Review
Materials Science, Multidisciplinary
Akun Liang, Robin Turnbull, Daniel Errandonea
Summary: The goal of this review is to provide a comprehensive overview of the high-pressure behavior of iodates and their technological applications. Multiple characterization techniques, along with density functional theory calculations, are used to study the phenomena observed in iodates under external compression. The presence of lone electron pairs of iodine atoms is found to play a crucial role in the high-pressure behavior of iodates, affecting the character of iodine-oxygen bonds and causing nonlinear physical properties.
PROGRESS IN MATERIALS SCIENCE
(2023)
Article
Energy & Fuels
Haowei Xu, Qiang Zhang, Longbing Yi, Shaolin Huang, Hao Yang, Yanan Li, Zhe Guo, Haoyang Hu, Peng Sun, Xiaojian Tan, Guo-qiang Liu, Kun Song, Jun Jiang
Summary: A study investigates the use of pressure to suppress interfacial resistance in Bi2Te3-based thermoelectric generators (TEGs). Through the establishment of a theoretical model and derivation of explicit expressions, the relationship between maximum output power, conversion efficiency, and interfacial resistivity is determined. Experimental results demonstrate that by applying suitable pressure, interfacial resistivity can be reduced and conversion efficiency can be improved, providing strong support for the fabrication of high-performance TEGs.
Article
Chemistry, Multidisciplinary
Jacob Manzi, Ariel E. E. Weltner, Tony Varghese, Nicholas McKibben, Mia Busuladzic-Begic, David Estrada, Harish Subbaraman
Summary: This paper demonstrates the use of plasma-jet printing (PJP) to deposit thermoelectric nanoflakes onto flexible substrates at room temperature, with substantial improvements in material adhesion and flexibility observed. The printed films exhibit electrical conductivity of 2.5 x 10(3) S m(-1) and a power factor of 70 mu W m(-1) K-2 at room temperature. This advancement in plasma jet printing promotes not only the development of energy harvesting but also large-scale flexible electronics and sensors for space and commercial applications.
Article
Materials Science, Multidisciplinary
Dongmei Liu, Chunying He, Lan Chen, Wanlu Li, Yanli Zu
Summary: The study investigated the third-order nonlinear optical properties and optical limiting performances of Bismuth telluride/reduced graphene oxide composites at different laser wavelengths. The results showed lower limiting thresholds, indicating the potential application of these composites as optical limiting materials.
Article
Cardiac & Cardiovascular Systems
Agnes Ho, Carol Y. Cheung, Jason S. Wong, Yuzhou Zhang, Fang Yao Tang, Ka Wai Kam, Alvin L. Young, Li Jia Chen, Patrick Ip, Tien Y. Wong, Chi Pui Pang, Clement C. Tham, Jason C. Yam
Summary: This study investigated the independent and synergistic effects of hypertensive BP and obesity on retinal vasculature in young children. Findings suggest potential synergistic or additive effects for both hypertensive BP and obesity on retinal vasculature in children.
JOURNAL OF THE AMERICAN HEART ASSOCIATION
(2021)
Article
Engineering, Electrical & Electronic
Fang Wu, Wei Wang
Summary: An n-type polycrystalline Bi2Te3 bulk sample with nanostructure was successfully fabricated by melt spinning combined with high-pressure sintering. The sample showed improved thermoelectric performance due to the nanograin microstructure embedded in the matrix.
JOURNAL OF ELECTRONIC MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Yao Lu, Yi Zhou, Wu Wang, Mingyuan Hu, Xiege Huang, Dasha Mao, Shan Huang, Lin Xie, Peijian Lin, Binbin Jiang, Bin Zhu, Jianghe Feng, Jianxu Shi, Qing Lou, Yi Huang, Jianmin Yang, Jinhong Li, Guodong Li, Jiaqing He
Summary: Room-temperature bismuth telluride (Bi2Te3) thermoelectrics show good pliability and high power factors in flexible films, which are exfoliated from single crystals. The staggered-layer structure in the films promotes stress propagation and maintains good electrical conductivity without affecting carrier transport, resulting in superior thermoelectric performance. These flexible thermoelectric films offer paradigms for wearable electronics and insights into structure-property manipulation in inorganic semiconductors.
