Article
Chemistry, Physical
Jiangtao Fan, Gang He, Zhenzhu Cao, Yongfan Cao, Zhen Long, Zhanggui Hu
Summary: Through the synthesis of a system of acceptor Gd3+ and donor Ta5+ co-doped (Gd0.5Ta0.5)xTi1-xO2 (GTTOx, x = 0, 0.01, 0.02, 0.04, 0.06) ceramics, dielectric response is enhanced. A colossal permittivity (CP, 2.65 x 104@1 kHz, 2.37 x 104@1 MHz), a very low dielectric loss (tano, 0.007@1 kHz, 0.03@1 MHz), good stability of frequency (20-106 Hz) and temperature (RT-250 degrees C, D epsilon 0 (T)/epsilon 030 < +/- 15%, at 1 kHz) were achieved simultaneously in GTTO0.01 ceramic. The main reasons for the improved dielectric properties are the synergistic effect of the electron pinning defect-dipole (EPDD) model, the internal blocking layer capacitance (IBLC) mechanism, and electrode response. This work provides a promising approach for the design of defect-related high-performance giant dielectric ceramics.
JOURNAL OF MATERIOMICS
(2023)
Article
Materials Science, Ceramics
Yasumin Mingmuang, Narong Chanlek, Viyada Harnchana, Prasit Thongbai
Summary: This study investigates the effects of Sn4+ doping concentration on the crystal structure, microstructure, dielectric behavior, and electrical properties of SnxTa(0.025)Ti(0.975-x)O(2) ceramics. It is found that adjusting the Sn4+ doping concentration can improve the dielectric properties of co-doped TiO2.
CERAMICS INTERNATIONAL
(2023)
Article
Chemistry, Multidisciplinary
Nateeporn Thongyong, Prasit Thongbai, Pornjuk Srepusharawoot
Summary: The origins and mechanisms of dielectric responses in co-doped TiO2 materials with Ni2+ and Nb5+ were explored through theoretical and experimental investigations. The introduction of oxygen vacancies by Ni2+ doping and the generation of free electrons by Nb5+ doping resulted in the formation of complex defect dipoles that contributed to the dielectric responses. Experimental results showed a significant dielectric response at room temperature due to the presence of defect dipoles and grain boundary/surface barrier layer capacitor effects, which increased with higher doping levels. However, in a temperature range where the grain boundary/surface barrier layer effects were suppressed, the dielectric response decreased with increased doping.
Article
Materials Science, Ceramics
Jinqiu Liu, Yuechan Song, Wenwen Wu, Xingang Wang, Quan Zhou, Gaoyun Niu, Peng Liu
Summary: A series of textured ceramics with different compositions were sintered in a nitrogen environment after magnetic slip casting. The textured ceramics exhibited high permittivity, low dielectric loss, and suitable temperature coefficient, which make them suitable for electronic devices and high-density energy storage. The microstructure evolution of the sintered ceramics under a magnetic field led to improved dielectric properties.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Materials Science, Ceramics
Tiantian Li, Wenjun Cao, Jinsong Wang, Yingtang Zhang, Chunchang Wang
Summary: (In + Nb)-doped Cex(In0.5+Nb0.5)1-xO2 (with x = 0, 0.005, 0.05, and 0.1) ceramics were prepared using a conventional solid-state method. The dielectric properties of the ceramics were studied at temperatures ranging from 3 to 475 K and frequencies ranging from 102 to 106 Hz. All doped samples exhibited a colossal permittivity behavior, with the sample at x = 0.005 showing the best frequency stability. Two thermally activated relaxations contributed to the colossal permittivity behavior: a low-temperature polaron relaxation (R1) caused by electron hopping between Ce3+ and Ce4+ ions, and a high-temperature dipole relaxation (R2) caused by the oxygen-vacancy-dopant defect pair.
