Article
Materials Science, Multidisciplinary
Sriram P. Ramkumar, Elizabeth A. Nowadnick
Summary: Layered perovskite oxides are promising platforms for designing novel properties and functionalities, with the ability to tune material properties through controlling octahedral rotation distortions. This study investigates how octahedral rotations respond to pressure in hybrid improper ferroelectrics, revealing the impact of factors such as cation formal charge, tolerance factor, and B-site chemistry on the pressure response. Additionally, the coupling between octahedral rotation and strain order parameters plays a key role in determining the overall pressure response of these materials.
Article
Multidisciplinary Sciences
Maxime Markov, Louis Alaerts, Henrique Pereira Coutada Miranda, Guido Petretto, Wei Chen, Janine George, Eric Bousquet, Philippe Ghosez, Gian-Marco Rignanese, Geoffroy Hautier
Summary: Through analysis of phonon band structures in a high-throughput database, a structural family of anti-Ruddlesden-Popper phases A(4)X(2)O (A=Ca, Sr, Ba, Eu, X=Sb, P, As, Bi) showing ferroelectric and antiferroelectric behaviors is identified. The discovered ferroelectrics belong to the new class of hyperferroelectrics that can polarize even under open-circuit boundary conditions. This structural family includes Eu4Sb2O, which exhibits coupled ferromagnetic and ferroelectric order at the same atomic site, a rare occurrence in materials physics.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Review
Chemistry, Physical
Alessandro Caiazzo, Rene A. J. Janssen
Summary: This review discusses the toolbox and methods used for high efficiency solar cells based on Ruddlesden-Popper perovskites.
ADVANCED ENERGY MATERIALS
(2022)
Article
Multidisciplinary Sciences
Yan Shao, Wei Gao, Hejin Yan, Runlai Li, Ibrahim Abdelwahab, Xiao Chi, Lukas Rogee, Lyuchao Zhuang, Wei Fu, Shu Ping Lau, Siu Fung Yu, Yongqing Cai, Kian Ping Loh, Kai Leng
Summary: In this study, the surface octahedral tilt of exfoliated 2D Ruddlesden-Popper perovskites (RPPs) was directly observed using scanning tunneling microscopy (STM), which was found to agree with theoretical calculations. The surface-enhanced octahedral tilt is correlated to excitonic redshift observed in photoluminescence (PL) and enhances inversion asymmetry and Rashba spin splitting.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Xiangxin Tian, Zhaoxing Hu, Zeliang Gao, Yongzhuan Zhang, Chuanming Li, Hongwei Qi, Xiuping Liu, Rongkun Zheng, Jiangtao Xu, Jingquan Liu
Summary: The quasi two-dimensional Ruddlesden-Popper perovskites have attracted attention for their environmental stability and performance, and the introduction of fluorinated organic cations improves stability. However, the mechanism of fluorination effects requires further investigation.
MATERIALS CHEMISTRY FRONTIERS
(2021)
Article
Nanoscience & Nanotechnology
Soirik Dan, Raja Chakraborty, Amlan J. Pal
Summary: This study introduces a new type of inorganic perovskite material, Cs2PbI2Cl2, with ferroelectric properties suitable for pyro-phototronic devices. Unlike hybrid materials, the ferroelectricity in Cs2PbI2Cl2 is not dependent on the organic component possessing an electric dipole moment, but rather on the distortion-induced twisting and tilting of the 2D-layer-forming octahedra.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Multidisciplinary
Jaye K. Harada, Kenneth R. Poeppelmeier, James M. Rondinelli
Summary: In this study, we propose a strategy to design ferroelectric heteroanionic materials based on the coupling of anion order and octahedral tilts in Ruddlesden-Popper structures. We find that large degrees of octahedral tilting can stabilize different anion orders, and that tilts are primarily driven by covalent interactions. Local out-of-plane polar displacements induced from anion order further stabilize the octahedral tilts through the pseudo-Jahn-Teller effect.
