Article
Chemistry, Physical
Shilin Zhang, Tian Lu, Pengcheng Xu, Qiuling Tao, Minjie Li, Wencong Lu
Summary: By combining machine learning with the SHAP approach, a strategy was proposed to accelerate the discovery of potential HOIPs, revealing key guidelines for the formability of materials in the HOIP structure.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Inorganic & Nuclear
Yu-Hsuan Su, Wei-Liang Chen, Hye Ryung Byun, Yu-Fu Zhang, Min-Rui Zhuang, Yu-Cih Lin, Chung-Kai Chang, Po-Yuan Wang, Che-Cheng Lin, Kuang- Lin, Hsin-Kuan Liu, Min-Kai Lee, Joon Jang, Yu-Ming Chang, Kuei-Fang Hsu
Summary: A new copper indium selenide with an orthorhombic crystal structure was synthesized at 800 degrees C. It emits intense photoluminescence at 657 nm and exhibits a direct band gap with an energy close to the photoluminescence position. The compound also shows n-type conductivity and strong nonlinear third-harmonic generation.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Physical
Marco A. Ruiz-Preciado, Fabrizio Gota, Paul Fassl, Ihteaz M. Hossain, Roja Singh, Felix Laufer, Fabian Schackmar, Thomas Feeney, Ahmed Farag, Isabel Allegro, Hang Hu, Saba Gharibzadeh, Bahram Abdollahi Nejand, Veronique S. Gevaerts, Marcel Simor, Pieter J. Bolt, Ulrich W. Paetzold
Summary: This study successfully fabricated high-efficiency perovskite/CIS tandem solar cells, showcasing the potential of monolithic two-terminal structure. By optimizing the techniques, a power conversion efficiency approaching 25% was achieved, setting the foundation for future improvements in efficiency.
ACS ENERGY LETTERS
(2022)
Article
Chemistry, Physical
P. Priyadarshini, S. Senapati, Sagar Bisoyi, S. Samal, R. Naik
Summary: In this study, CuInSe2 (CIS) nanosheets with different Zn doping content were synthesized using a simple hot injection method. The introduction of Zn led to the amorphous nature inside the CIS matrix and structural rearrangements in the system. The Zn doping also enhanced optical absorption and decreased the optical band gap, making the material suitable for solar cell applications. The observed broad absorbance and photoluminescence emission, as well as improved dielectric properties, suggest the potential of CIS for various optoelectronics and photonics devices.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Multidisciplinary Sciences
Xiaoming Zhao, Melissa L. Ball, Arvin Kakekhani, Tianran Liu, Andrew M. Rappe, Yueh-Lin Loo
Summary: Understanding structure-property relationships is crucial for designing functional materials. In this study, the authors propose a descriptor to predict the electronic properties of two-dimensional lead iodide perovskites for photovoltaic applications. By introducing bifunctional ligands, the material properties and device characteristics of perovskite solar cells can be improved.
NATURE COMMUNICATIONS
(2022)
Article
Engineering, Civil
Linyun Zhou, Wenwen Han, Shui Wan
Summary: This article investigates the band gap structure of elastic metamaterials, focusing on the design challenges of lightweight and low frequency band gaps. The use of inerter-based dynamic vibration absorbers is proposed to achieve low frequency band gaps.
THIN-WALLED STRUCTURES
(2022)
Article
Acoustics
Jinqiang Li, Yu Xue, Fengming Li
Summary: An innovative special class of magnetorheological metamaterial is proposed in this study to achieve a tunable band gap by using a new frequency feedback control law. The active control function of the band gap is realized using an intelligent local resonator embedded in the plate. The results show that the damping of the MRE plays an important role in the control of the band gap of the magnetorheological metamaterial.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Nanoscience & Nanotechnology
A. Kochaev, M. Maslov, K. Katin, V. Efimov, I. Efimova
Summary: Unilateral surface passivation by hydrogen atoms is an effective method to stabilize borophene-graphene with periodic perforation. Without hydrogen, a transition from porous graphene to graphenylene is observed. In the H-passivated porous borophene-graphene, covalent and van der Waals forces act between boron and carbon layers. Ab initio calculations confirm the stability through cohesive energy and phonon spectrum. The electronic properties show semiconductor nature mainly due to boron sites. The elasticity response is weaker than borophene-graphene, but the out-of-plane piezoelectric effect is stronger. Optical properties, especially absorption peak values in the optical range, are of particular interest.
