Sürdürülebilir Kalkınma Amaçları
Yazarlar
Yayınlar
- MakaleYalnız künye2026Scopus SJRQ1Compositionally segmented thermoelectric BiSbTe thin films on Cr/Si(100)
Yüzüak, G. Durak; Yüzüak, E.
Compositionally segmented thermoelectric (CS-TE) structures improve thermal energy conversion efficiency across large thermal gradients. However, their increased design complexity complicates performance modeling and optimization. In this study, we fabricate CS-TE BiSbTe thin films on Cr-buffered Si(100) substrates. By adopting a multidisciplinary approach, we aim to broaden the technological applicability and strategic relevance of advanced TE systems. We systematically analyze the influence of deposition pressures (5, 7, and 10 mTorr) on TE performance. Variations in working pressure alter the Bi/Sb atomic ratio in the films, while the Te content remains stable. This enables the controlled formation of CS structures. At 323 K, the power factor (PF) of TE thin films reaches 0.7, 2.4, and 7.3 mW/mK2 under 5, 7, and 10 mTorr deposition conditions, respectively. The Cr-buffered layer significantly improves the electrical conductivity of CS-TE BiSbTe films. We further engineer a p-type single-leg device integrating nanostructured Bi0.35Sb1.65Te3, Bi0.37Sb1.63Te3, and Bi0.4Sb1.60Te3 layers. These materials are optimized to achieve peak TE PF values across a wide temperature range (320 to 500 K) while ensuring robust interfacial adhesion. The CS-TE device generates 3 mW/cm2, showing a 15% improvement over single-composition samples at a 100 K temperature difference.
AtıfScopus3WoS3OpenAlex2
İncele - MakaleYalnız künye2024Scopus SJRQ2Optimizing the thermoelectric performance of Bi-Sb-Te thin films through compositional engineering
Yüzüak, Gizem Durak; Çetin, Mehmet; Yüzüak, Ercüment
The objective of the present investigation was to systematically investigate the structural and thermoelectric (TE) properties of BixSb2-xTe3 thin films with varying content of Bi. We investigated the impact of different atomic percentages of Bi (4, 6, 8 at. %) on the properties of carrier transport and TE performance. In general, the Seebeck coefficient remained consistent across the thin films. For the 8 at. % Bi thin film, the Seebeck coefficient and electrical conductivity were measured at 230 μV/K and 730 S/cm, respectively, at room temperature. These values were more than 20 times greater than the electrical conductivity observed in the thin films with compositions of 6 and 4 at. % Bi. As a result, the Bi-Sb-Te compound exhibited a TE power factor (PF) of 38x10−4 W/mK2 at 40 °C, surpassing the PFs observed in previous compositions. The analysis of surface microstructure, combined with atomic force microscopy and Kelvin probe microscopy images, revealed that the transport of carriers in films with high Bi content was impeded by the size of particles and scattering sites. On the other hand, an augmentation in Bi content promoted the transfer of charge through crystalline regions, hence improving the mobility of carriers and the total electrical conductivity. The aforementioned results emphasize the significant influence of Bi content on the electrical properties of semiconductors and demonstrate the effectiveness of compositional engineering based on Bi content in the development of TE materials with superior performance. The present study investigates the influence of Bi content on the electrical properties of Bi-Sb-Te thin films, demonstrating that compositional adjustments based on Bi content can impact the performance of TE materials. These findings contribute to the understanding of material optimization in the field of TE.
AtıfScopus4WoS5OpenAlex5İncele