Article
Physics, Applied
Kristian Berland, Ole Martin Lovvik, Rasmus Tranas
Summary: Using hybrid functional calculations, promising thermoelectric properties were identified in some compounds, suggesting the potential of reassessing band gaps and band structures of compounds to discover more potential thermoelectric materials.
APPLIED PHYSICS LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Rodrick Kuate Defo, Efthimios Kaxiras, Steven L. Richardson
Summary: The study calculated the hyperfine tensors of group-IV impurity-vacancy color centers using density functional theory, showing good agreement with experimental results and indicating the presence of a Jahn-Teller distortion in these color centers.
Article
Thermodynamics
K. Strzalkowski
Summary: The review discusses the thermal properties of selected II-VI binary, ternary, and quaternary semiconductors, including thermal diffusivity, heat capacity, and thermal conductivity. An analysis of thermal conductivity versus composition diagrams of ternary mixed crystals was conducted, revealing the contribution of lattice disorder to the total resistivity of the crystals. The use of different detection methods and modification of experimental systems were highlighted to adapt the photopyroelectric method for the thermal characterization of II-VI crystals.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Materials Science, Multidisciplinary
Pingping Han, Jingjing Min, Zaiping Zeng, Christos S. Garoufalis, Sotirios Baskoutas, Yu Jia, Zuliang Du
Summary: This study investigates the electronic and excitonic properties of blue-emitting colloidal quantum dots within group II-VI, with a focus on quantum confinement and surface ligand effects. It reveals size-dependent energy gaps governed by quantum confinement effects and predicts a switching of symmetry character at ultrasmall sizes for all quantum dots, leading to linearly polarized band-edge excitonic emission. The research also explores the surface passivation mechanism of inorganic chloride ligand and its effects on exciton characteristics.
Article
Chemistry, Physical
Dongyu Liu, Carlos Mora Perez, Andrey S. Vasenko, Oleg V. Prezhdo
Summary: Lead-free double perovskites have low efficiencies due to defects that act as charge recombination centers. By applying unsupervised machine learning, it was found that Br vacancies create deep hole traps, and doping with In can maintain shallow traps.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Review
Chemistry, Multidisciplinary
Mingfa Peng, Zhen Wen, Xuhui Sun
Summary: Flexible photodetectors with good bendability, foldability, and stretchability, as well as light weight, have attracted wide attention in wearable electronics. II-VI semiconductor nanostructures have emerged as promising candidates for flexible photodetectors due to their unique characteristics. This review summarizes the recent progress and applications of low-dimensional II-VI semiconductors based flexible photodetectors in wearable electronics.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Physical
Beatriz G. del Rio, Brandon Phan, Rampi Ramprasad
Summary: In this study, a machine learning model is proposed to emulate the essence of density functional theory (DFT) by mapping the atomic structure to the electronic charge density and predicting other properties. This model bypasses the computational cost of solving the central Kohn-Sham equation and maintains chemical accuracy.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Physics, Multidisciplinary
I. N. Yakovkin, N. Petrova
Summary: The study reveals that spin-orbit coupling significantly affects the band structures of heavy IV-VI semiconductors, potentially leading to band inversion for topological insulator formation. However, the absence of surface states providing metallicity in thin films raises doubts about the formation of topological crystalline insulators in IV-VI compounds.
