk samples (0.37 eV and 0.19 eV for Mn and Fe based solid solution, respectively) authenticates predominant M − W relaxation (interfacial polarization) with polaron hopping playing the secondary role in Mn based sample, while both, polaron hopping and M − W relaxation being identical contributors towards dielectric nature of Fe based sample.

Reassessment of the effect of space charge potential on the electrical conductivity of polycrystalline ceramics

AbstractThe calculation of space charge potential, the difference of the activation energy of grain boundary and grain, and the ratio of conductivity of grain boundary and grain at different temperatures of the polycrystalline ceramics have been reappraised in the present model, in which charge carriers hopping through bulk and grain boundary barriers with different mobility are taken into account. It is evidenced that the present model is valid and more precise than previous models, and thus, it is concluded that the assumption that the mobility of charge carriers hopping through bulk and grain boundary barrier is the same made by the previous studies is unsuitable.

Sintering characteristics and electrical properties of 5YSZ electrolyte

5YSZ (5 mol. %Y2O3 stabilized ZrO2) solid electrolytes play a key role in NOx sensors for their important ion conduction performance in the sensing process. In this study, the influence of sintering and test temperature on 5YSZ solid electrolytes was investigated. The 5YSZ solid electrolyte was prepared by the tape casting process, followed by the sintering process. The ionic conductivity of the 5YSZ solid electrolyte sintered at 1450 °C is higher than that of other samples. The conductivity and activation energy of grain interior and grain boundary showed opposite tendency. The performance of ion conductivity was attributed to (1) the higher test temperature being applied to the working electrolyte and accelerated transfer efficiency and (2) enhanced diffusion of oxygen ions, which increased through the formation of dense structure.

Enhanced linearity of CaCu3Ti4O12 by changing energy band structure induced by Fe3+ doping for high temperature thermistor application

Polycrystalline oxide materials exhibit semiconductor properties due to grain boundary (GB) and grain characteristics, which enrich the variety of applications. However, how to regulate the energy band structure of grains and the potential barriers at GBs through defect engineering is crucial to achieve a high performance electronic device. Herein, it is found that Fe3+ ions can change the grain energy band structure of CaCu3Ti4O12 (CCTO) materials, which enhances the linearization of the resistance–temperature curve (lnρ–1000/T) in the high temperature region. First principles calculation indicates that Fe3+ doping narrows the forbidden band and induces new impurity energy levels in the forbidden band, which matches the conclusion that the resistivity–temperature dependence of grains shifts toward the low-temperature region as derived from impedance spectroscopy. This shift results in no monotonic variation in grain resistivity within the application temperature region, thus enhancing the linearity of the lnρ–1000/T curve of CCTO materials in the high temperature region. In addition, Fe3+ ions can modulate the activation energy of CCTO materials in a wide range by changing the activation energy of GBs, which broadens the temperature range of CCTO. The significance of this work lies not only in achieving linearization of CCTO materials for high temperature thermistor application, but more importantly, the method presented here provides an avenue for the study of polycrystalline semiconductor materials.

Significantly enhanced varistor properties of CaCu3Ti4O12 based ceramics by designing superior grain boundary: Deepening and broadening interface states

Significantly enhanced varistor properties via tailoring interface states were obtained in Ca 1–2 x /3 Y x Cu 3 Ti 4 O 12 -SrCu 3 Ti 4 O 12 composite ceramics. The breakdown field was improved to 35.8 kV cm −1 and the nonlinear coefficient in 0.1–1 mA cm −2 was enhanced to 14.6 for Ca 0.67 Y 0.5 Cu 3 Ti 4 O 12 -SrCu 3 Ti 4 O 12 . Noticeably, the withstand voltage of single grain boundary reached up to 24 V while the reported ones were constant to about 3 V. Greatly improved properties were attributed to the formation of superior grain boundary rather than the reduced grain size. Surprisingly, with distinct discrepancy of nonlinear performance in the composites, the resistance and activation energy of grain boundary exhibited little differences. Based on the double Schottky barrier at grain boundary and the field-assisted thermal emission model, it was found that the excellent electrical nonlinearity arose from the formation of deeper and broader interface states at grain boundary. In this case, interface states were not easily entirely filled and the barrier could maintain its height under applied voltage. This work provides a novel routine for enhancing the varistor properties of CaCu 3 Ti 4 O 12 based ceramics by manipulating interface states at grain boundary.

