Article
Chemistry, Multidisciplinary
Jingxian Zhong, Yan Sun, Bowen Liu, Chao Zhu, Yang Cao, Encheng Sun, Kaiyue He, Wei Zhang, Kan Liao, Xiaoyong Wang, Zheng Liu, Lin Wang
Summary: Ruddlesden-Popper perovskites exhibit a rich variety of phases due to their mixed organic cations and variable layer numbers. Utilizing a one-pot CVD synthesis method, different layer distributions of Ruddlesden-Popper phases can be achieved within a single perovskite nanosheet, with the optical properties being highly dependent on the nanosheet thickness.
Article
Chemistry, Multidisciplinary
Gill M. Biesold, Shuang Liang, Brent K. Wagner, Zhitao Kang, Zhiqun Lin
Summary: The study successfully designed a flow reactor to continuously produce high-quality two-dimensional RP perovskite nanoplatelets. The synthesis rate of the flow reactor was found to be over 8 times higher than batch synthesis, offering the potential for large-scale production.
Article
Chemistry, Multidisciplinary
Yunseong Choi, Donghwan Koo, Gyujeong Jeong, Ungsoo Kim, Hyungmin Kim, Fuzhi Huang, Hyesung Park
Summary: In this study, a highly oriented butylammonium RP perovskite surface passivation layer was developed via vacuum deposition. The passivation layer reduced the trap density of the bulk perovskite and enhanced charge transport, resulting in a power conversion efficiency of 21.4% for vacuum-processed perovskite solar cells. This passivation strategy offers potential for the development of efficient, stable, and scalable perovskite solar cells.
ENERGY & ENVIRONMENTAL SCIENCE
(2022)
Review
Chemistry, Multidisciplinary
Rui Liu, Xin Hu, Maoxia Xu, Haorong Ren, Hua Yu
Summary: This article summarizes the research progress and application prospects of layered low-dimensional halide perovskites (LDPs), and expounds on the merits and drawbacks of two common LDPs materials from their chemical structure, physicochemical properties, and photovoltaic performance. Furthermore, the synthesis and implementation of LDPs thin films and devices, as well as their optoelectronic properties, are reviewed. Possible strategies to achieve high-performance LDPs solar cells are discussed.
Article
Multidisciplinary Sciences
Chao Yang, Yi Wang, Daniel Putzky, Wilfried Sigle, Hongguang Wang, Roberto A. Ortiz, Gennady Logvenov, Eva Benckiser, Bernhard Keimer, Peter A. van Aken
Summary: This study investigates the microstructural characteristics and electronic structure of a NdNiO3 film grown by layer-by-layer molecular beam epitaxy. The researchers observe different configurations of Ruddlesden-Popper (RP) faults through aberration-corrected scanning transmission electron microscopy and spectroscopy. They also demonstrate the relationship between the valence change of nickel and strain and structure variation.
Article
Chemistry, Multidisciplinary
Junsang Cho, Preethi S. Mathew, Jeffrey T. DuBose, Prashant Kamat
Summary: 2D lead halide perovskites with tunable bandgap and enhanced chemical stability are useful for designing optoelectronic devices. Reducing dimensionality can increase resistance to light-induced ion migration, but also decreases the efficiency of halide ion segregation and segregation rate constant, leading to a decrease in charge-carrier lifetime.
ADVANCED MATERIALS
(2021)
Article
Multidisciplinary Sciences
G. Fabbris, D. Meyers, Y. Shen, V. Bisogni, J. Zhang, J. F. Mitchell, M. R. Norman, S. Johnston, J. Feng, G. S. Chiuzbaian, A. Nicolaou, N. Jaouen, M. P. M. Dean
Summary: Ruddlesden-Popper and reduced Ruddlesden-Popper nickelates are potential substitutes for high-temperature superconducting cuprates, but the extent of their similarity has been contested. Resonant inelastic x-ray scattering (RIXS) has been crucial in studying their electronic and magnetic excitations, but inconsistent results among different samples and the absence of publicly available data have hindered detailed comparisons. To address this, we present open RIXS data on La4Ni3O10 and La4Ni3O8.