Article
Chemistry, Physical
Marek Maciaszek, Vytautas Zalandauskas, Rokas Silkinis, Audrius Alkauskas, Lukas Razinkovas
Summary: In this work, the newly developed Strongly Constrained and Appropriately Normed (SCAN) family of meta-GGA density functionals is tested for selected color centers in diamond. The results show that the SCAN family of functionals can significantly improve the calculated energies of optical transitions and the description of adiabatic potential energy surfaces, making it a promising alternative for studying color centers in solids.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
Quoc Duy Ho, Martin Castillo
Summary: In this study, the intrinsic defects in ZB ZnS were investigated using an optimized hybrid functional, which successfully explained the origin of deep-blue emission in ZB ZnS.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Engineering, Chemical
Wentao Zhu, Xiuming Yu, Yuting Deng, Jinhui Yang, Jinchi Lin, Zhui Tian, Shuibo Xie, Bin Yang
Summary: In this study, a cellulose/sericite hybrid aerogel was prepared for uranium-contaminated wastewater treatment. The aerogel demonstrated high adsorption capacity, stability, interference resistance, and chemical stability.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Review
Optics
Yong Zhang
Summary: The translation is about the crystalline properties of organic-inorganic hybrid materials, classifying them into four levels based on their deviation from the strict definition of crystals. It discusses the different levels of crystallinity and defects in these materials, and provides a brief review on II-VI based hybrids, comparing them with their inorganic counterparts and other hybrids. The future studies of these hybrids are also mentioned.
JOURNAL OF LUMINESCENCE
(2022)
Review
Chemistry, Multidisciplinary
Mathias Micheel, Raktim Baruah, Krishan Kumar, Maria Waechtler
Summary: This review discusses recent advances in the self-assembly of colloidal semiconductor nanocrystals into functional thin films with precise control over order and orientation. It provides a comprehensive overview of characterization methods used in the study of such ordered materials, and focuses on the two most promising methods of gas-liquid interfacial self-assembly and electric field driven deposition to generate superstructures with defined thickness, order, and orientation. The review also explores the relationship between superstructure and properties, specifically charge migration through the film and radiative processes, as well as addressing challenges and open questions in the field.
ADVANCED MATERIALS INTERFACES
(2022)
Article
Crystallography
Roman S. Stepanov, Pavel I. Marland, Alexander V. Kolobov
Summary: In this study, the effect of compositional and structural disorder on the band structure and electronic properties of 2D In(Ga)Se(Te) alloys was investigated using first principles modeling. The results showed that a random distribution of indium and gallium cations led to a noticeable decrease in the band gap, while a random cation distribution in In(Ga)Te resulted in metallization. Changes in the arrangement of chalcogens led to significant changes in the band gap, but no changes in topology were observed. Additionally, compression along the c axis had a significant effect on the band gap of both alloys.
Article
Multidisciplinary Sciences
Zhenyue Wu, Shunning Li, Yasmin Mohamed Yousry, Walter P. D. Wong, Xinyun Wang, Teng Ma, Zhefeng Chen, Yan Shao, Weng Heng Liew, Kui Yao, Feng Pan, Kian Ping Loh
Summary: Researchers synthesized a two-dimensional organic-inorganic hybrid material with ferroelectric properties and achieved tunable ferroic orders through intercalation chemistry, providing new possibilities for engineering the ferroic and elastic properties of materials.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Mao-Hua Du, Jiaqiang Yan, Valentino R. Cooper, Markus Eisenbach
Summary: This study investigates the defect formation and dopant incorporation in MnBi(2)Te(4) and MnBi(4)Te(7) through systematic density functional theory calculations, revealing that internal heterostructure induces large-size-mismatched antisite defects and substitutional dopants. Te-rich growth conditions can reduce bulk free electron density, while Na doping is proposed as an effective way to pin the Fermi level for observing surface quantum transport. The findings suggest strategies for defect engineering and doping in MnBi(2)Te(4), MnBi(4)Te(7), and related magnetic topological insulators.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Yingqi Wang, Songhao Guo, Hui Luo, Chenkun Zhou, Haoran Lin, Xuedan Ma, Qingyang Hu, Mao-hua Du, Biwu Ma, Wenge Yang, Xujie Lu
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2020)
Article
Multidisciplinary Sciences
Artem Musiienko, Jindrich Pipek, Petr Praus, Mykola Brynza, Eduard Belas, Bogdan Dryzhakov, Mao-Hua Du, Mahshid Ahmadi, Roman Grill
Article
Chemistry, Inorganic & Nuclear
Hadiah Fattal, Tielyr D. Creason, Cordell J. Delzer, Aymen Yangui, Jason P. Hayward, Bradley J. Ross, Mao-Hua Du, Daniel T. Glatzhofer, Bayrammurad Saparov
Summary: A new zero-dimensional hybrid organic-inorganic halide, RInBr4, has been investigated for its bright-blue emission and high photoluminescence quantum yield.