PHYSICAL REVIEW MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Qiang Fu, Mingqian Chen, Qiaohui Li, Hang Liu, Rui Wang, Yongsheng Liu
Summary: By using a selenophene-based spacer, researchers have successfully developed stable and efficient 2D RP perovskite solar cells. They achieved efficient electron extraction and transport by optimizing the perovskite film and using a transport layer. The study shows that the selenophene-based spacer significantly improves the conversion efficiency and stability of 2D RP perovskite solar cells.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
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, Physical
Xiyue Dong, Mingqian Chen, Rui Wang, Qin Ling, Ziyang Hu, Hang Liu, Yufei Xin, Yang Yang, Jian Wang, Yongsheng Liu
Summary: A concept of quantum confinement breaking in 2D perovskites is proposed using organic semiconductor spacers based on theoretical calculation and experimental results. Intensive orbital coupling is found in (BThMA)(2)PbI4, resulting in the breaking of the multiple quantum well structure, while no orbital interactions exist in (BPhMA)(2)PbI4. The (BThMA)(2)MA(n)(-1)Pb(n)I(3)(n)(+1) (n = 5) perovskite-based device exhibits an outstanding power conversion efficiency (PCE) of 18.05%, which is much higher than that of the BPhMA-based device (PCE = 12.69%) and among the best efficiency in 2D PSCs based on long conjugated spacers.
ADVANCED ENERGY MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Hwanhui Yun, Dominique Gautreau, K. Andre Mkhoyan, Turan Birol
Summary: In this study, the structural phase diagram of n = 1 RP Sr2SnO4 was investigated using group theory based symmetry analysis and first-principles calculations. The effects of different dynamical instabilities on symmetry breaking and phase energies were explored, taking into account different boundary conditions. The effect of structural changes on the electronic structure was also addressed, with compressive biaxial strain leading to a wider band gap and lower electron effective mass in Sr2SnO4.
PHYSICAL REVIEW MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Jonghoon Lee, Kyeong-Yoon Baek, Jeongjae Lee, Heebeom Ahn, Yongjin Kim, Hyungbin Lim, Yeeun Kim, Jaeyong Woo, Samuel D. Stranks, Sung Keun Lee, Henning Sirringhaus, Keehoon Kang, Takhee Lee
Summary: Organic metal-halide perovskites (OHPs) are attracting attention as next-generation semiconducting materials, but current doping methods have limitations. This study successfully included a molecular dopant into 2D Ruddlesden-Popper perovskites, increasing electrical current by about 60 times while maintaining a clean film surface. The mechanism of immersion doping, where a solvent molecule facilitates bulk diffusion of the dopant molecule, is provided. This method enables bulk molecular doping in OHPs and can be used to control their electrical properties for electronic and optoelectronic devices.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Inorganic & Nuclear
Wang Luo, Na Wang, Hua-Kai Li, Ze-Jiang Xu, Yan Feng, Xiao-bin Fu, Chao Shi, Heng-Yun Ye, Le-Ping Miao
Summary: In this study, a two-dimensional (2D) Ruddlesden-Popper (RP) type hybrid perovskite ferroelastic material (TFCA)(2)CdCl4 is reported, which exhibits a critical temperature of 402 K and a spontaneous strain of 0.071. The rapid rotating motions of polar rotors lead to fast reorientation of dipoles, resulting in a large dielectric response. The study reveals that the 2D RP hybrid perovskite molecular rotor platform provides a new avenue to explore dynamic functional materials.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Multidisciplinary
Loreta A. Muscarella, Algirdas Ducinskas, Mathias Dankl, Michal Andrzejewski, Nicola Pietro Maria Casati, Ursula Rothlisberger, Joachim Maier, Michael Graetzel, Bruno Ehrler, Jovana Milic
Summary: Layered Dion-Jacobson (DJ) and Ruddlesden-Popper (RP) hybrid perovskites with modular structure are promising for optoelectronic applications. By using mechanical stimuli, their properties can be controlled without changing the composition. This study investigates the structure-property relationships of DJ and RP 2D perovskites under hydrostatic pressure and reveals the changes in lattice and optical properties. Surprisingly, RP and DJ perovskites behave similarly under pressure despite the different spacer molecules. The manipulation of crystal structure affects the optoelectronic properties, and the reversibility of their response expands future application prospects.
ADVANCED MATERIALS
(2022)
Article
Chemistry, Physical
Carlos Mora Perez, Dibyajyoti Ghosh, Oleg Prezhdo, Wanyi Nie, Sergei Tretiak, Amanda Neukirch
Summary: This study investigates the impact of defects on the ground state electronic structure of two-dimensional RP halide perovskites. The research reveals that neutral-type point defects have limited influence on the electronic structure, while donor/acceptor defects introduce deep midgap states that can harm the material's electronic performance. Avoiding halide vacancies and interstitial defects is crucial to maintain positive intrinsic properties and improve device performance in 2D halide perovskite-based applications.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Austin M. Evans, Kelsey A. Collins, Sangni Xun, Taylor G. Allen, Samik Jhulki, Ioannina Castano, Hannah L. Smith, Michael J. Strauss, Alexander K. Oanta, Lujia Liu, Lei Sun, Obadiah G. Reid, Gjergji Sini, Danilo Puggioni, James M. Rondinelli, Tijana Rajh, Nathan C. Gianneschi, Antoine Kahn, Danna E. Freedman, Hong Li, Stephen Barlow, Garry Rumbles, Jean-Luc Bredas, Seth R. Marder, William R. Dichtel
Summary: The bulk conductivity of 2D polymers (2DPs) can be enhanced by controlled n-doping. Optical and transient microwave spectroscopy measurements show that the n-doped 2DPs exhibit desired electronic properties. Density functional theory calculations reveal the main contribution to electronic conductivity in 2DPs. This study provides a new approach for synthesizing 2DPs with specific conductive properties.