Article
Chemistry, Multidisciplinary
Qian Cheng, Boxin Wang, Gaosheng Huang, Yanxun Li, Xing Li, Jieyi Chen, Shengli Yue, Kang Li, Hong Zhang, Yuan Zhang, Huiqiong Zhou
Summary: This study investigates the residual strain in a two-dimensional Ruddlesden-Popper perovskite film and finds that the spacer cations contribute to the residual strain. By strain relaxation, the film quality is improved, leading to enhanced efficiency and good stability in unstable environments.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Zhen Yu Zhang, Guo Ping Wang
Summary: Time-domain study of coherent acoustic phonons in nanomaterials provides dynamic and unparalleled insight into their mechanical and structural features. The acoustic breathing mode of resonant coherent phonons (RCP) in nanoscale RP perovskite films is reported, which shows that RCP oscillation can be used as a novel and non-destructive approach for quantitatively evaluating the decomposition of moisture-exposed RP perovskite. These results reveal the decisive effect of structural geometry on acoustic performances in perovskite nanomaterials.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Linfang Yan, Junjie Ma, Pengwei Li, Shuangquan Zang, Liyuan Han, Yiqiang Zhang, Yanlin Song
Summary: This article summarizes the recent advances in carrier behavior of 2D Ruddlesden-Popper perovskite solar cells (PSCs) and provides guidelines and strategies for enhancing carrier transport.
ADVANCED MATERIALS
(2022)
Review
Multidisciplinary Sciences
Junlin Lu, Chunhua Zhou, Weijian Chen, Xin Wang, Baohua Jia, Xiaoming Wen
Summary: This review introduces the recent progress on the edge states of 2D RP perovskites, including their origin, optoelectronic properties, and current debates. It is of great significance for the development of optoelectronic devices.
Article
Energy & Fuels
Yi Wei, Baoquan Chen, Fan Zhang, Yuyang Tian, Xichuan Yang, Bin Cai, Jijun Zhao
Summary: The study aimed to simultaneously enhance the stability and efficiency of perovskite solar cells by tuning the organic components in 2D Ruddlesden-Popper perovskites (2D-RPPs). By investigating the influence of different cations on film properties and device performance, the authors achieved a high efficiency of 16.15% for the (FPEA)(2)(FA)(8)Pb9I28 solar cell. Notably, the film exhibited good humidity stability and enhanced thermal stability, maintaining 95% of its efficiency after 2112 hours of exposure to ambient air. This study demonstrates that strategically designing organic compositions can lead to improved performance of 2D-RPPs, paving the way for commercialization of 2D-RPP devices.
Article
Chemistry, Physical
Aleksandr Bamburov, Yevgeniy Naumovich, Dmitry D. Khalyavin, Aleksey A. Yaremchenko
Summary: This study investigated the possibility of introducing cation vacancies into the Ln sublattice of perovskite-related Ruddlesden-Popper nickelates. The results showed that the concentration of cation vacancies in the A sublattice of the Ruddlesden-Popper structure is very low, and the introduction of vacancies enhances the diffusivity of A-site cations and destabilizes the structure. However, the nominal cation deficiency has no effect on the electrical conductivity and oxygen permeability of the ceramics.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Shuai Zhao, Cui Chen, Huan Li, Wenrui Zhang
Summary: By using first-principles calculations, the migration mechanism of alkali ions in RP antiperovskites was investigated, showing that alkali interstitials have lower migration barriers than vacancies and play a crucial role in improving the ionic conductivity.
NEW JOURNAL OF CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Zhiyuan Xu, Ling Li, Xiyue Dong, Di Lu, Rui Wang, Wan-Jian Yin, Yongsheng Liu
Summary: CsPbI3-based 2D Ruddlesden-Popper perovskites with thiophene-based aromatic spacers exhibit improved phase stability and achieve a record efficiency of 16.00%. These devices maintain high efficiency even after long-term storage and exposure to high temperatures.