Ca9Al(PO4)7 based sintered glass-ceramic for high dielectric breakdown strength

A novel Ca9Al(PO4)7 (CAP) based sintered glass-ceramic has been synthesized via the glass melting process and temperature controlled crystallization. The mechanisms of high dielectric breakdown strength (DBS) of the glass-ceramic were analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy, crystal structure and high temperature complex impedance spectroscopy. CAP has a crystal structure similar to β-Ca3(PO4)2 (β-TCP) and a higher band gap (Egap), which makes it difficult for valence electrons to break away from binding and become free charges. At the same time, the isolated vacancy formed by Al replacing Ca becomes a capture site to prevent the transmission of free charge. Furthermore, CAP based glass-ceramic have a high activation energy of grain and grain boundary, which impedes the movement of free charges. All these endow this CAP based sintered glass-ceramic with a high DBS of 110.5 ± 5.3 kV/mm.

Grain size modulated (Na0.5Bi0.5)0.65Sr0.35TiO3-based ceramics with enhanced energy storage properties

• 0.9NBST-0.1BMS lead-free ceramics with W rec = 6.68 J/cm 3 and η = 89.1 % were designed and fabricated. • Small grain size and high activation energy of grain boundary leads to high breakdown field (405 kV/cm). • The energy storage potential ( W rec /E b ) is up to 0.01649 μC/cm 2 . • Excellent fatigue endurance over 10 5 electrical cycles (the W rec variation is less than 1.5%). Ferroelectric ceramics, as a potential candidate for high-power energy storage capacitors, lies in their excellent recoverable energy storage density ( W rec ) and outstanding efficiency ( η ) in practical applications. Herein, a new type of lead-free ceramics (1- x )(Na 0.5 Bi 0.5 ) 0.65 Sr 0.35 TiO 3 - x BiMg 0.5 Sn 0.5 O 3 or (1- x )NBST- x BMS was prepared with the aim of enhancing the breakdown strength ( E b ) and reducing the energy storage loss through grain refinement. It was found that E b of 0.9NBST-0.1BMS reaches 405 kV/cm due to the reduction in the grain size of ceramic and thus the extremely high ratio of grain boundary resistance to grain resistance. Besides, a remarkable energy-storage performance was obtained, that is, W rec and η are ∼ 6.68 J/cm 3 and 89.1% at 405 kV/cm, respectively, along with excellent stability in terms of frequency, temperature, and fatigue endurance. The outstanding energy-storage performance is resulted from modulating the grain size via doping the moderate content of Bi 3+ and Mg 2+ /Sn 4+ , which is beneficial to increase the breakdown field by increasing resistivity under high electric field while increasing the grain boundary activation energy and promote the formation of a relaxor state at the same time. More importantly, energy storage potential (defined as W rec /E b ) is up to 0.01649 μC/cm 2 , being the highest value reported so far for BNT-based ceramics in energy-storage application. Our results pave the way for practical applications of NBST-based ferroelectric capacitors with excellent energy storage performance.

Structural evolution and dielectric properties of (Bi, Mg, Zr)-doped BaTiO3 ceramics for X8R-MLCC application

The (1-x) BaTiO3-x (0.5Bi2O3-0.67MgO-0.33ZrO2) ceramics (x = 5, 10, 15 and 20 mol%) are fabricated by a conventional solid-state method in a reducing atmosphere. All ceramics display a pure perovskite phase without any trace of secondary phase, and a phase transition from tetragonal phase to pseudo-cubic phase occurs between x = 0.1 and x = 0.15. The dielectric analysis manifests that both the dielectric constant and insulation resistivity at room temperature decrease with increasing dopants, which is mainly related to the reduction of grain boundaries. Meanwhile, high dielectric constant (∼2020) and excellent insulation resistivity (∼4.81 × 1013 ΩΩ ·cm) are obtained when x = 0.05. Besides, the temperature stability of ceramics in the high temperature region is improved with little BMZ-doping, and BMZ05 ceramic satisfies the EIA X8R standard. The complex impedance demonstrates that obvious heterogeneous interfaces and strong interface polarization are existed in ceramics. The fitted activation energy of grain boundary reflects that the long-range hopping polarization of oxygen vacancies dominates in the dielectric constant of ceramics when x < 0.1, while the short-range hopping polarization of defect dipoles dominates when x > 0.15.