The organic component is responsible for the observed blue emission of the hybrid material.
This novel hybrid indium bromide demonstrates significantly improved environmental stability, paving the way for potential applications in light emission.
INORGANIC CHEMISTRY
(2021)
Article
Instruments & Instrumentation
Lakshmi Soundara Pandian, Matthew Loyd, Mao-Hua Du, Edgar van Loef, Guido Ciampi, Luis Stand, Mariya Zhuravleva, Merry Koschan, Jarek Glodo, Charles Melcher, Kanai Shah
Summary: This paper reports on the scintillation properties of TlSr2I5 doped with Eu2+, a high-resolution scintillator for gamma-ray spectroscopy. The X-ray excited emission of Eu2+ doped TlSr2I5 features a broad emission band peaking between 460-470 nm, with a light yield of 72,000 ph/MeV and an energy resolution of 2.8%.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2021)
Article
Instruments & Instrumentation
Edgar van Loef, Urmila Shirwadkar, Lakshmi Soundara Pandian, Guido Ciampi, Luis Stand, Mao-Hua Du, Merry Koschan, Matthew Loyd, Mariya Zhuravleva, Charles Melcher, Kanai Shah
Summary: This paper investigates the crystal growth, DFT calculations, and scintillation properties of Tl(3)LnCl(6) and TlLn(2)Cl(7) (Ln = Y, Gd) crystals. These crystals belong to the Nesohalides and Phyllohalides families with varying crystal structures, and exhibit light yields typically in the range of 35,000-40,000 ph/MeV.
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
(2021)
Article
Materials Science, Multidisciplinary
Rumeng Zhao, Xiuli Yang, Hongliang Shi, Mao-Hua Du
Summary: The study finds that V-Sb and V-S defects are dominant in Sb2S3, introducing deep levels inside the band gap, while Zn and Br/Cl act as shallow acceptors and donors, respectively, for controlling carrier and trap densities. Defect complexes, such as Cu(Zn)(Sb) + V-S and Cl(Br)(S) + V-Sb, have shallower defect levels, which are less detrimental to carrier transport due to interaction between donor and acceptor defects.
PHYSICAL REVIEW MATERIALS
(2021)
Article
Chemistry, Physical
Maya Chaaban, Azza Ben-Akacha, Michael Worku, Sujin Lee, Jennifer Neu, Xinsong Lin, J. S. Raaj Vellore Winfred, Cordell J. Delzer, Jason P. Hayward, Mao-Hua Du, Theo Siegrist, Biwu Ma
Summary: Ionically bonded organic metal halide hybrids exhibit versatile properties due to the vast structural diversity and scaffolding effects of 2D metal halides. The emissions in these materials are attributed to BZQ(+) cations, which show enhanced photoluminescence and stability. Changing the halide from Cl to Br introduces heavy atom effects, leading to yellow room temperature phosphorescence from BZQ(+) cations.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Dan Han, Chunbao Feng, Mao-Hua Du, Tao Zhang, Shizhe Wang, Gang Tang, Thomas Bein, Hubert Ebert
Summary: The emergence of halide double perovskites has opened up new possibilities for lead-free and stable photovoltaic absorbers. However, most halide double perovskites possess large band gaps or transitions that are not ideal for solar cell applications. By designing and screening pnictogen-based quaternary antiperovskites, researchers have identified five stable compounds with promising properties for photovoltaic applications, showing potential for efficiencies exceeding 29%, comparable to or higher than lead-based perovskites.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2021)
Article
Physics, Applied
Xiuli Yang, Sai Mu, Hongliang Shi, Mao-Hua Du
Summary: This study investigates the emission spectra properties of zero-dimensional halide perovskites using computational methods and finds that the emission energies of different self-trapped excitons are consistent with experimental data. The results show that light-induced trapped states can be observed experimentally, confirming the consistency between experimental and calculated results.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Chemistry, Physical