CERAMICS INTERNATIONAL
(2023)
Article
Materials Science, Multidisciplinary
Ku Noor Dhaniah Ku Muhsen, Rozana Aina Maulat Osman, Mohd Sobri Idris
Summary: This study investigates the dielectric behavior and microstructural analysis of (Nb, La) co-doped TiO2 ceramic. The presence of secondary phase LaNbTiO6 affects the properties of the ceramic, and different materials and sintering temperatures lead to different results.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2022)
Article
Engineering, Electrical & Electronic
Fengchao Peng, Xin Liao, Yong Pu, Dachuan Zhu
Summary: The appropriate doping of Sb2O3 can promote grain coarsening in TiO2 varistor ceramics, but excessive doping inhibits grain growth. The sintering process oxidizes Sb3+ ions to Sb5+ ions, releasing free electrons and decreasing resistivity, leading to a continuous decline in breakdown voltage with increasing Sb2O3 doping content. The relative dielectric constant and nonlinear coefficient initially increase with Sb2O3 doping, reaching maximum values at 0.2 mol% before decreasing, but dielectric loss is negatively affected and the ratio of Sb3+/Sb5+ should be controlled for optimal performance.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Longhai Yang, Wenjie Gao, Jiaxing Wang, Chunxiang He, Gaili Yue, Tao Zhang
Summary: Li-doped Bi2/3Cu3Ti4O12 ceramics were successfully prepared, and the effect of Li doping on the crystal structure and dielectric properties was investigated. Li doping improved the dielectric constant and reduced the dielectric loss in the mid-frequency range. The dielectric response at different frequencies was found to originate from different regions within the ceramics.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2023)
Article
Materials Science, Ceramics
Porntip Siriya, Narong Chanlek, Pornjuk Srepusharawoot, Viyada Harnchana, Prasit Thongbai
Summary: A triple-doped (Ga1/2Nb1/2)(0.1)Ti0.9O2 ceramic with acceptor-donor co-doping of Al3+ exhibits improved giant dielectric properties. The ceramic shows homogeneous dispersion of all dopants inside the grains and partially segregated dispersion of Ga3+ along the grain boundaries. The improved dielectric properties are attributed to internal and surface barrier-layer capacitor effects produced by the Ga3+ and Al3+ dopants, respectively, and semiconducting grains resulting from Nb5+ doping ions.
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
(2022)
Article
Materials Science, Ceramics
Menglong Wang, Jialing Xie, Keying Xue, Lingxia Li
Summary: The effects of co-doping Eu3+ and Ta5+ ions on the crystal structure and dielectric properties of rutile TiO2-based ceramics were systematically studied through experiments and calculations. It was found that the introduction of heterogeneous ions caused structural deformation and oxygen vacancies, affecting the functional performance of the material. The colossal permittivity behavior of the co-doped ceramics is primarily attributed to the interface barrier layer capacitor effect, while the secondary phase with Ta element influences the grain boundary activation energy and dielectric performance.
CERAMICS INTERNATIONAL
(2021)
Article
Materials Science, Multidisciplinary
Theeranuch Nachaithong, Narong Chanlek, Pairot Moontragoon, Pornjuk Srepusharawoot, Prasit Thongbai
Summary: Ti1-x(Co1/3Ta2/3)xO2 ceramics prepared by a mixed oxide method exhibit low dissipation factor and excellent temperature stability, with high dense sintered-ceramics having low tan delta of 0.015-0.043 and high dielectric permittivities of 7.0-9.1 x 104 at 1 kHz. The microstructure of the ceramics shows homogeneous distribution of the dopants. Impedance spectroscopy reveals the electrically heterogeneous microstructure and the contributions of intrinsic and extrinsic factors to dielectric relaxations. The high permittivity is attributed to intrinsic defect dipoles and extrinsic internal barrier layer capacitor (IBLC) effects, while the low tan delta is primarily caused by the IBLC effect associated with high resistance and defect dipoles.
RESULTS IN PHYSICS
(2023)
Article
Engineering, Electrical & Electronic
Jagabandhu Pradhan, H. K. Mallick, M. P. K. Sahoo, A. K. Pattanaik
Summary: This study investigates the structure, microstructure, and dielectric properties of La/Gd co-doped SrTiO3 ceramics, revealing that increasing doping concentration can enhance the dielectric constant. The enhanced dielectric behavior is mainly attributed to the segregation of secondary phases and localized transport.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Chemistry, Physical
Kai Zhang, Lingxia Li, Menglong Wang, Weijia Luo, Wenbo Wang
Summary: By adjusting donor ions doping and the distribution of oxygen vacancies, BaTiO3 ceramics with colossal permittivity and high insulation resistivity can be achieved, providing a technical basis for the preparation of single-layer microchip capacitors.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Biochemistry & Molecular Biology
Theeranuch Nachaithong, Narong Chanlek, Pairot Moontragoon, Prasit Thongbai
Summary: (Co, Nb) co-doped rutile TiO2 nanoparticles were prepared with low dopant concentrations, exhibiting high dielectric permittivity and low loss tangent. Impedance spectroscopy revealed that the ceramics are electrically heterogeneous, with interfacial polarization at internal insulating layers contributing to the low loss tangent.