MATERIALS TODAY NANO
(2022)
Article
Materials Science, Multidisciplinary
Zhiyu Yang, Yifei Zhao, Jumpei Ueda, Maxim S. Molokeev, Mengmeng Shang, Zhiguo Xia
Summary: In this study, a blue-light-excitable red-emitting phosphor Ce3+-doped SrLaScO4 (SLO:Ce3+) was discovered. Spectroscopy and structural analyses confirmed that Ce3+ ions competitively occupied the [LaO8] polyhedrons, generating a strong crystal field splitting and a large Stokes shift, resulting in a red emission. Furthermore, incorporating a large electronegative Ga3+ in the Sc3+ site effectively enhanced the thermal stability of SLO:Ce3+ by suppressing the thermally stimulated ionization process, thereby presenting a general design principle for discovering novel Ce3+-doped red phosphors with good thermal stability for white light-emitting diode (WLED) applications.
SCIENCE CHINA-MATERIALS
(2023)
Article
Chemistry, Inorganic & Nuclear
Nethmi W. Hewage, Gayatri Viswanathan, Philip Yox, Kui Wu, Kirill Kovnir, Georgiy Akopov
Summary: Non-centrosymmetric semiconductors have significant nonlinear optical properties, and a careful balance of SHG, LDT, and phase-matchability is required for practical applications. This study developed a synthetic method to produce solid solution and high-entropy sulfides containing up to 9 elements, and explored their crystal structure and NLO properties. The findings demonstrate the potential of these materials for enhanced SHG and improved LDT compared to standard materials.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Inorganic & Nuclear
Nethmi W. Hewage, Gayatri Viswanathan, Philip Yox, Kui Wu, Kirill Kovnir, Georgiy Akopov
Summary: Non-centrosymmetric semiconductors exhibit important nonlinear optical properties. We developed a method to synthesize solid solutions and high-entropy sulfides, and studied their crystal structure and optical properties. The results show that most of these materials have good phase matchability, with the high-entropy alloy containing Cu showing higher SHG signal enhancement and LDT value.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Physical
Matthew B. Gray, Jackson D. Majher, Noah P. Holzapfel, Patrick M. Woodward
Summary: The study investigates the structural and optical properties of halide substitutions of Br- and I- into (Cs4MM2Cl12)-M-II-Cl-III, showing that significant bromide incorporation is possible, while iodide incorporation is more limited. The larger halide ions can result in a red shift of the onset of optical absorption, providing insights into stabilizing the vacancy-ordered quadruple perovskite structure.
CHEMISTRY OF MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
Rongjian Sa, Qiqi Zhang, Yuqing Yang, Diwen Liu
Summary: In this study, a theoretical approach was used to investigate the electronic and optical properties of alloyed Na1-xAgxSbS2 compounds. The results showed that NaSbS2 has good stability when the Ag doping concentration is 50%, and alloying can improve its photovoltaic efficiency.
MATERIALS RESEARCH BULLETIN
(2022)
Article
Multidisciplinary Sciences
Karukh A. Babakr, Omid Amiri, L. Jay Guo, Mohammad Ali Rashi, Peshawa H. Mahmood
Summary: Mechanical energy harvesting using piezoelectric materials for catalysis reactions shows great potential for environmental remediation. In this study, SbSI/Sb2S3 nanocomposites were synthesized as a catalyst and ZrO2 balls were used as an alternative mechanical force to ultrasonic vibration. The effects of different mechanical forces, the number of ZrO2 balls, and reaction temperature on the degradation efficiency were investigated. The use of ZrO2 balls resulted in a 47% enhancement in degradation efficiency compared to ultrasonic vibration at 30 +/- 5 degrees C.
SCIENTIFIC REPORTS
(2022)
Article
Materials Science, Ceramics
Zhenya Wang, Hao Guo, De Ning, Xiaobai Ma, Lirong Zheng, Dmitry Smirnov, Kai Sun, Dongfeng Chen, Limei Sun, Xiangfeng Liu
Summary: The article presents a synergistic strategy of tuning localized electrons in Li4Ti5O12 through Mg/Zr co-doping and oxygen vacancy incorporation to improve its conductivity. The study reveals that co-doping and vacancy incorporation effectively enhance the dynamic characteristics of the LTO electrode, achieving excellent rate performance and cycle stability.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2021)
Review
Physics, Multidisciplinary
S. Siebentritt, T. P. Weiss
Summary: Chalcopyrite solar cells play a crucial role in mitigating the climate crisis due to their low carbon emissions. Improvements in efficiency have been achieved through post-deposition treatments with heavy alkalis. However, limitations in open circuit voltage are caused by tail states and band gap distribution. Increased diode factor hampers further efficiency improvements due to metastable defect transitions. Alloying with Ag shows potential for band-edge engineering and diode factor enhancement. Passivation of the back contact in state-of-the-art cells has been extensively researched. Tandem cells are expected to significantly improve efficiency. Chalcopyrite solar cells show promising potential as both bottom and top cells.