Structural and dielectric properties, and nonlinear electrical response of the CaCu3-xZnxTi4O12 ceramics: Experimental and computational studies

CaCu3-xZnxTi4O12 ceramics (x = 0, 0.05, 0.10) were successfully prepared by a conventional solid-state reaction method. Their structural and dielectric properties, and nonlinear electrical response were systematically inspected. The X-ray diffraction results indicated that single-phase CaCu3Ti4O12 (JCPDS no. 75–2188) was obtained in all sintered ceramics. Changes in the lattice parameter are well-matched with the computational result, indicating an occupation of Zn2+ doping ions at Cu2+ sites. The overall tendency shows that the average grain size decreases when x increases. Due to a decrease in overall grain size, the dielectric permittivity of CaCu3-xZnxTi4O12 decreases expressively. Despite a decrease in the dielectric permittivity, it remains at a high level in the doped ceramics (~3,406–11,441). Besides retention in high dielectric permittivity, the dielectric loss tangent of x = 0.05 and 0.10 (~0.074–0.076) is lower than that of x = 0 (~0.227). A reduction in the dielectric loss tangent in the CaCu3-xZnxTi4O12 ceramics is closely associated with the enhanced grain boundary response. Increases in grain boundary resistance, breakdown electric field, and conduction activation energy of grain boundary as a result of Zn2+ substitution are shown to play a crucial role in improved grain boundary response. Furthermore, the XPS analysis shows the existence of Cu+/Cu2+ and Ti3+/Ti4+, indicating charge compensation due to the loss of oxygen lattice. Based on all results of this work, enhanced dielectric properties of the Zn-doped CCTO can be explained using the internal barrier layer capacitor model.

Design and characterization of novel manganite perovskites Ba1-xBixTi1-xMnxO3 (0≤x≤0.2)

Polycrystalline manganite powders of Ba1-xBixTi1-xMnxO3 (x = 0, x = 0.1 and x = 0.2) were synthesized by the conventional solid-state reaction process. Their crystal structure, morphological, optical, dielectric and electrical properties were investigated. X-ray diffraction of the prepared samples was made at room temperature and confirmed the formation of a perovskite phase. Structural refinement, using the Rietveld method, revealed a tetragonal P4mm phase of pure BTO and a tetragonal P4/mmm phase with the presence of vacancies for both doped samples (x = 0.1 and x = 0.2). Scanning electron microscopy indicated that the perovskite samples had a grain size smaller than 1 μm. From UV–vis–NIR spectra, we found that the band gap reduces from 3.29 eV to 1.48 eV with the increase of Bi and Mn amounts, resulting in a shift of the absorption wavelength region toward the visible range. Dielectric analysis was conducted in a wide range of temperatures at different frequencies. Phase transitions were identified from thermal dielectric results, showing that the samples exhibited a non-relaxor behavior. The structural transformation from tetragonal to cubic structure corresponding to the transition from ferroelectric phase to paraelectric phase was observed in the dielectric properties investigation. The complex impedance spectroscopy indicated the presence of grain and grain boundary effects in the conduction mechanism. Electrical analysis showed that doping with Bi and Mn enhanced the DC conductivity. Furthermore, the DC conductivity temperature dependence confirmed that the studied samples present a semiconductor behavior. The activation energies of grain and grain boundaries depended on the amount of incorporated Bi and Mn. The activation energy of grain varied between 0.54 and 0.87 eV suggesting that the DC electrical conductivity is governed by ionized oxygen vacancies. The activation energy of grain boundaries varied between 0.85 and 0.58 eV.

Grain size engineering in nanocrystalline Y2Zr2O7: A detailed study on the grain size correlated electrical properties

Abstract A set of nanocrystalline Y2Zr2O7 (YZO) ceramic materials possessing grain sizes ranging from 7 nm to 65 nm was prepared by chemical co-precipitation technique followed by conventional sintering at various temperatures. Evolution of structure and grain growth was investigated by XRD and TEM analysis. Disordered pyrochlore phase of YZO was obtained. Electrical conductivity of YZO has been increased with increasing measuring temperature as well as grain size. The behavior of total electrical conductivity comprising grain interior and grain boundary components was studied. When the grain size was increased, the activation energy for grain boundary and total ionic conduction has been decreased from 1.59 to 1.51 eV whereas the same for bulk grain conductivity remained more or less the same near to 1.43 ± 0.01 eV. The Jonscher’s universal law had explained the behavior of ac conductivity suggesting a long-range hopping of mobile ions-based conduction in YZO. In addition, Maxwell–Wagner model had explained the dielectric behavior of YZO and showed an increasing dielectric constant with increasing grain size. Electric modulus, analysed by Kohlrausch-Williams-Watts function, showed an increasing relaxation frequency at higher grain sizes. A complete electrical characterization of YZO ceramics with good correlation with their grain size is reported.