Article
Multidisciplinary Sciences
Nguyen Xuan Duong, Ji-Soo Jang, Min-Hyoung Jung, Jong-Seong Bae, Chang Won Ahn, Jong Sung Jin, Kyuwook Ihm, Gyehyeon Kim, So Yeon Lim, Jongmin Lee, Dang Duc Dung, Soonil Lee, Young -Min Kim, Sanghan Lee, Sang Mo Yang, Changhee Sohn, Ill Won Kim, Hu Young Jeong, Seung-Hyub Baek, Tae Heon Kim
Summary: Significant enhancements of low-frequency dielectric responses in oxygen-deficient oxide ceramics are demonstrated through specific treatments under humid environments. Ultrahigh dielectric permittivity is achieved by hydrogenation when Ni-substituted BaTiO3 ceramics are exposed to high humidity. Thermal annealing can restore the initial low polarizability state of the ceramics. The reversible control of dielectric relaxation characteristics in oxide ceramics allows for potential applications in highly efficient dielectric-based humidity sensors.
Article
Materials Science, Multidisciplinary
Mengjiao Dong, Liyun Liao, Chensheng Li, Yingxiao Mu, Yanping Huo, Zhong-Min Su, Fushun Liang
Summary: This study investigates the influence of the polarity of polymer matrices on persistent room-temperature phosphorescence (pRTP). It is discovered that intense phosphorescence emission can be achieved in highly polar matrices such as polyacrylic acid (PAA). The dipole-dipole interaction between the polar fluorophore and polar matrix is proposed to stabilize the excited state and facilitate the generation of efficient room-temperature phosphorescence emissions.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Han-Jiang Yang, Weijia Xiang, Xiangzhou Zhang, Jin-Yun Wang, Liang-Jin Xu, Zhong-Ning Chen
Summary: This article reports a 2D copper(I)-based cluster material for X-ray imaging, which exhibits ultra-high spatial resolution, high photoluminescence efficiency, and low detection limit. The material shows excellent linear response to X-ray dose rates and light output, and has the best spatial resolution among reported lead-free metal halide hybrids.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Review
Materials Science, Multidisciplinary
Taek Joon Kim, Sang-hun Lee, Dayeong Kwon, Jinsoo Joo
Summary: Donor-acceptor heterostructures using organic-inorganic halide perovskites, two-dimensional transition metal dichalcogenides, pi-conjugated organic small/macro molecules, and quantum dots are promising platforms for exciton-based photonics and optoelectronics. Hetero-interlayer excitons and hetero-intermolecular excitons formed through optical and/or electrical charge transfer in various heterostructures are important quasi-particles for light emission, detection, and harvesting systems.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Liemao Cao, Xiaohui Deng, Zhen-kun Tang, Rui Tan, Yee Sin Ang
Summary: We investigate the interface properties between WSi2N4 and Mo2B, O-modified Mo2B, and OH-modified Mo2B nanosheets. We find that WSi2N4 and Mo2B form n-type Schottky contacts, while functionalizing Mo2B with O and OH leads to the formation of both n-type and p-type ohmic contacts with WSi2N4. Additionally, we demonstrate the emergence of quasi-ohmic contact with ultralow lateral Schottky barrier and zero vertical interfacial tunneling barriers in Mo2B(OH)2-contacted WSi2N4.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Ga Eun Kim, Hae-Jin Kim, Heesuk Jung, Minwoo Park
Summary: This study presents a solution to the commercialization challenges of flexible LEDs based on MAPbBr(3) by incorporating polyurethane and an In-Ga-Zn-Sn liquid alloy. The designed devices showed high flexibility, efficiency, and durability, with improved electron injection and reduced defects, making them promising for next-generation displays.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Tao Shen, Zeng Wu, Zhen Jiang, Dongsheng Yan, Yan Zhao, Yang Wang, Yunqi Liu
Summary: Sidechain engineering is an important molecular design strategy for tuning the solid-state packing and structural ordering of conjugated polymers. The effects of sidechain direction on the optoelectronic properties of polymers and device performance were systematically investigated in this study. The results demonstrate that tuning the sidechain substitution direction can effectively improve the molecular structure and light absorption properties of polymers, providing new insights for the rational design of functional polymers.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Lotte Clinckemalie, Bapi Pradhan, Roel Vanden Brande, Heng Zhang, Jonathan Vandenwijngaerden, Rafikul Ali Saha, Giacomo Romolini, Li Sun, Dirk Vandenbroucke, Mischa Bonn, Hai I. Wang, Elke Debroye
Summary: In this study, a facile strategy using a non-conductive polymer was proposed to fabricate stable, pinhole-free thick films. The effect of introducing a second phase into CsPbBr3 perovskite crystals on their photophysical properties and charge transport was investigated. The dual phase devices exhibited improved stability and more effective operation at higher voltages in X-ray detection.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Jingye Zou, Shenglan Hao, Pascale Gemeiner, Nicolas Guiblin, Omar Ibder, Brahim Dkhil, Charles Paillard