NATURE NANOTECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Heng Zhang, Daniel T. Yimam, Sytze de Graaf, Jamo Momand, Paul A. Vermeulen, Yingfen Wei, Beatriz Noheda, Bart J. Kooi
Summary: Strain engineering has attracted significant interest as a method to control functional properties. Recent research on heterostructures based on Bi2Te3, Sb2Te3, and GeTe has shown potential for a different type of strain engineering due to long-range mutual straining. The study reveals a fast relaxation process in the mica/Bi2Te3 system and long-range strain retention in GeTe and Sb2Te3 grown on or with Bi2Te3. Immediate strain relaxation by plastic deformation was observed, ruling out an elastic model for strain relaxation.
Article
Chemistry, Physical
O. Gomis, R. Vilaplana, E. Perez-Gonzalez, J. Ruiz-Fuertes, P. Rodriguez-Hernandez, A. Munoz, D. Errandonea, A. Segura, D. Santamaria-Perez, P. Alonso-Gutierrez, M. L. Sanjuan, I. M. Tiginyanu, V. V. Ursaki, F. J. Manjon
Summary: Optical absorption measurements were performed on two phases (defect stannite and defect chalcopyrite) of the ordered-vacancy compound ZnGa2Se4. The direct bandgap energy of both phases exhibited a non-linear pressure dependence with a blueshift up to 10 GPa and a redshift at higher pressures. The different behavior of the phases in these pressure ranges was discussed in relation to pressure-induced order-disorder processes at cation sites. Measurements on downstroke after increasing pressure to 22 GPa showed a decrease in the direct bandgap energy compared to the original samples, indicating the formation of different disordered phases on decreasing pressure.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Tong Wang, Si -Min Xue, Ting Song, Lin Ma, Zi-Jiang Liu, Xiao-Wei Sun
Summary: The structural, electronic, and optical properties of MoS2 under high pressure were investigated using first-principles calculations. Among the 12 MoS2 structures considered, the 2R1-MoS2 and 3Hb-MoS2 were identified as stable structures. The 2R1-MoS2 transformed from a semiconductor to a metal, while the metallicity of 3Hb-MoS2 increased under pressure. The optical properties of MoS2 were significantly enhanced and red-shifted in the low-energy region with increasing pressure.
CHEMICAL PHYSICS LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Yubing Xing, Kechen Tang, Jiang Wang, Kai Hu, Yani Xiao, Jianan Lyu, Junhao Li, Yutian Liu, Peng Zhou, Yonggao Yan, Dongwang Yang
Summary: Wearable thermoelectric generators (w-TEGs) convert thermal energy into electrical energy, improving the usage time and efficiency of electronic devices. Through finite element simulation, a high-performance thermoelectric generator was designed and made into a wearable thermoelectric module. The study found that higher convective heat transfer coefficient (h) on the cold-end and longer thermoelectric leg length lead to better power generation performance of the device in typical wearable scenarios.
APPLIED SCIENCES-BASEL
(2023)
Article
Materials Science, Multidisciplinary
Gilberto Rodrigues-Junior, Thais Chagas, Rafael Reis, Paulo Victor Sciammarella, Celso I. Fornari, Paulo H. O. Rappl, Eduardo Abramof, Rogerio Magalhaes-Paniago, Angelo Malachias
Summary: The presence of edge/surface states protected by bulk topology is a key feature of topological insulator materials. This study investigates the effect of magnetic atoms on topologically protected surface states by doping europium (Eu) into bismuth telluride thin films. The results show that higher Eu concentrations lead to the appearance of protrusions and clusters on the film surface, while lower Eu concentrations maintain the presence of surface states.
