Article
Spectroscopy
E. B. Chubenko, N. L. Grevtsov, V. P. Bondarenko, I. M. Gavrilin, A. V. Pavlikov, A. A. Dronov, L. S. Volkova, S. A. Gavrilov
Summary: This study investigates the regularities of composition changes in silicon/germanium alloy thin films formed by electrochemical deposition of germanium into a porous silicon matrix on a single-crystalline silicon substrate, followed by rapid thermal annealing (RTA) at temperatures ranging from 750 to 950 degrees Celsius. Raman spectroscopy analysis reveals that increasing the RTA temperature results in a decrease in the germanium concentration in the formed film. Moreover, reducing the RTA duration at a given temperature allows for the production of films with higher germanium concentration and the ability to control the composition of the thin silicon/germanium alloy films by adjusting the RTA temperature and duration.
JOURNAL OF APPLIED SPECTROSCOPY
(2022)
Article
Physics, Multidisciplinary
Xin Gan, Junyang An, Junzhuan Wang, Zongguang Liu, Jun Xu, Yi Shi, Kunji Chen, Linwei Yu
Summary: In this study, a self-oscillating growth phenomenon of catalyst droplets was utilized to achieve high-frequency alternating growth of ultrathin crystalline Si and Ge nano-slates. A subsequent selective etching process generated ultrafine standing c-Si nanosheets. This method doesn't require expensive lithography and growth control.
CHINESE PHYSICS LETTERS
(2023)
Article
Crystallography
Gopal Singh Attar, Mimi Liu, Cheng-Yu Lai, Daniela R. Radu
Summary: This study successfully synthesized Ge-Sn alloy nanoparticles with different Sn compositions and achieved long-term stability through surface passivation and removal of the oxide layer using (NH4)2S, providing potential for future use of these Ge1-xSnx nanoalloys in optoelectronic devices.
Article
Optics
Halil Can Nalbant, Fatih Balli, Tolga Yelboga, Arda Eren, Ahmet Sozak
Summary: This work presents the design and fabrication of high transmission metalenses operating at the long-wave infrared spectrum. By employing an anti-reflection coating, the reflection losses are minimized while maintaining full wavefront control at the central wavelength. Experimental results demonstrate diffraction-limited imaging of the fabricated metalenses at the design wavelength.
Article
Materials Science, Multidisciplinary
Elnaz Bahmani, Ali Zakeri, Alireza Sabour Rouh Aghdam
Summary: The study investigates the electrodeposition of silver-germanium alloy coatings, finding that 6% germanium content is optimal for dense and uniform microstructure as well as the best corrosion resistance. Formation of the Ag-Ge biphasic alloy results in a shift in lattice parameter of silver. The surface morphology of the coating transforms from nodular to cauliflower-like with increasing germanium content, and the corrosion current density of the Ag-6Ge alloy is approximately 20 times lower than Ag-0.5Ge and 6 times lower than pure silver.
JOURNAL OF MATERIALS SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Anna A. Lizunova, Vladislav I. Borisov, Dana Malo, Andrey G. Musaev, Ekaterina I. Kameneva, Alexey A. Efimov, Ivan A. Volkov, Arseny I. Buchnev, Ivan A. Shuklov, Victor V. Ivanov
Summary: The modified spark discharge method was used to synthesize Ge/Sn nanoparticles consisting of independent germanium and tin crystals. The atomic fraction of tin to germanium ranged from 0.08 to 0.24. The research investigated the elemental and phase composition, size, morphology, and spectroscopic properties of the synthesized nanoparticles.
Article
Chemistry, Multidisciplinary
Wonill Ha, Sieu D. Ha, Maxwell D. Choi, Yan Tang, Adele E. Schmitz, Mark P. Levendorf, Kangmu Lee, James M. Chappell, Tower S. Adams, Daniel R. Hulbert, Edwin Acuna, Ramsey S. Noah, Justine W. Matten, Michael P. Jura, Jeffrey A. Wright, Matthew T. Rakher, Matthew G. Borselli
Summary: Spin-based silicon quantum dots are an attractive qubit technology for quantum information processing, and we present an exchange-only Si qubit platform named SLEDGE that combines high throughput wafer processing with versatile direct-write lithography. The SLEDGE technology features dot-shaped gates and interconnect metal lines, allowing for flexible layout design and various gate dimensions, material selections, and additional device features.
Article
Engineering, Electrical & Electronic
Michael Oehme, Mathias Kaschel, Steffen Epple, Maurice Wanitzek, Zili Yu, Daniel Schwarz, Ann-Christin Kollner, Joachim N. Burghartz, Jorg Schulze
Summary: This paper presents a near-infrared Ge-on-Si camera with backside illumination, showcasing high fill-factor and linear photocurrent characteristics. By operating the Ge-on-Si detectors under zero bias, dark current is minimized and high signal-to-noise ratio and optical responsivity are achieved.