Article
Physics, Multidisciplinary
Kohei Yamamoto, Tomoyuki Tsuyama, Suguru Ito, Kou Takubo, Iwao Matsuda, Niko Pontius, Christian Schuessler-Langeheine, Makoto Minohara, Hiroshi Kumigashira, Yuichi Yamasaki, Hironori Nakao, Youichi Murakami, Takayoshi Katase, Toshio Kamiya, Hiroki Wadati
Summary: The relationship between the magnetic interaction and photoinduced dynamics in antiferromagnetic perovskites is investigated in this study. The findings show that time-resolved resonant soft x-ray scattering can be used to observe the ultrafast quenching of magnetic ordering and the efficient channel for spin-order manipulation through optically induced charge transfer.
NEW JOURNAL OF PHYSICS
(2022)
Article
Multidisciplinary Sciences
Shingo Kaneta-Takada, Miho Kitamura, Shoma Arai, Takuma Arai, Ryo Okano, Le Duc Anh, Tatsuro Endo, Koji Horiba, Hiroshi Kumigashira, Masaki Kobayashi, Munetoshi Seki, Hitoshi Tabata, Masaaki Tanaka, Shinobu Ohya
Summary: Researchers have achieved efficient spin-charge current conversion by using a two-dimensional electron gas (2DEG) formed at the interface between SrTiO3 (STO) and oxide insulating layers. The introduction of a strongly correlated perovskite oxide LaTiO3+delta (LTO) interlayer has enabled giant spin-to-charge current conversion efficiencies, highlighting the potential of oxide interfaces for spin-orbitronics applications.
NATURE COMMUNICATIONS
(2022)
Article
Physics, Applied
Keisuke Ide, Naoto Watanabe, Takayoshi Katase, Masato Sasase, Junghwan Kim, Shigenori Ueda, Koji Horiba, Hiroshi Kumigashira, Hidenori Hiramatsu, Hideo Hosono, Toshio Kamiya
Summary: In this study, LEDs were fabricated on glass substrates using amorphous oxide semiconductor materials as emission layers. Rare-earth-doped AOS films were employed, and the LEDs emitted clear red, green, and pink luminescence even in the ambient environment. Resonance photoelectron spectroscopy revealed different emission mechanisms for each rare-earth dopant. This study provides opportunities for the advancement of flexible display technologies in harsh environments.
APPLIED PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Tsukasa Katayama, Shishin Mo, Akira Chikamatsu, Yuji Kurauchi, Hiroshi Kumigashira, Tetsuya Hasegawa
Summary: In this study, GdBaCo2O6 epitaxial films were successfully synthesized and reversible transformation between x = 5.5 and 6 phases was achieved via low-temperature redox reactions. The x = 6 film exhibited ferromagnetic and metallic behavior below 110 K and semiconducting behavior above. The ferromagnetic interaction between Co3.5+ and Gd3+ contributed to the magnetization and the half-metallicity of the film.
CHEMISTRY OF MATERIALS
(2023)
Article
Physics, Multidisciplinary
Takemi Kato, Yongkai Li, Kosuke Nakayama, Zhiwei Wang, Seigo Souma, Fumihiko Matsui, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Yugui Yao, Takafumi Sato
Summary: The study found that Nb substitution can increase the superconducting transition temperature and reduce the CDW temperature in Cs(V1-xNbx)(3)Sb-5. Nb substitution adjusts the position of the bands in the band structure, resulting in a decrease in the CDW gap and T-CDW. This study reveals the important role of the SP density of states in stabilizing the CDW, and suggests that the enhancement of superconductivity by Nb substitution is achieved through the expansion of the electron pocket and the recovery of the density of states at the Fermi level.
PHYSICAL REVIEW LETTERS
(2022)
Article
Multidisciplinary Sciences
Kohei Fujiwara, Yasuyuki Kato, Hitoshi Abe, Shun Noguchi, Junichi Shiogai, Yasuhiro Niwa, Hiroshi Kumigashira, Yukitoshi Motome, Atsushi Tsukazaki
Summary: Amorphous semiconductors are widely used in electronic and energy-conversion devices. This study reveals that the short-range crystalline order in amorphous Fe-Sn films contributes to anomalous electrical and magneto-thermoelectric properties. This finding sheds light on the topology of amorphous materials and may enable the realization of functional topological amorphous electronic devices.