ADVANCED MATERIALS
(2022)
Article
Physics, Condensed Matter
Jeffrey Z. Kaaret, Guru Khalsa, Nicole A. Benedek
Summary: We investigate how the structural changes induced by ultrafast optical excitation of infrared-active phonons in LaAlO3 change with hydrostatic pressure using theory and first-principles calculations. Our findings show that the observed structural changes are sensitive to pressure, with the largest changes occurring near the boundary between the cubic perovskite and rhombohedral phases. By defining a figure of merit based on intrinsic materials quantities, we explain our findings and demonstrate that the peak response near the phase boundary is dictated by different microscopic materials properties depending on the phonon mode being excited.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Physics, Multidisciplinary
Quintin N. Meier, Daniel Hickox-Young, Geneva Laurita, Nicola A. Spaldin, James M. Rondinelli, Michael R. Norman
Summary: Higgs and Goldstone modes are widely studied in high-energy and condensed matter physics. In this study, the Leggett mode, a collective mode observed in multiband superconductors, is found to have an analog in crystallographic phase transitions. This discovery sheds new light on the understanding of structural phase transitions.
Article
Materials Science, Multidisciplinary
Jingyang He, Abishek K. Iyer, Michael J. Waters, Sumanta Sarkar, Rui Zu, James M. Rondinelli, Mercouri G. Kanatzidis, Venkatraman Gopalan
Summary: This study reports the successful growth of single crystals of gamma-NaAsSe2 that exhibit a giant second harmonic generation (SHG) susceptibility, similar to commercial AgGaSe2 but with a similar bandgap, making it promising for infrared laser applications.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Chemistry, Physical
Abishek K. Iyer, Jeong Bin Cho, Michael J. Waters, Jun Sang Cho, Benjamin M. Oxley, James M. Rondinelli, Joon I. Jang, Mercouri G. Kanatzidis
Summary: Noncentrosymmetric chalcogenides containing stereochemically active lone pair elements can tune the band gap and enhance the second harmonic generation (SHG) response. These compounds with a three-dimensional structure show significantly improved SHG behavior and are attractive for commercial applications.
CHEMISTRY OF MATERIALS
(2022)
Article
Chemistry, Inorganic & Nuclear
Abbey J. Neer, Joanna Milam-Guerrero, Veronika A. Fischer, Michelle Zheng, Nicole R. Spence, Clayton Cozzan, Mingqiang Gu, James M. Rondinelli, Craig M. Brown, Brent C. Melot
Summary: We conducted a comparative study on the magnetic and crystal chemical properties of two Co2+-containing garnets. It was found that CaY2Co2Ge3O12 and NaCa2Co2V3O12 exhibited different magnetic structures and properties under similar external conditions. Crystal-chemistry analyses and density functional theory calculations were performed to explain these differences based on minor changes in the local environment of the Co ions.
INORGANIC CHEMISTRY
(2022)
Article
Multidisciplinary Sciences
Hari Padmanabhan, Maxwell Poore, Peter K. Kim, Nathan Z. Koocher, Vladimir A. Stoica, Danilo Puggioni, Huaiyu (Hugo) Wang, Xiaozhe Shen, Alexander H. Reid, Mingqiang Gu, Maxwell Wetherington, Seng Huat Lee, Richard D. Schaller, Zhiqiang Mao, Aaron M. Lindenberg, Xijie Wang, James M. Rondinelli, Richard D. Averitt, Venkatraman Gopalan
Summary: This study provides evidence for interlayer magnetophononic coupling in layered magnetic topological insulator MnBi2Te4. The anomalies in phonon scattering intensities across magnetic field-driven phase transitions are observed using magneto-Raman spectroscopy, which is attributed to phonons modulating the interlayer exchange coupling. The signatures of magnetophononic coupling are also observed in the time domain through ultrafast excitation and detection of coherent phonons.