IEEE SENSORS JOURNAL
(2021)
Article
Optics
Ziv Glasser, Pawan Kumar Dubey, Ayuushi Dutta, Egor Liokumovitch, Rita Abramov, Shmuel Sternklar
Summary: The optoelectronic process in photodiodes is a significant source of optoelectronic chromatic dispersion (OED). Simple design rules have been developed for fabricating photodiode-based dispersion devices with different OED. Silicon-based devices are predicted to exhibit significant OED in the near IR, while Ge and InGaAs have high OED in specific bands.
Article
Materials Science, Multidisciplinary
Marian Rynik, Stefano Leoni, Roman Martonak
Summary: The pressure-induced structural transformation of Ge-136 clathrate was studied using ab initio molecular dynamics and metadynamics. The system undergoes amorphization followed by a rapid recrystallization to the beta-tin structure. The amorphous intermediate remains diffusive even at room temperature, allowing for the ultrafast recrystallization.
Article
Chemistry, Physical
Donglin Huang, Ruoyun Ji, Liqiang Yao, Jinlong Jiao, Xiaoqiang Chen, Cheng Li, Wei Huang, Songyan Chen, Shaoying Ke
Summary: This study reports the nucleation of dislocations in Ge/Si bonded pairs annealed at low temperatures (≤400 degrees C), revealing two types of dislocation networks near the bonded interface. Thermal stress is identified as the main driving force for dislocation nucleation, with the annealing temperature impacting the type and distribution of dislocations. A kinetic model is constructed to explain the strain relaxation process and dislocation behavior, showing that heterogeneous nucleation dominates at low annealing temperatures while a multiplication mechanism becomes active at elevated temperatures.
APPLIED SURFACE SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Nicolas Forrer, Arianna Nigro, Gerard Gadea, Ilaria Zardo
Summary: Nanowires have attracted significant attention as building blocks for functional devices at the nanoscale. In this study, the growth kinetics of silicon and germanium nanowires synthesized by chemical vapor deposition using a vapour-liquid-solid growth method catalyzed by gold were examined. The effects of temperature, partial pressure of the precursor gas, and different carrier gases on the growth rate were analyzed. Optimal conditions for nucleation in the nanowire growth process were identified.
Article
Chemistry, Multidisciplinary
Crispin R. W. Reinhold, Marc Schmidtmann, Boris Tumanskii, Thomas Mueller
Summary: The synthesis of persistent sila- and germacyclopentadienyl radicals by stoichiometric reduction of corresponding halides with potassium is reported in this study. The radicals were characterized by EPR spectroscopy and trapping reactions. Comparing the molecular structures of closely related potassium silolides provided an example for different coordination of the potassium cation to the silolyl anion that triggers the switch between delocalized and localized states.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Kathryn A. Newton, Heather Renee Sully, Frank Bridges, Sue A. Carter, Susan M. Kauzlarich
Summary: Microwave-assisted heating methods were utilized to synthesize oleylamine-capped Ge1-xSnx nanocrystals with varying Sn compositions. The effects of synthesis temperature on the particle size, composition, and structure of the nanocrystals were demonstrated through different experimental techniques, including Raman spectroscopy, X-ray diffraction, and NMR. The study also involved ligand exchange experiments and characterization of the surface ligands before and after the exchange process.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Nanoscience & Nanotechnology
Oluwatobi Olorunsola, Solomon Ojo, Grey Abernathy, Yiyin Zhou, Sylvester Amoah, P. C. Grant, Wei Dou, Joe Margetis, John Tolle, Andrian Kuchuk, Wei Du, Baohua Li, Yong-Hang Zhang, Shui-Qing Yu
Summary: A SiGeSn/GeSn/SiGeSn single quantum well structure was prepared and characterized in this work. The GeSn well layer of the sample was thicker, reaching 22nm, compared to the previously reported 9nm well configuration. This thicker well layer resulted in three improvements: (i) a lowered ground energy level in the Gamma valley, providing more bandgap directness; (ii) an increased carrier density in the well; and (iii) improved carrier collection due to increased barrier height. Consequently, significantly enhanced emission from the quantum well was observed. The strong photoluminescence signal allowed for the estimation of quantum efficiency (QE), which was unattainable in previous studies. Using pumping-power-dependent photoluminescence spectra at 20K, the peak spontaneous QE and external QE were measured as 37.9% and 1.45%, respectively.
