Heat capacity and dielectric properties of multiferroics Bi1 − x Gd x FeO3 (x = 0–0.20)

Thermophysical properties of BiFeO3, Bi0.91Nd0.09FeO3, and BiFe0.91Mn0.09O3 multiferroics at high temperatures

“…2a and in the table, a partial substitution of neodymium for bismuth in BiFeO 3 increased and a partial substitution of manganese for iron in this ferrite decreased its transition temperature from the antiferromagnetic to the paramagnetic state (the antiferromagnetic-paramagnetic phase transition), which agrees well with the data of [2,9,11,13,16,21]. The solid solution also demonstrated the decrease in the heat of this transition, which is more noticeable in the solid solution containing Mn.…”

“…The heat capacity of bismuth orthoferrite BiFeO 3 and its solid solutions with rareearth metals Bi 0.95 Re 0.05 FeO 3 (Re = La, Eu, Ho), and Bi 1 -x Gd x FeO 3 (0.05 < x < 0.20) were studied in [9][10][11]. The thermal expansion of ferrites BiFeO 3 and Bi 0.95 La 0.05 FeO 3 were studied in [9,12] and the thermal diffusion and the thermal conductivity of these multiferroics at elevated temperatures were described in [13].…”

Vacancy-Induced Temperature-Dependent Thermal and Magnetic Properties of Holmium-Substituted Bismuth Ferrite Nanoparticle Compacts

“…The model parameters for the nanoparticles are obtained and listed in Table S4. However, the fitted values of D 1 are at least 3 orders of magnitude higher than that of previously reported values, , which is not physical for the current heat capacity scenario. Therefore, the excess part of the current work cannot be explained in terms of the Schottky anomaly for the three-level energy states of BFO and BHFO.…”

“…Indeed, ∼50% of the measured heat capacity is dominated by excess heat capacity, ΔC p at 800 K (Figures 6c and S14). Previous reports suggest that such excess heat capacity of BFO and rare-earth doped BFO system can be interpreted in terms of Schottky anomaly for three-level energy states, 17,57 which can be expressed as follows 17,58…”

“…Indeed, ∼50% of the measured heat capacity is dominated by excess heat capacity, Δ C p at 800 K (Figures c and S14). Previous reports suggest that such excess heat capacity of BFO and rare-earth doped BFO system can be interpreted in terms of Schottky anomaly for three-level energy states, , which can be expressed as follows , where Δ E 1 and Δ E 2 are the energy barriers that separate three different occupying energy states, k B is the Boltzmann constant, ϑ is the number of moles, R is the universal gas constant, and D 1 and D 2 are the ratios of the degeneracy orders of the levels. The measured heat capacities, as shown in Figures c and S15, were fitted using both eqs and .…”