NATURE COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
M. Ohno, T. C. Fujita, Y. Masutake, H. Kumigashira, M. Kawasaki
Summary: Researchers have successfully synthesized two new metallic layered oxide compounds [BinOn+d]-[RhO2] (n = 2, 3) by pulsed laser deposition and subsequent annealing, and revealed dimensionality-dependent electrical transport behavior. This achievement paves the way for further exploration of novel layered oxide compounds.
Article
Materials Science, Multidisciplinary
Kazuki Nagai, Masato Anada, Kazuhiro Kowa, Miho Kitamura, Hiroshi Kumigashira, Hiroo Tajiri, Yusuke Wakabayashi
Summary: It has been found that oxide films thinner than a few unit cells are often insulating, and the Anderson localization supported by low dimensionality is one of the major mechanisms for this behavior. To distinguish the effects of randomness from dimensionality, the structural fluctuation and average structure of LaNiO3 thin films on LaAlO3 substrates were examined as a function of thickness. Surface x-ray diffraction experiment revealed little difference in average atomic position and atomic occupancy between 2 to 5 u.c. thick samples, with the main difference observed in the atomic displacement parameters. This suggests that structural fluctuation plays a role in interfacial transport properties, which is often neglected in discussions of oxide interface physics.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Tatsuhiko Kanda, Daisuke Shiga, Asato Wada, Ryotaro Hayasaka, Yuuki Masutake, Naoto Hasegawa, Miho Kitamura, Kohei Yoshimatsu, Hiroshi Kumigashira
Summary: Quantized states in strongly correlated oxide nanostructures are crucial for designing quantum devices in future electronics. In situ ARPES measurements in SrTi1-xVxO3 reveal that the electron mean free path is a key parameter for controlling and designing quantized states in these structures.
COMMUNICATIONS MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Takuto Nakamura, Toru Nakaya, Yoshiyuki Ohtsubo, Hiroki Sugihara, Kiyohisa Tanaka, Ryu Yukawa, Miho Kitamura, Hiroshi Kumigashira, Keiichiro Imura, Hiroyuki S. Suzuki, Noriaki K. Sato, Shin-ichi Kimura
Summary: The electronic structure changes on the SmS surface under K doping are investigated using core-level photoelectron spectroscopy and angle-resolved photoelectron spectroscopy. The results show that the mean valence of Sm on the surface increases from nearly divalent to trivalent states with increasing K deposition. This carrier-induced valence transition (CIVT) from Sm2+ to Sm3+ is opposite to the conventional electron doping. The excess electrons from K atoms transfer to S sites, and the liberated electrons from Sm3+ ions due to CIVT are trapped around the Sm3+ ions like local excitons.
Article
Materials Science, Multidisciplinary
Asuka Honma, Daichi Takane, Seigo Souma, Yongjian Wang, Kosuke Nakayama, Miho Kitamura, Koji Horiba, Hiroshi Kumigashira, Takashi Takahashi, Yoichi Ando, Takafumi Sato
Summary: By utilizing angle-resolved photoemission spectroscopy, we observed the band structure of three types of single-q antiferromagnetic domains at the surface of NdSb. We found that different surface domains exhibit different surface state formations and proposed that these surface states arise from symmetry breaking at the surface and the antiferromagnetic order.
Article
Materials Science, Multidisciplinary
D. Shiga, X. Cheng, T. T. Kim, T. Kanda, N. Hasegawa, M. Kitamura, K. Yoshimatsu, H. Kumigashira
Summary: Through in situ photoemission spectroscopy, the changes in the electronic structure of Cr-doped VO2 films on TiO2 substrates were investigated. The phase diagram of CrxV1-xO2 was obtained, showing the influence of strain effect on the metal-insulator transition temperature. The spectroscopic investigations revealed the changes in energy gap and V 3d states, as well as the existence of Mott insulating phase without V-V dimerization at high doping concentration.
Article
Chemistry, Multidisciplinary
Kohei Yoshimatsu, Hiroshi Kumigashira
Summary: High-quality metastable lambda-phase trititanium pentoxide films were successfully grown on substrates via pulsed-laser deposition at very high growth temperature. These films directly formed on substrates without any detectable transient layers, containing almost single domains with very low fraction of rotational domains. The successful synthesis of these metastable films enables the utilization of their rich functionalities.
CRYSTAL GROWTH & DESIGN
(2022)