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY
(2023)
Editorial Material
Energy & Fuels
Susan Schorr
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2023)
Article
Materials Science, Multidisciplinary
Pedro Borlido, Friedhelm Bechstedt, Silvana Botti, Claudia Roedl
Summary: Ge-rich hexagonal SiGe alloys have emerged as new direct-gap semiconductors with potential for integration of photonics on silicon. Optical, transport, and thermoelectric properties of these alloys were investigated using first-principles methods. The alloy band gap remains direct below 45% Si content and optical spectra show tunability with composition. Transport coefficients exhibit similar behaviors in cubic and hexagonal alloys, but the latter display anisotropic response due to reduced symmetry. The Seffbeck coefficients and thermoelectric power factors show nonmonotonous variations with Si content regardless of temperature.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Energy & Fuels
Santhanu Panikar Ramanandan, Andrea Giunto, Elias Z. Stutz, Benoit Reynier, Ileane Tiphaine Francoise Marie Lefevre, Marin Rusu, Susan Schorr, Thomas Unold, Anna Morral, Jose A. Marquez, Mirjana Dimitrievska
Summary: This work explores the synthesis of BaZrS3 from Ba-Zr-O oxide precursor films sulfurized at temperatures ranging from 700 degrees C to 1000 degrees C. The diffusion of sulfur species in the film is identified as the rate-limiting step of this reaction. The processing temperature plays a significant role in determining the conversion from oxide to sulfide phase. BaZrS3 demonstrates a unique ability to accommodate non-stoichiometric compositions, unlike other chalcogenides.
JOURNAL OF PHYSICS-ENERGY
(2023)
Article
Chemistry, Multidisciplinary
Christian Kameni Boumenou, Himanshu Phirke, Jonathan Rommelfangen, Jean-Nicolas Audinot, Shiro Nishiwaki, Tom Wirtz, Romain Carron, Alex Redinger
Summary: Alkali post deposition treatments (PDTs) have been used to improve the power conversion efficiency (PCE) of Cu(In,Ga)Se-2 solar cell devices. However, a detailed understanding of how PDTs impact the nanoscale optoelectronic properties is still lacking. In this study, various scanning probe techniques and spectroscopy methods were used to show that RbF PDT treatments result in an exchange of Rb with Cu at the surface. The existence of the RbInSe2 phase is unlikely to be responsible for the recent improvements in PCE.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Jonathan Schmidt, Noah Hoffmann, Hai-Chen Wang, Pedro Borlido, Pedro J. M. A. Carrico, Tiago F. T. Cerqueira, Silvana Botti, Miguel A. L. Marques
Summary: Crystal-graph attention neural networks are powerful tools for predicting thermodynamic stability. By using a high-quality dataset, these networks show exceptional generalization accuracy and are used for high-throughput searches to discover compounds with unique properties.
ADVANCED MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Evgeny Krueger, Michael Seifert, Volker Gottschalch, Harald Krautscheid, Claudia S. Schnohr, Silvana Botti, Marius Grundmann, Chris Sturm
Summary: We studied the excitonic transition energy E-0 and spin-orbit split-off energy Delta(0) of gamma-AgxCu1-xI alloy thin films using reflectivity measurements at temperatures between 20 K and 290 K. The observed bowing behavior of the E-0 transition as a function of alloy composition is explained based on first-principles band structure calculations. The spin-orbit coupling increases with increasing Ag-content, and the temperature-dependent bandgap shift decreases with increasing Ag-content.
Article
Multidisciplinary Sciences
Giancarlo Cappellini, Juergen Furthmueller, Friedhelm Bechstedt, Silvana Botti
Summary: We conducted a systematic investigation on the electronic and optical properties of two crystals of alkaline earth metal fluorides using state-of-the-art techniques. The calculations were performed using density functional theory, many-body perturbation theory, and the Bethe-Salpeter equation. Our results showed distinctive properties for rutile MgF2 compared to cubic SrF2 and other members of the alkaline earth metal fluoride family. The excitonic effects in finite-sized systems were confirmed through a comparison between bulk and cluster calculations.
