Celeste Melamed
Postdoctoral Scholar, Materials Science and Engineering
Bio
Celeste Melamed is a postdoctoral scholar with the Chueh group at Stanford. Her interests include ionics, structural chemistry and transport, and materials by design, with the overarching goal of a sustainable energy economy. She is currently developing thin film synthetic methods to investigate interfacial structure and evolution in solid-state battery materials. She received her PhD in Materials Science at Colorado School of Mines and the National Renewable Energy Laboratory in 2021, where she investigated the interplay between local and long-range structure in new ternary nitrides for optoelectronic applications. She received a B.S. in Physics from Harvey Mudd College in 2015.
Professional Education
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Doctor of Philosophy, Colorado School of Mines (2021)
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PhD, Colorado School of Mines, Materials Science (2021)
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BS, Harvey Mudd College, Physics (2015)
All Publications
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Effect of H<SUP>+</SUP> Exchange and Surface Impurities on Bulk and Interfacial Electrochemistry of Garnet Solid Electrolytes
CHEMISTRY OF MATERIALS
2024; 36 (14): 6849-6864
View details for DOI 10.1021/acs.chemmater.4c00738
View details for Web of Science ID 001279971400001
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Combinatorial Synthesis of Cation-Disordered Manganese Tin Nitride MnSnN2 Thin Films with Magnetic and Semiconducting Properties
CHEMISTRY OF MATERIALS
2023
View details for DOI 10.1021/acs.chemmater.2c03826
View details for Web of Science ID 000960432300001
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Mechanical regulation of lithium intrusion probability in garnet solid electrolytes
NATURE ENERGY
2023
View details for DOI 10.1038/s41560-022-01186-4
View details for Web of Science ID 000921785600002
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Short-Range Order Tunes Optical Properties in Long-Range Disordered ZnSnN2-ZnO Alloy
CHEMISTRY OF MATERIALS
2022; 34 (9): 3910-3919
View details for DOI 10.1021/acs.chemmater.1c03938
View details for Web of Science ID 000801201200004
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Surface conversion of single-crystal Bi2Se3 to beta-In2Se3
JOURNAL OF CRYSTAL GROWTH
2021; 573
View details for DOI 10.1016/j.jcrysgro.2021.126306
View details for Web of Science ID 000702855600001
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Ternary Nitride Materials: Fundamentals and Emerging Device Applications
ANNUAL REVIEW OF MATERIALS RESEARCH, VOL 51, 2021
2021; 51: 591-618
View details for DOI 10.1146/annurev-matsci-080819-012444
View details for Web of Science ID 000684015200023
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Combinatorial investigation of structural and optical properties of cation-disordered ZnGeN2
JOURNAL OF MATERIALS CHEMISTRY C
2020; 8 (26): 8736-8746
View details for DOI 10.1039/d0tc01675f
View details for Web of Science ID 000548739700034
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Utilizing Site Disorder in the Development of New Energy-Relevant Semiconductors
ACS ENERGY LETTERS
2020; 5 (6): 2027-2041
View details for DOI 10.1021/acsenergylett.0c00576
View details for Web of Science ID 000541766000038
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Combinatorial Synthesis of Magnesium Tin Nitride Semiconductors
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
2020; 142 (18): 8421-8430
Abstract
Nitride materials feature strong chemical bonding character that leads to unique crystal structures, but many ternary nitride chemical spaces remain experimentally unexplored. The search for previously undiscovered ternary nitrides is also an opportunity to explore unique materials properties, such as transitions between cation-ordered and -disordered structures, as well as to identify candidate materials for optoelectronic applications. Here, we present a comprehensive experimental study of MgSnN2, an emerging II-IV-N2 compound, for the first time mapping phase composition and crystal structure, and examining its optoelectronic properties computationally and experimentally. We demonstrate combinatorial cosputtering of cation-disordered, wurtzite-type MgSnN2 across a range of cation compositions and temperatures, as well as the unexpected formation of a secondary, rocksalt-type phase of MgSnN2 at Mg-rich compositions and low temperatures. A computational structure search shows that the rocksalt-type phase is substantially metastable (>70 meV/atom) compared to the wurtzite-type ground state. Spectroscopic ellipsometry reveals optical absorption onsets around 2 eV, consistent with band gap tuning via cation disorder. Finally, we demonstrate epitaxial growth of a mixed wurtzite-rocksalt MgSnN2 on GaN, highlighting an opportunity for polymorphic control via epitaxy. Collectively, these findings lay the groundwork for further exploration of MgSnN2 as a model ternary nitride, with controlled polymorphism, and for device applications, enabled by control of optoelectronic properties via cation ordering.