Article
Materials Science, Multidisciplinary
Subhash Nimanpure, Animesh Pandey, Guruvandra Singh, Bhanu Pratap Singh, Dibakar Roy Chowdhury, Young Uk Jeong, Rina Sharma, Sudhir Husale, Mukesh Jewariya
Summary: The study fabricated Bi2Te3 topological insulator thin film on metallic multi wall carbon nanotubes flexible paper and characterized it using terahertz-time domain spectroscopy, revealing properties of absorption, conductance, and conductivity. Broad band absorption, linear conductance below 3.0 meV, and optical conductivity in the range of 0.02-2.0 THz were observed in the thin film.
Article
Chemistry, Multidisciplinary
Jing Zhou, Jianghe Feng, Hao Li, Duo Liu, Guojuan Qiu, Feng Qiu, Juan Li, Zhong-Zhen Luo, Zhigang Zou, Rong Sun, Ruiheng Liu
Summary: The carrier concentration in n-type Bi2Te3-based thermoelectric material is stabilized by high-energy refinement and hot-pressing, combined with SbI3 doping and hot deformation, resulting in optimized carrier concentration and high texture degree. The peak figure of merit (zT) of 1.14 is achieved for Bi2Te2.7Se0.3 + 0.05 wt.% SbI3 sample with a bending strength of 100 Mpa. Additionally, a thermoelectric cooling device consisting of n-type Bi2Te2.7Se0.3 + 0.05 wt.% SbI3 and commercial p-type Bi0.5Sb1.5Te3 legs generates a large maximum temperature difference (Delta T-max) of 85 K at a hot-side temperature of 343 K.
Article
Chemistry, Multidisciplinary
Tae Jin Yoo, Wan Sik Kim, Kyoung Eun Chang, Cihyun Kim, Min Gyu Kwon, Ji Young Jo, Byoung Hun Lee
Summary: A graphene photodetector decorated with Bi2Te3 nanowires demonstrated high gain and wide bandwidth window. The photoconductive gain was significantly improved compared to a graphene/Bi2Te3 nanoplate junction, and the position of photocurrent generation was investigated. By utilizing low bandgap Bi2Te3 nanowires and a graphene junction, the photoresponsivity was increased effectively.
Article
Chemistry, Physical
Eduardo Martinez Castellano, Javier Yeste, Manuel Abuin, Maria del Carmen Martinez-Tomas, Oleksii Klymov, Vicente Munoz-Sanjose, Miguel Montes Bajo, Adrian Hierro
Summary: The integration of thin Cd(Zn)O films on GaAs is demonstrated to have high optical performance and functionality in the mid-IR. This opens up possibilities for the development of future hybrid Cd(Zn)O/GaAs technology.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
Maksym Yermakov, Roman Pshenychnyi, Anatoliy Opanasyuk, Yuriy Gnatenko, Oleksii Klymov, Maria del Carmen Martinez-Tomas, Vicente Munoz-Sanjose
Summary: This paper investigates the influence of the Mg/Zn molar concentration ratio in the precursor on the structural, optical, and chemical properties of Cu2MgxZn1-xSnS4 films. The results show that replacing zinc with magnesium improves the quality of the solid solution and reduces the band gap in the concentration range of y < 0.3. Successful incorporation of Mg in thin layers is confirmed.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Crystallography
Alfonso Munoz, Placida Rodriguez-Hernandez
Summary: In this study, we used the Density Functional Theory to analyze the structural, electronic, dynamic, and elastic properties of Ca3Y2Ge3O12 garnet under hydrostatic pressure. We reported the equation of state, compressibility, and structural evolution of the compound, as well as the change in infrared, silent, and Raman frequencies and their pressure coefficients. We also studied the dependence of elastic constants and mechanical and elastic properties on pressure. Our findings indicate that the garnet becomes mechanically unstable at 45.7 GPa, and soft phonons are present at 34.4 GPa, indicating dynamical instability above this pressure.
Article
Materials Science, Multidisciplinary
Robin Turnbull, Javier Gonzalez-Platas, Akun Liang, Dequan Jiang, Yonggang Wang, Catalin Popescu, Placida Rodriguez-Hernandez, Alfonso Munoz, Jordi Ibanez, Daniel Errandonea
Summary: We conducted an experimental and theoretical high-pressure study on Na3Bi(IO3)6 and found a first-order pressure-induced phase transition at around 9.5 GPa. This phase transition resulted in a doubling of the primitive cell volume and a decrease in the volume per formula unit. The transition also led to a decrease in the indirect electronic bandgap and revealed highly anisotropic compressibility of the ambient pressure phase.