NATURE COMMUNICATIONS
(2022)
Review
Materials Science, Multidisciplinary
Nicole A. Benedek, Michael A. Hayward
Summary: This paper reviews the theoretical, computational, and synthetic literature on hybrid improper ferroelectricity in layered perovskite oxides. Different ferroelectric mechanisms are compared and discussed, and the use of theory and first-principles calculations for elucidation is highlighted. The connections between crystal chemistry and the physical mechanisms of ferroelectricity are emphasized. The experimental literature on hybrid improper ferroelectrics, especially cation-ordered double perovskites, Ruddlesden-Popper, and Dion-Jacobson phases, is surveyed. Preparative routes for synthesizing hybrid improper ferroelectrics and opportunities for expanding this family of materials are also discussed.
ANNUAL REVIEW OF MATERIALS RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Donghoon Shin, Minliang Lai, Yongjin Shin, Jingshan S. S. Du, Liban Jibril, James M. Rondinelli, Chad A. Mirkin
Summary: The stability, reliability, and performance of halide-perovskite-based devices are determined by the structure, composition, and particle size of the device-enabling materials. A new method called evaporation-crystallization polymer pen lithography is used to synthesize and study Cs(0.5)FA(0.5)PbX(3) crystals and discover heterostructure morphology. The heterostructures are formed due to differences in solubility of ions and enthalpic preference for ion segregation, and solid-solution nanocrystals are synthesized to suppress photoinduced anion migration for photostable optoelectronic materials.
ADVANCED MATERIALS
(2023)
Article
Engineering, Mechanical
Akshay Iyer, Suraj Yerramilli, James M. Rondinelli, Daniel W. Apley, Wei Chen
Summary: Engineering design often involves qualitative and quantitative variables. High-dimensional qualitative variables impose a large design cost. We address this challenge by utilizing domain knowledge to infer the effect of unobserved levels. Our method is robust and reduces design cost for problems with high-dimensional qualitative variables.
JOURNAL OF MECHANICAL DESIGN
(2023)
Article
Chemistry, Inorganic & Nuclear
Ming-Li Liang, Matthew Lacroix, Ce Tao, Michael J. Waters, James M. Rondinelli, P. Shiv Halasyamani
Summary: The synthesis and optical properties of noncentrosymmetric (NCS) gamma-Cs2I4O11 were reported, which was obtained through IO4 polyhedral rearrangements from centrosymmetric (CS) beta-Cs2I4O11. Trifluoroacetic acid (TFA) played a key role in the synthesis as a structure-directing agent. The material exhibited strong second-harmonic-generation (SHG) response and was type I phase matchable.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Assael Cohen, Pranab K. Mohapatra, Simon Hettler, Avinash Patsha, K. V. L. V. Narayanachari, Pini Shekhter, John Cavin, James M. Rondinelli, Michael Bedzyk, Oswaldo Dieguez, Raul Arenal, Ariel Ismach
Summary: Conventional epitaxy is essential for semiconductor technology, but there are still unresolved differences in terms of orientation registry and interface chemistry in quasi-vdW epitaxy. This study focuses on the growth of WS2 using metal-organic chemical vapor deposition (MOCVD) and a metal-seeding approach, which allows for the formation of a continuous WO3 layer on a sapphire substrate. The presence of this interfacial layer strongly influences the subsequent growth of the WS2 layer. This work provides insights into the epitaxial growth mechanism and demonstrates the effectiveness of the metal-seeding approach for the growth of other TMDC layers.
Article
Physics, Multidisciplinary
Alexander C. Tyner, Shouvik Sur, Danilo Puggioni, James M. Rondinelli, Pallab Goswami
Summary: In this study, it is discovered that three-dimensional stable Dirac semimetals demonstrate the quantum spin Hall effect, with bound states on n-fold symmetric momentum planes. These planes support the same non-Abelian Berry flux and exhibit identical topological response.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Materials Science, Multidisciplinary
Sean Koyama, James M. Rondinelli
Summary: In this study, a new type of persistent spin texture (PST) material is discovered, called symmetry-assisted PSTs, which can enhance the performance of spintronic devices. Chemical substitution can be used to tune the properties of these materials, such as spin lifetime. Additionally, it is found that existing two-dimensional models are insufficient to fully describe the spin texture state in these materials, indicating the need for higher-order models.
Article
Materials Science, Multidisciplinary
Xue-Zeng Lu, James M. Rondinelli
Summary: Through electronic structure calculations and algebraic representation analysis, we have discovered that high-quality persistent spin textures can be hidden in complex ternary layered and perovskite structures with large electric polarizations, offering potential for future quantum microelectronic devices.