Article
Physics, Applied
Thomas Paul Weiss, Omar Ramirez, Stefan Paetel, Wolfram Witte, Jiro Nishinaga, Thomas Feurer, Susanne Siebentritt
Summary: Cu(In,Ga)Se2-based solar cells achieve power conversion efficiencies exceeding 23%. However, the fill factor of these cells is relatively low due to diode factors greater than 1, mainly caused by metastable defects in the Cu(In,Ga)Se2 alloy. Excitation-dependent photoluminescence measurements reveal that the increased diode factor can be well explained by the model of metastable defects. Optically measured diode factors impose a lower limit on the electrical diode factor of finished solar cells. Ag alloying provides a pathway to increase fill factors and efficiencies for Cu(In,Ga)Se2-based solar cells.
PHYSICAL REVIEW APPLIED
(2023)
Article
Energy & Fuels
Omar Ramirez, Jiro Nishinaga, Felix Dingwell, Taowen Wang, Aubin Prot, Max Hilaire Wolter, Vibha Ranjan, Susanne Siebentritt
Summary: The detrimental effect of tail states on V-OC in Cu(In,Ga)Se-2 solar cells has been shown. Alkali metals can reduce tail states by passivating charged defects at grain boundaries. This study investigates the effect of compositional variations and alkali incorporation on tail states in Cu(In,Ga)Se-2 films. The results reveal that sodium and potassium can decrease the density of tail states, even in the absence of grain boundaries, suggesting additional mechanisms beyond grain boundaries for the alkali effects. Moreover, doping-induced increase in sodium or potassium incorporation contributes to the reduced tail states, which are primarily caused by electrostatic potential fluctuations and influenced by grain interior properties. By analyzing the voltage loss in high-efficiency polycrystalline and single crystalline devices, this work presents a comprehensive model explaining the voltage loss in Cu(In,Ga)Se-2 based on the combined effect of doping on tail states and V-OC.
Article
Chemistry, Physical
Konrad Ritter, Galina Gurieva, Stefanie Eckner, Rene Schwiddessen, Francesco d'Acapito, Edmund Welter, Susan Schorr, Claudia S. Schnohr
Summary: This study investigates the local atomic structure of off-stoichiometric kesterite materials and analyzes the influence of off-stoichiometry on bond stretching force constants, average bond lengths, and variances. The findings provide insight into the possible local configurations and their impact on the electronic properties and application of kesterites in solar cells.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Nanoscience & Nanotechnology
Aubin JC. M. Prot, Michele Melchiorre, Felix Dingwell, Anastasia Zelenina, Hossam Elanzeery, Alberto Lomuscio, Thomas Dalibor, Maxim Guc, Robert Fonoll-Rubio, Victor Izquierdo-Roca, Gunnar Kusch, Rachel A. Oliver, Susanne Siebentritt
Summary: The article discusses the achievement of record efficiency in chalcopyrite-based solar cells using a gallium gradient and reveals non-radiative recombination issues at the back contacts of industrial absorbers. The study proposes a model where discrete bandgap phases interlace to form an apparent gradient throughout the thickness of the absorber.
Article
Materials Science, Multidisciplinary
Tomas Rauch, Pavel Marton, Silvana Botti, Jiri Hlinka
Summary: Photocatalytic water splitting is a promising strategy for large-scale clean energy production, but efficient and low-cost solid-state photocatalysts are still lacking. In this study, first-principles calculations were used to investigate the suitability of an epitaxial layer of strontium germanate on a Si(100) single crystal as a photocathode. The conduction and valence band offsets at the interface between these two semiconductors were determined using state-of-the-art approximations of density functional theory. The resulting band lineup was confirmed by inspection of the spatially resolved density of states. It was concluded that the conduction band offset of the investigated heterostructure is favorable for photocathodic functionality.
Correction
Materials Science, Multidisciplinary
Abderrezak Belabbes, Silvana Botti, Friedhelm Bechstedt
Article
Materials Science, Multidisciplinary
Abderrezak Belabbes, Silvana Botti, Friedhelm Bechstedt
Summary: This study investigates the natural and true band profiles at heterojunctions formed by hexagonal SixGe1-x alloys. The findings show that the natural band offsets are not significantly affected by different alignment methods or functional choices. Ge-rich alloys exhibit a type-I heterocharacter with direct band gaps, while Si-rich junctions are type-I but with an indirect band gap. The true band lineups at pseudomorphically grown heterostructures are strongly influenced by the biaxial strain generated in the adjacent alloys.