RESULTS IN PHYSICS
(2023)
Article
Chemistry, Physical
Natalia Majewska, Alfonso Munoz, Ru-Shi Liu, Sebastian Mahlik
Summary: This study compares the changes in the luminescence properties of Ga2O3:Cr3+ modified by Al or Sc ion substitution (chemical pressure) and hydrostatic pressure. Ga2-x Al x O3:Cr3+ exhibits the same behavior under chemical and mechanical pressure, while Ga2-x Sc x O3:Cr3+ shows different behavior. Al substitution affects the crystal volume but not the chemical bond angles in the Cr3+ local environment, whereas Sc ions cause lattice distortion and influence the chemical bond lengths and angles. The energy structure diagrams of the d(3) configuration of Cr3+ ion as a function of pressure are calculated by considering the pressure dependence of the Racah parameters. It is suggested that the method and diagrams presented in this paper should be used for interpreting high-pressure experiments involving Cr3+ and other transition metals.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Physical
O. Gomis, R. Vilaplana, E. Perez-Gonzalez, J. Ruiz-Fuertes, P. Rodriguez-Hernandez, A. Munoz, D. Errandonea, A. Segura, D. Santamaria-Perez, P. Alonso-Gutierrez, M. L. Sanjuan, I. M. Tiginyanu, V. V. Ursaki, F. J. Manjon
Summary: Optical absorption measurements were performed on two phases (defect stannite and defect chalcopyrite) of the ordered-vacancy compound ZnGa2Se4. The direct bandgap energy of both phases exhibited a non-linear pressure dependence with a blueshift up to 10 GPa and a redshift at higher pressures. The different behavior of the phases in these pressure ranges was discussed in relation to pressure-induced order-disorder processes at cation sites. Measurements on downstroke after increasing pressure to 22 GPa showed a decrease in the direct bandgap energy compared to the original samples, indicating the formation of different disordered phases on decreasing pressure.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Physical
Alka B. Garg, David Vie, Placida Rodriguez-Hernandez, Alfonso Munoz, Alfredo Segura, Daniel Errandonea
Summary: Through diffuse reflectivity measurements in InNbO4, ScNbO4, YNbO4, and eight rare-earth niobates, it is found that Tauc plot analysis gives erroneous estimates of the bandgap energy, while accurate results are obtained considering excitonic contributions using the Elliot-Toyozawa model. The bandgaps are 3.25 eV for CeNbO4, 4.35 eV for LaNbO4, 4.5 eV for YNbO4, and 4.73-4.93 eV for SmNbO4, EuNbO4, GdNbO4, DyNbO4, HoNbO4, and YbNbO4. The results indicate that rare-earth substitution has little effect on the bandgap energy and that they have the largest bandgap due to the mainly contribution from Nb 4d and O 2p orbitals near the Fermi level. YNbO4, CeVO4, and LaNbO4 have smaller bandgaps because of the contribution from rare-earth atom 4d, 5d, or 4f orbitals to the states near the Fermi level.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Crystallography
Estelina Lora da Silva, Mario C. Santos, Placida Rodriguez-Hernandez, Alfonso Munoz, Francisco Javier Manjon
Summary: We performed an ab initio study on Sb2S3, Sb2Se3, and Bi2S3 sesquichalcogenides under hydrostatic pressures up to 60 GPa. We investigated the possibility of formation of C2/m, C2/c, the disordered Im-3m, and the I4/mmm phases in these compounds based on recent experiments. Our calculations revealed that the C2/c phase is not energetically favorable in any of the three compounds. The C2/m phase is also unfavorable for Sb2S3 and Bi2S3, but energetically favorable for Sb2Se3 above 10 GPa. The I4/mmm and the disordered Im-3m structures become competitive and energetically more stable than the C2/m phase at pressures beyond 30 GPa. The dynamical stabilities of these structural phases at high pressures are discussed.