Grain size effect on the electrical properties of nanocrystalline Gd2Zr2O7 ceramics

A detailed study on the effect of grain size of nanocrystalline Gd2Zr2O7 (GZO) ceramics on its electrical properties, particularly the ionic conductivity, is reported. The nanocrystalline GZO was prepared by chemical co-precipitation method. The GZO ceramic with different grain sizes from 5 to 55 nm was fabricated by sintering them at different temperatures varying from 800 to 1400 °C. Structural studies were performed by X-ray diffraction and Raman spectroscopy and found the cubic pyrochlore phase of GZO in all cases. Their crystallite size has been increased from 5 to 55 nm as well as the structural ordering has been increased with the increase in sintering temperature. The ac electrical impedance analysis showed a dramatic increase in ionic conductivity with increasing grain size. The ionic conductivity measured at 700 °C was 8.7 × 10−6, 12.5 × 10−6, 20.4 × 10−6 and 45.4 × 10−6 S cm−1 for respective grain sizes 5, 12, 25, and 55 nm of GZO ceramics. Increase in conductivity was correlated to the increase in grain size. The activation energy for grain conductivity was found to be 1.42 ± 0.01 eV for all GZO ceramics irrespective of their grain size. However, the activation energy of grain boundary and total conductivity had decreased with increasing grain size. The activation energy for total conductivity was obtained to be 1.5, 1.48, 1.46 and 1.42 eV for 5, 12, 25, and 55 nm GZO ceramics respectively. Further, the ac conductivity was found to obey the universal Jonscher's power law and the power exponent s was found to increase with the increase in temperature. It was also showed that the non-overlapping small polaron tunneling (NSPT) has been the best suited theoretical model to explain the conduction mechanism occurred in GZO ceramics. In addition, increase in co-operative dynamics of mobile ions with increase in grain size was found to favor the enhancement of conductivity.

Small polaron hopping conduction in NiMnO3/NiMn2O4 nano-cotton and its emerging energy application with MWCNT

Self-assembled ilmenite/spinel NiMnO3/NiMn2O4 nano-cotton and it's MWCNT blended composites were synthesized via one-step sol-gel auto combustion and ultra-sonication techniques with a perspective to investigate its dielectric, conduction mechanism and enhanced electrochemical performance to explore its applications as supercapacitor materials and high-temperature energy storage devices. The as-prepared double phase oxides were characterized initially by X-ray diffractometry, FTIR and Raman techniques to ascertain its phase formation and structural information. The FESEM and TEM micrographs reveal the growth of nanoparticles homogeneously and cotton-like morphology over observed space. The EDS elemental analysis and mappings exposed the true stoichiometrical ratios of elemental particles Ni, Mn, O and C and their uniform distribution. The coercivity (264 Oe) and saturation magnetization (1.2 emu/gm.) of MWCNT blended NiMnO3/NiMn2O4 oxides curtailed significantly than NiMnO3/NiMn2O4 which recommends its approach towards the superparamagnetic region. The fitted Nyquist plot (Z'vs.Z'') distinguished the individual contribution of grain and grain boundary and activation energy for grain (0.87 eV) and grain boundary (1.2 eV) was estimated from liner plot of extracted data. The frequency dispersing conductivity spectra was fitted with a modified equation of Jonscher's Power Law proposed by us, σac(ω)=σ0(dc)+A(ω−b)n and temperature dependent frequency exponent (n) and Ln (A) suggests non-overlapping small polaron tunneling (NSPT) model for its conduction mechanism. Displacement of both Ni2+ and Ni3+ ions through the channel like cavities of ilmenite/spinel structure along a, b and c axis provides strong support of the NSPT model. The electrochemical supercapacitor properties of NiMnO3/NiMn2O4 and MWCNT blended NiMnO3/NiMn2O4 were examined in 2 M aqueous KOH solution and excellent capacitive properties were observed for both compounds. Higher capacitance value (1347 F-g−1) and energy density 140 W h kg−1 were obtained at a current density of 5 A g−1 for MWCNT blended NiMnO3/NiMn2O4 with compared to its parent counterparts.

