Article
Materials Science, Multidisciplinary
H. Sakabayashi, R. Okazaki
Summary: The study shows that the layered cobaltite [Ca2CoO3](0.62)[CoO2] exhibits clear in-plane anisotropy in its transport properties at different temperatures, which can be qualitatively understood by the simple band structure of the triangular lattice of Co ions. Additionally, at high temperatures, the resistivity displays temperature-independent behavior, indicating the presence of hopping conduction of localized carriers.
Article
Materials Science, Multidisciplinary
Alfred Griesser, Thomas Kraus, Oliver Klein, Helmut Karl
Summary: This study successfully grown epitaxial Ca3Co4O9 thin films on YSZ and Ir metallized YSZ buffered single crystalline (001)-Si substrates by pulsed laser deposition, achieving low ASR and low in-plane electrical resistivity of the Ca3Co4O9 thin film.
Article
Chemistry, Physical
Hanhwi Jang, Stanley Abbey, Woo Hyun Nam, Brakowaa Frimpong, Chien Viet Nguyen, Sung-Jae Joo, Ho Sun Shin, Jae Yong Song, Eugene N. Cho, Moohyun Kim, Yeon Sik Jung, Min-Wook Oh
Summary: Despite the focus on tellurides, there is a compelling demand to replace tellurium with selenium due to its scarcity. Silver bismuth diselenide (AgBiSe2, ABS) has been widely studied for thermoelectric applications due to its low thermal conductivity, but its low power factor (PF) has hindered improvements. The introduction of copper into the ABS system has shown to significantly increase the power factor and improve the TE performance, opening up new possibilities for environmentally friendly high-performance TE materials.
JOURNAL OF MATERIALS CHEMISTRY A
(2021)
Article
Chemistry, Physical
Daniel Duarte Ruiz, Caterina Cocchi
Summary: This study used advanced methods to investigate core spectroscopy in LiCoO2 and CoO2, revealing that excitonic effects play a negligible role in the X-ray absorption spectra of these materials. Monitoring the electronic structure of LiCoO2 during the delithiation process is sufficient to capture the evolution of their X-ray absorption signatures.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Uzma Hira, Syed Shahbaz Ali, Shoomaila Latif, Nini Pryds, Falak Sher
Summary: The study demonstrates that dual doping of Na and Mo cations is an effective strategy to improve the high-temperature thermoelectric properties of Ca3Co4O9, leading to enhanced Seebeck coefficient and reduced electrical resistivity and thermal conductivity. The thermoelectric power factor and dimensionless figure of merit obtained for the dual-doped materials are significantly improved compared to the pristine compound, showing great potential for thermoelectric renewable energy applications.
Article
Chemistry, Multidisciplinary
Uzma Hira, Syed Shahbaz Ali, Shoomaila Latif, Nini Pryds, Falak Sher
Summary: Layered structured Ca3Co4O9 shows great potential for thermoelectric renewable energy applications. In this study, dual doping of Na and Mo cations is found to significantly enhance the thermoelectric properties of Ca3Co4O9, with improved Seebeck coefficient, decreased electrical resistivity and thermal conductivity, and higher dimensionless figure of merit.
Article
Chemistry, Multidisciplinary
Mali Zhao, Dohyun Kim, Yongjoon Lee, Ning Ling, Shoujun Zheng, Young Hee Lee, Heejun Yang
Summary: Research on thermoelectricity has mainly focused on the macroscopic scale, but the importance of microscopic structures in emerging thermoelectric materials is increasing, with the manipulation of thermoelectric puddles on the nanometer scale remaining unexplored. By utilizing stacking order and electronic screening in graphene, distinct thermoelectric puddles can be unveiled, and practical thermopower systems with low-dimensional materials can be achieved through lattice symmetry and electronic engineering.
Article
Materials Science, Multidisciplinary
Hua Chen, X. C. Xie
Summary: A detailed study of the Bose-Hubbard model in a p-band triangular lattice reveals two distinct phases in the superfluid regime and a detwined in-plane ferro-orbital order in close proximity to the Mott insulator phase. The analysis suggests a connection between the in-plane ferro-orbital order in the Mott insulator phase and the superfluid phase.