Article
Engineering, Environmental
Shuo Liu, Mihir Shah, Satyarit Rao, Lu An, Mohammad Moein Mohammadi, Abhishek Kumar, Shenqiang Ren, Mark T. Swihart
Summary: This study presents a scalable and potentially low-cost method for producing hollow nanostructured materials using a High Temperature Reducing Jet flame aerosol reactor. Hollow nanoshells were successfully synthesized from aqueous salt solutions without the need for templates or surfactants. The incorporation of hollow alumina into thermal insulation was shown to reduce thermal conductivity by 30% relative to pure fiberglass, while maintaining fire resistance and elasticity.
CHEMICAL ENGINEERING JOURNAL
(2022)
Review
Engineering, Environmental
Bhavana Joshi, Edmund Samuel, Yong-il Kim, Alexander L. Yarin, Mark T. Swihart, Sam S. Yoon
Summary: Carbon nanofibers derived from electrospun precursors show great promise for electronic applications by integrating metal oxides and sulfides, eliminating various problems, and offering a cost-effective strategy for fabrication of lightweight lithium-ion batteries with high capacity.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Materials Science, Multidisciplinary
Meifeng Wang, Yiru Qin, Wei Shao, ZhiWang Cai, Xiaoyu Zhao, Yongjun Hu, Tao Zhang, Sheng Li, Mark T. Swihart, Yang Liu, Wei Wei
Summary: Surface modification of NaREF4 UCNPs with different functional molecules can enhance their multiple functionalities. A strategy based on heterovalent cation exchange reaction significantly increases the density of surface RE3 + ions, leading to improved loading capacity and enhanced colloidal stability and photodynamic therapy efficacy of the nanoparticles.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Physics, Multidisciplinary
Yuri S. Djikaev, Eli Ruckenstein, Mark Swihart
Summary: This study examines the validity of using the Fokker-Planck equation as an approximation to the kinetic equation of nucleation in multicomponent condensation. By analyzing the smallness of parameters, it is found that deviations from the Fokker-Planck equation can occur under certain conditions. Numerical calculations suggest that modifications to the conventional kinetic equation may be necessary for consistent comparison with experimental data.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2022)
Article
Engineering, Environmental
Shuo Liu, Chaochao Dun, Jilun Wei, Lu An, Shenqiang Ren, Jeffrey J. Urban, Mark T. Swihart
Summary: Hollow-structured materials, such as hollow silica nanoshells, have shown promise in thermal insulation due to their ability to interrupt heat transport pathways. In this study, two low-cost methods, gas-phase and liquid-phase synthesis routes, were used to fabricate hollow silica nanoshells. Both methods resulted in amorphous hollow silica with low thermal conductivity, small particle size, thin shell, and low density. Furthermore, hollow silica-fiberglass composite ceramics were successfully fabricated using high shear mechanical mixing, providing robust mechanical elasticity and fire-retardancy while maintaining low thermal conductivity.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Biomedical
Shahad Bakheet Alsharif, Rofida Wali, Stephen T. Vanyo, Sebastiano Andreana, Kaiwen Chen, Bhoomika Sheth, Mark T. Swihart, Rosemary Dziak, Michelle B. Visser
Summary: This study examined a novel strontium-loaded alginate scaffold device, which promotes fibroblast migration and repair by releasing strontium ions, aiming to improve peri-implant mucosal healing and clinical success following implant placement.
JOURNAL OF BIOMEDICAL MATERIALS RESEARCH PART A
(2023)
Article
Nanoscience & Nanotechnology
Abhishek Kumar, Kaiwen Chen, Thomas Thundat, Mark T. Swihart
Summary: This paper presents a paper-based sensor using ultrathin palladium nanowires for room-temperature hydrogen detection. The polycrystalline PdNWs showed a response of 4.3% and the quasi-single-crystalline PdNWs showed a response of 8% to 1 vol% H2. The sensor demonstrates excellent selectivity, stability, and sensitivity, and has the potential to be a low-cost alternative to current H2-sensing solutions.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Liang Qiao, Zheng Fu, Wenxia Zhao, Yan Cui, Xin Xing, Yin Xie, Ji Li, Guanhui Gao, Zhengxi Xuan, Yang Liu, Chaeeon Lee, Yimo Han, Yingwen Cheng, Shengbao He, Matthew R. R. Jones, Mark T. T. Swihart
Summary: Branching phenomena in solution-phase synthesis of Nickel-Based nano-Composites (NBCs) were investigated, and 24 morphologies of NBCs were synthesized through systematic adjustment of multiple synthesis parameters. The relationship between synthesis parameters and resultant morphologies was analyzed, and the formation mechanism of branched NBCs was studied comprehensively. Guidelines for rational solution-phase syntheses of branched nanomaterials were extracted and validated.