Dan Han, Shiyou Chen, Mao-Hua Du
Summary: Recent studies have shown that two-dimensional hybrid organic-inorganic perovskites (HOIPs) with pi-conjugated molecules as organic moieties exhibit energy and charge transfers between the organic and inorganic layers, suggesting efficient carrier transport for photovoltaic applications. By utilizing density functional theory calculations, researchers have found that the polycyclic aromatic group in n = 1 2D Ruddlesden-Popper phase HOIPs plays a critical role in controlling the functionality of the materials, and the band alignment at the organic-inorganic interface can be tailored to either promote exciton trapping or dissociation for specific applications.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Andrew F. May, Jiaqiang Yan, Raphael Hermann, Mao-Hua Du, Michael A. McGuire
Summary: The effect of increasing the electron count through arsenic substitution on the magnetic properties of Fe5-xGeTe2 has been investigated. Small additions of arsenic enhance ferromagnetic order, while larger concentrations decrease the ferromagnetic Curie temperature and saturation magnetization. This work also discovers a magnetic transition in Fe4.8AsTe2 and emphasizes the importance of controlling the magnetic properties in materials by fine tuning of the Fermi energy or crystal chemistry.
Article
Materials Science, Multidisciplinary
Wei Luo, Mao-Hua Du, Fernando A. Reboredo, Mina Yoon
Summary: In this work, we propose a mechanism to control the magnetic properties of topological quantum materials (TQMs) by utilizing magnetoelectric coupling. This mechanism involves using a heterostructure of TQM with two-dimensional (2D) ferroelectric materials to dynamically control the magnetic order and induce possible topological phase transitions. We demonstrate this concept using the example of bilayer MnBi2Te4 on ferroelectric In2Se3 or In2Te3, where the polarization direction of the 2D ferroelectrics determines the interfacial band alignment and charge transfer direction, resulting in enhanced stability of the ferromagnetic state and possible topological phase transitions between the quantum anomalous Hall effect and the zero plateau quantum anomalous Hall effect.
Article
Materials Science, Multidisciplinary
Shang Gao, Andrew F. May, Mao-Hua Du, Joseph A. M. Paddison, Hasitha Suriya Arachchige, Ganesh Pokharel, Clarina dela Cruz, Qiang Zhang, Georg Ehlers, David S. Parker, David G. Mandrus, Matthew B. Stone, Andrew D. Christianson
Summary: The study reveals that the spin excitations in CuInCr4S8 are hierarchical and can be approximated by an effective model of correlated tetrahedra at low energies, while intratetrahedron excitations and strong magnon-phonon couplings are observed at higher energies, indicating the potential role of lattice degree of freedom in stabilizing the spin tetrahedra. This work demonstrates a general effective-cluster approach to understanding dynamics on breathing-type lattices.
Article
Chemistry, Physical
Tielyr D. Creason, Hadiah Fattal, Isaiah W. Gilley, Timothy M. McWhorter, Mao-Hua Du, Bayram Saparov
Summary: Ternary copper-(I) halides have been explored as alternatives to lead halide perovskites for light emission applications. By substituting silver for copper in high-efficiency blue-emitting Cu-(I) halides, (NH4)2AgBr3 and (NH4)2AgI3 were found to emit broadband whitish light with improved air and moisture stability compared to their copper analogues. The broadband emission in (NH4)2AgX3 is attributed to the presence of high-stability self-trapped excitons and defect-bound excitons.