Article
Chemistry, Multidisciplinary
Feng-Xian Bai, Hao Yu, Ya-Kang Peng, Shan Li, Li Yin, Ge Huang, Liu-Cheng Chen, Alexander F. Goncharov, Jie-He Sui, Feng Cao, Jun Mao, Qian Zhang, Xiao-Jia Chen
Summary: This study found that the electrical properties of Bi0.5Sb1.5Te3 can be effectively improved by applying external pressure through inducing an electronic topological transition, resulting in a higher figure of merit at room temperature.
Article
Physics, Multidisciplinary
Jung-Hwa Kim, Darren C. Peets, Manfred Reehuis, Peter Adler, Andrey Maljuk, Tobias Ritschel, Morgan C. Allison, Jochen Geck, Jose R. L. Mardegan, Pablo J. Bereciartua Perez, Sonia Francoual, Andrew C. Walters, Thomas Keller, Paula M. Abdala, Philip Pattison, Pinder Dosanjh, Bernhard Keimer
Summary: Researchers have discovered checkerboard charge order in the FeO2 planes using neutron Larmor diffraction and Fe K-edge resonant x-ray scattering, which disappears at temperatures above 332 K. Stacking disorder of the checkerboard pattern leads to broader superstructure reflections and reduced amplitudes.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Jin Hee Kim, Jae Hyun Yun, Yoo Jang Song, Jong-Soo Rhyee
Summary: The (SnSe)(1.17)(TaSe2) compound exhibits both thermoelectric and superconducting properties, with anisotropic characteristics observed from XRD and electrical resistivity measurements. Results from density functional theory (DFT) calculations indicate electronic charge transfer, while the compound's thermoelectric properties also show significant anisotropy.
CURRENT APPLIED PHYSICS
(2021)
Article
Physics, Condensed Matter
Yingna Han, Xing Xu, Wandong Xing, Rong Yu, Fanyan Meng
Summary: The recent discovery of stable FeO2 under high pressure has sparked great interest in the field of materials science, indicating the existence of the 4+ oxidation state of late transition metals in binary oxides. Using density functional theory calculations, PbO2-type CoO2 and pyrite-type NiO2 were predicted, which can be synthesized under specific high pressures. Mechanical and dynamical stabilities of these compounds were confirmed, with PbO2-CoO2 being half metallic and pyrite-NiO2 being semiconducting according to band structures and densities of states.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2021)
Article
Chemistry, Multidisciplinary
Linming Zhou, Cheng Dai, Peter Meisenheimer, Sujit Das, Yongjun Wu, Fernando Gomez-Ortiz, Pablo Garcia-Fernandez, Yuhui Huang, Javier Junquera, Long-Qing Chen, Ramamoorthy Ramesh, Zijian Hong
Summary: Order-disorder transitions in the polar vortex phase of [Pb(Zr0.4Ti0.6)O-3](n)/(SrTiO3)(n) superlattices were investigated using phase-field simulations. An antiorder vortex state was discovered for short-period superlattices with a large tensile substrate strain. Increasing the periodicity leads to an antiorder to disorder transition. By mediating the substrate strain, the order-disorder-antiorder transition can be engineered in short-period superlattices.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Chemistry, Physical
Yangfan Cui, Xiaojun Wang, Shuai Duan, Xin Chen, Xiaobing Liu
Summary: This article introduces a new semiconducting phase in TaS3, called the C2/m phase, which has beneficial multivalley band dispersions for electronic transport and a unique nano-pore structure that reduces thermal conductivity. It shows potential high-performance thermoelectric capability.
JOURNAL OF MATERIOMICS
(2022)
Article
Chemistry, Physical
K. P. Mohamed Jibri, J. Archana, M. Navaneethan, S. Harish
Summary: Among the various thermoelectric oxide materials, perovskites offer more flexibility to adjust the thermoelectric parameters through cation deficiency and substitution. In this study, the effect of A-site cation deficiency and Sr-substitution on the thermoelectric properties of LaCoO3 ceramic was investigated. The electrical conductivity and power factor were found to increase with La deficiency and Sr-substitution, resulting in an improved thermoelectric performance with a maximum power factor value of 78 mu W m(-1) K-2 for the LCO2 composition at 403 K.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