Article
Chemistry, Multidisciplinary
Imtej Singh Saggu, Sukhwinder Singh, Kaiwen Chen, Zhengxi Xuan, Mark T. Swihart, Sandeep Sharma
Summary: High performance with lower power consumption is a crucial feature for sensing devices. Tin disulfide (SnS2) nanosheets have emerged as a promising NO2 sensor, but their poor conductivity hinders their applications. To address this, a low-cost ultrasensitive NO2 gas sensor with SnS2/multiwalled carbon nanotube (SnS2/MWCNT) nanocomposites was developed. The nanocomposites exhibited improved conductivity and the sensor displayed high sensitivity and fast recovery rates.
Article
Chemistry, Multidisciplinary
Phillip M. Maffettone, Stuart Campbell, Marcus D. Hanwell, Stuart Wilkins, Daniel Olds
Summary: The accelerated development of modern materials discovery platforms is inseparable from low-cost automation and computation, making the development of artificial intelligence/machine learning more convenient, and increasing the ability to represent complex materials in digital form. In order to better discover new energy materials, AI-driven experiments need to cooperate with researchers and various measurement forms. The potential of using an internet of things approach to achieve self-driving enterprise beamlines can fully utilize light sources, effectively collaborate with other remote materials acceleration platforms, and help stride towards the world's energy future.
CELL REPORTS PHYSICAL SCIENCE
(2022)
Review
Engineering, Environmental
Bhavana Joshi, Edmund Samuel, Yong-Il Kim, Hae-Seok Lee, Mark T. Swihart, Sam S. Yoon
Summary: Developing high-performance energy storage and conversion devices using nanoporous metal-organic framework materials has great potential for renewable and sustainable energy technologies. The restructuring of these materials can enhance specific lithium uptake capacities and rate capabilities for lithium-ion-battery electrodes. This review comprehensively analyzes advanced metal-organic framework composites for electric vehicle-compatible lithium-ion batteries, focusing on achieving rapid charging and long-term cycling performance under high-current-loading conditions. The challenges, future prospects, and research directions for design and synthesis of these composites are also discussed.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Nanoscience & Nanotechnology
Mohammad Malekzadeh, Vishvajeet V. Mane, Zhengxi Xuan, Tymish Y. Ohulchanskyy, Mark T. Swihart
Summary: Laser pyrolysis is used to rapidly heat precursors and induce decomposition and particle nucleation. By utilizing SF6, NaYF4 nanocrystals can be synthesized in a safe and efficient manner. This process shows potential for creating lanthanide-doped fluoride nanomaterials for various applications.
ACS APPLIED NANO MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Sukhwinder Singh, Imtej Singh Saggu, Sukhjinder Singh, Nitish Kumar, Kaiwen Chen, Zhengxi Xuan, Ritu Gupta, Mark T. T. Swihart, Sandeep Sharma
Summary: This study presents a chemiresistive sensor based on a MoS2/SWCNTs composite for the dual detection of DMF and NH3 at room temperature. The composite sensor showed good selectivity and response capabilities, along with environmental stability and increased surface area. These results provide a platform for developing next-generation gas sensors for diverse potential gas-sensing applications.
ACS APPLIED NANO MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Srikanth Ponnada, Demudu Babu Gorle, Indu Kumari, Sakkarapalayam Murugesan Senthil Kumar, Mark T. Swihart, Gerardine G. Botte, Rakesh K. Sharma
Summary: Ammonia is a fundamental chemical feedstock for synthetic fertilizer production, and electrochemical ammonia synthesis is an attractive alternative. Single-atom catalysts, as a new class of catalysts, have many advantages and have been extensively investigated in the field of ammonia synthesis. However, there are still several key challenges to be addressed for these catalysts to achieve commercial success.
MATERIALS CHEMISTRY FRONTIERS
(2023)
Article
Materials Science, Multidisciplinary
Chonghang Zhao, Cheng-Chu Chung, Siying Jiang, Marcus M. Noack, Jiun-Han Chen, Kedar Manandhar, Joshua Lynch, Hui Zhong, Wei Zhu, Phillip Maffettone, Daniel Olds, Masafumi Fukuto, Ichiro Takeuchi, Sanjit Ghose, Thomas Caswell, Kevin G. Yager, Yu-chen Karen Chen-Wiegart
Summary: Machine learning-augmented materials design is a promising approach for rapidly developing new materials, especially for complex nanoarchitectured materials. This study introduces a machine learning approach to explore metal-agent dealloying and predicts 132 possible ternary dealloying systems. The results demonstrate the potential of utilizing machine learning-augmented methods for creating nanoarchitectured thin films.
COMMUNICATIONS MATERIALS
(2022)