Enhanced electrical properties of CaCu3Ti4O12 ceramics by spark plasma sintering: Role of Zn and Al co-doping

Highly dense CaCu3Ti4O12 (CCTO) ceramics co-doped by ZnO and Al2O3 were synthesized by spark plasma sintering (SPS) at 750 °C for 10 min, and then annealed at 1000 °C for 3 h. The homogeneous microstructures were achieved, and the grain size was suppressed to around 2 μm. Dramatically enhanced electrical properties of CCTO ceramics were obtained when 1 mol% ZnO and Al2O3 were co-doped. The breakdown field was improved to 12.13 kV/cm and the nonlinear coefficient was increased to 6.59, accompanying with a low dielectric loss of 0.02 at around 1 kHz, which were ascribed to the elevation of Schottky barrier height from 0.54 eV to 0.80 eV. Comparing with the pure CCTO sample, the activation energy of grain boundary obtained from the impedance spectra increases from 0.64 eV to 0.92 eV. Additionally, the grain and grain boundary resistance were also discussed based on the Cole-Cole plot, from which the grain boundary resistance was found to be increased significantly from 3.8 × 105 Ω to 4.0 × 106 Ω after co-doping.

Bismuth oxide modified europium and niobium co-doped titanium dioxide ceramics: Colossal permittivity and low dielectric loss design

Colossal permittivity (CP) materials have many important applications in electronics but their development is generally hindered due to the difficulty in achieving a relatively low dielectric loss. In this work, based on the electron-pinned defect-dipole and internal barrier layer capacitance (IBLC) theory, we designed to add Bi2O3 to (Eu0.5Nb0.5)0.01Ti0.9O2 (ENTO) ceramics to obtain high performance CP materials. The dielectric loss can be reduced down to 0.017 at 1 kHz and room temperature, while the permittivity is kept at a relatively high value (2.7 × 104). At the same time, the temperature and frequency stability can also be improved. More importantly, the mechanism of decreasing dielectric loss is studied. It is finding that the decrease of dielectric loss is closely associated with the enhanced localized behavior of conduction process at grain boundary. The addition of Bi2O3 can increase the grain boundary resistance and grain-boundary activation energy of the ceramics, which make the conductive behavior of the grain boundaries more difficult, resulting in decreasing the dielectric loss and improve the temperature stability of the ceramics.

Pyroelectric and impedance studies of the 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Sr0.3)TiO3 ceramics

This work contributes towards the analysis of the pyroelectric behaviour of lead-free pyroelectric 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Sr0.3)TiO3 (BZT-BST) ceramics. The pyroelectric coefficient (3.4 × 10−4 C m−2 K−1 at 303 K) was obtained by the Byer-Roundy method. The pyroelectric figures of merit for current, voltage, detectivity and energy harvesting applications are discussed with respect to possible optimization of these parameters. All the above mentioned figures of merit are dependent on the permittivity and dielectric loss. Hence, impedance analysis was conducted to identify the dominant contributions in permittivity and dielectric loss. The activation energies for bulk and grain boundary are ~1.0 eV and ~1.2 eV, respectively, which indicates presence of mobile oxygen vacancies. The contribution of these processes to the dielectric loss in the temperature range of interest (300–340 K) is, however, very low. The permittivity and the dielectric loss are dominated by a strictly dielectric response resulting from the phase transition in the respective temperature range.

Kinetics and thermodynamics of densification and grain growth: Insights from lanthanum doped zirconia

The effect of dopants (or additives) on sintering is typically addressed from a mechanistic and diffusivity perspective by focusing on how dopants affect those parameters. However, a comprehensive description of sintering needs to address the role of dopants in the thermodynamics of the system, which affects local chemical potentials driving forces and is, therefore, ultimately linked to the mass transport mechanisms themselves by the thermodynamic extremal principle. In this work, Lanthanum doped Yttria-Stabilized-Zirconia (YSZ) sintering was studied from both kinetics and thermodynamic perspectives to demonstrate the need for those complementary analyses to allow proper processing control. La caused inhibition of both grain growth and densification, which was a result of a change of interfacial energies linked to La segregation as well as of the codependence of coarsening and densification on the grain boundary energy. While La caused a modest decrease in the activation energy for densification, surface and grain boundary energies decreased from 0.95 to 0.70 J/m2, respectively, for YSZ, to 0.80 and 0.41 J/m2 for 2 mol% La-YSZ, indicating an increase in sintering stress. The apparent contradiction between the thermodynamic data and the observed densification trend is attributed to the reduced grain growth that trapped the system in a metastable configuration.