Article
Materials Science, Multidisciplinary
A. L. J. Pereira, J. A. Sans, O. Gomis, D. Santamaria-Perez, S. Ray, A. Godoy-Jr, A. S. da Silva-Sobrinho, P. Rodriguez-Hernandez, A. Munoz, C. Popescu, F. J. Manjon
Summary: In this study, the structural and vibrational properties of C-type Y2O3 under hydrostatic compression were investigated through a combination of high-pressure X-ray diffraction, Raman scattering experimental measurements, and ab initio theoretical calculations. The results confirmed the phase transition sequence of C-type to B-type to A-type on the upstroke and A-type to B-type on the downstroke. This finding is consistent with other rare-earth sesquioxides with similar ionic radii as Y. The good agreement between experimental and calculated results allowed for a more detailed understanding of the effect of pressure on rare-earth sesquioxides.
RESULTS IN PHYSICS
(2023)
Article
Chemistry, Inorganic & Nuclear
Indrani. G. Shanmugapriya, Supratik Mukherjee, Alfonso Munoz, Ganapathy Vaitheeswaran, Srinivasan Natarajan
Summary: In this study, compounds belonging to the palmierite structure with different transition metal substitutions were prepared and their optical properties were examined. The substitution of transition metals was found to reduce the overall band gap, and band structure calculations supported this finding by providing orbital information.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2023)
Article
Physics, Condensed Matter
Rahma Khediri, Dalila Hammoutene, Kamel Kassali, P. Rodriguez-Hernandez, Alfonso Munoz
Summary: This paper presents an ab initio study on the properties of Ti2InN, including structural, elastic, vibrational, and thermodynamic properties, using the Density Functional Theory. The study analyzes the evolution of structural properties under hydrostatic pressure, the pressure dependence of vibrational properties, elastic constants, and mechanical properties. It also investigates the thermodynamic properties in a temperature range from 0 to 1000 K.
COMPUTATIONAL CONDENSED MATTER
(2023)
Article
Materials Science, Multidisciplinary
Tania Garcia-Sanchez, Samuel Gallego-Parra, Akun Liang, Jose Luis Rodrigo-Ramon, Alfonso Munoz, Placida Rodriguez-Hernandez, Javier Gonzalez-Platas, Juan angel Sans, Vanesa Paula Cuenca-Gotor, Hussien H. Osman, Catalin Popescu, Veaceslav Ursaki, Ion M. Tiginyanu, Daniel Errandonea, Francisco Javier Manjon
Summary: The effect of pressure on the structural, vibrational, and optical properties of room-temperature crystallized PbGa2S4 is investigated. X-ray diffraction, Raman scattering, and optical-absorption measurements are conducted at pressures beyond 20 GPa, and the results are compared to ab initio calculations and related compounds. The study reveals a partially reversible pressure-induced decomposition of PbGa2S4 into a mixture of Pb6Ga10S21 and Ga2S3 above 15 GPa, offering a route for the high-pressure synthesis of Pb6Ga10S21, which is isostructural to the stable Pb6In10S21 compound.
JOURNAL OF MATERIALS CHEMISTRY C
(2023)
Article
Chemistry, Physical
Alka B. Garg, David Vie, Placida Rodriguez-Hernandez, Alfonso Munoz, Alfredo Segura, Daniel Errandonea
Summary: Diffuse reflectivity measurements were performed on InNbO4, ScNbO4, YNbO4, and eight rare-earth niobates. Tauc plot analysis provided erroneous estimates of the bandgap energy for InNbO4 and ScNbO4, while accurate results were obtained using the Elliot-Toyozawa model considering excitonic contributions. The bandgaps were found to be 3.25 eV for CeNbO4, 4.35 eV for LaNbO4, 4.5 eV for YNbO4, and 4.73-4.93 eV for SmNbO4, EuNbO4, GdNbO4, DyNbO4, HoNbO4, and YbNbO4. The influence of rare-earth substitution on bandgap energy was minimal, and the largest bandgap resulted from the dominance of Nb 4d and O 2p orbitals near the Fermi level.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