Summary: When rare-earth ions are embedded in a ferroelectric material, their photoluminescence can serve as an all-optical probe for temperature, electric field, and mechanical stimulus. However, the impact of ferroelectric phase transitions on photoluminescence is not well understood. In this study, we demonstrate changes in the photoluminescence of green emission bands during critical ferroelectric transitions in an Er-doped BaTiO3 material. We also find that the intensity ratio and wavelength position difference of sub-peaks provide information on the phase transitions.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Jiangchao Han, Daming Zhou, Wei Yang, Chen Lv, Xinhe Wang, Guodong Wei, Weisheng Zhao, Xiaoyang Lin, Shengbo Sang
Summary: Rare type-II spin-gapless semiconductors (SGSs) have attracted increasing attention due to their unique spin properties. In this study, the interface contacts and spin transport properties of different devices composed of VSi2P4 ferromagnetic layers were investigated. The results show that VSi2P4 is a promising material for designing vertical van der Waals heterostructures with a giant tunnel magnetoresistance (TMR) in spintronic applications.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Tianqi Zhao, Renagul Abdurahman, Qianting Yang, Ruxiangul Aiwaili, Xue-Bo Yin
Summary: In this study, we designed and prepared Cr and Ba-doped gamma-Ga2O3 nanoparticles to achieve near-infrared emission and enhance the emission intensity. The emission mechanism was proposed based on the trap depth, band gap, and energy levels of Cr ions. The ratiometric temperature sensing and encryption information transfer demonstrated the potential applications of this technology.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Shuvankar Gupta, Jyotirmoy Sau, Manoranjan Kumar, Chandan Mazumdar
Summary: In this study, a new spin-gapless semiconductor material CoFeMnSn is reported, and its stable structure and spin-polarized band structure are determined through experimental realization and theoretical calculations. The compound exhibits a high ferromagnetic transition temperature, making it excellent for room temperature applications. The nearly temperature-independent resistivity, conductivity, and carrier concentration of the compound, adherence to the Slater-Pauling rule, and the high intrinsic anomalous Hall conductivity achieved through hole doping further confirm its spin-gapless semiconductor nature. Additionally, the compound's SGS and topological properties make it suitable for spintronics and magneto-electronics devices.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Ikumi Aratani, Yoji Horii, Yoshinori Kotani, Hitoshi Osawa, Hajime Tanida, Toshiaki Ina, Takeshi Watanabe, Yohko F. Yano, Akane Mizoguchi, Daisuke Takajo, Takashi Kajiwara
Summary: In this study, two-dimensional arrays of single-molecule magnets (SMMs) based on metal-organic frameworks (MOFs) were systematically modified through Langmuir-Blodgett methods and chemical modifications. The introduction of bulky alkoxide groups induced structural changes and perpendicular magnetic anisotropy. This research provides a promising strategy for the construction of high-density magnetic memory devices using molecular spintronics.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Zonghao Lei, Houhe Dong, Lijie Sun, Bing Teng, Yanfei Zou, Degao Zhong
Summary: Researchers have successfully developed four different up-conversion phosphors based on the Eulytite-type host Ba3Yb(PO4)(3). The optical temperature sensing properties of these phosphors were thoroughly investigated, and it was found that Ba3Yb(PO4)(3):Tm/Er/Ho showed potential for optical temperature measurement applications.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
C. Roncero-Barrero, M. A. Carvajal, J. Ribas-Arino, I. de P. R. Moreira, M. Deumal
Summary: This study computationally investigates the conductivity of four isostructural compounds with different Se contents, and reveals the parameters that define their conductivity in stable organic radical materials. The results provide insights into the influence of Se content on the conductivity and highlight the importance of considering multiple parameters in understanding the trends in conductivity.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)
Article
Materials Science, Multidisciplinary
Remi Arras, Kedar Sharma, Lionel Calmels
Summary: In this study, we investigated the interplay between structural defects in NiFe2O4, showing that the complex formed by a Ni-Oh/Fe-Td-cation swap and a neutral oxygen vacancy is more stable than these two isolated defects, and significantly reduces the width of the minority-spin band gap.
JOURNAL OF MATERIALS CHEMISTRY C
(2024)