View details for DOI 10.1021/jacs.0c02092
View details for Web of Science ID 000535173500042
View details for PubMedID 32279492
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Using resonant energy X-ray diffraction to extract chemical order parameters in ternary semiconductors
JOURNAL OF MATERIALS CHEMISTRY C
2020; 8 (13): 4350–56
View details for DOI 10.1039/c9tc06699c
View details for Web of Science ID 000526890100036
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Growth of GaAs on single-crystal layered-2D Bi2Se3
JOURNAL OF CRYSTAL GROWTH
2020; 534
View details for DOI 10.1016/j.jcrysgro.2019.125457
View details for Web of Science ID 000513818500010
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Heteroepitaxial Integration of ZnGeN2 on GaN Buffers Using Molecular Beam Epitaxy
CRYSTAL GROWTH & DESIGN
2020; 20 (3): 1868-1875
View details for DOI 10.1021/acs.cgd.9b01578
View details for Web of Science ID 000518701900055
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Combinatorial Tuning of Structural and Optoelectronic Properties in CuXZn1-XS
MATTER
2019; 1 (4): 862-880
View details for DOI 10.1016/j.matt.2019.06019
View details for Web of Science ID 000519847300012
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Ternary nitride semiconductors in the rocksalt crystal structure
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2019; 116 (30): 14829-14834
Abstract
Inorganic nitrides with wurtzite crystal structures are well-known semiconductors used in optical and electronic devices. In contrast, rocksalt-structured nitrides are known for their superconducting and refractory properties. Breaking this dichotomy, here we report ternary nitride semiconductors with rocksalt crystal structures, remarkable electronic properties, and the general chemical formula Mgx TM 1-xN (TM = Ti, Zr, Hf, Nb). Our experiments show that these materials form over a broad metal composition range, and that Mg-rich compositions are nondegenerate semiconductors with visible-range optical absorption onsets (1.8 to 2.1 eV) and up to 100 cm2 V-1⋅s-1 electron mobility for MgZrN2 grown on MgO substrates. Complementary ab initio calculations reveal that these materials have disorder-tunable optical absorption, large dielectric constants, and electronic bandgaps that are relatively insensitive to disorder. These ternary Mgx TM 1-xN semiconductors are also structurally compatible both with binary TMN superconductors and main-group nitride semiconductors along certain crystallographic orientations. Overall, these results highlight Mgx TM 1-xN as a class of materials combining the semiconducting properties of main-group wurtzite nitrides and rocksalt structure of superconducting transition-metal nitrides.
View details for DOI 10.1073/pnas.1904926116
View details for Web of Science ID 000476715500015
View details for PubMedID 31270238
View details for PubMedCentralID PMC6660719
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COMBIgor: Data-Analysis Package for Combinatorial Materials Science
ACS COMBINATORIAL SCIENCE
2019; 21 (7): 537-547
Abstract
Combinatorial experiments involve synthesis of sample libraries with lateral composition gradients requiring spatially resolved characterization of structure and properties. Because of the maturation of combinatorial methods and their successful application in many fields, the modern combinatorial laboratory produces diverse and complex data sets requiring advanced analysis and visualization techniques. In order to utilize these large data sets to uncover new knowledge, the combinatorial scientist must engage in data science. For data science tasks, most laboratories adopt common-purpose data management and visualization software. However, processing and cross-correlating data from various measurement tools is no small task for such generic programs. Here we describe COMBIgor, a purpose-built open-source software package written in the commercial Igor Pro environment and designed to offer a systematic approach to loading, storing, processing, and visualizing combinatorial data. It includes (1) methods for loading and storing data sets from combinatorial libraries, (2) routines for streamlined data processing, and (3) data-analysis and -visualization features to construct figures. Most importantly, COMBIgor is designed to be easily customized by a laboratory, group, or individual in order to integrate additional instruments and data-processing algorithms. Utilizing the capabilities of COMBIgor can significantly reduce the burden of data management on the combinatorial scientist.
View details for DOI 10.1021/acscombsci.9b00077
View details for Web of Science ID 000474812000005
View details for PubMedID 31121098
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Blue-green emission from epitaxial yet cation-disordered ZnGeN2-xOx
PHYSICAL REVIEW MATERIALS
2019; 3 (5)
View details for DOI 10.1103/PhysRevMaterials.3.051602
View details for Web of Science ID 000468238100001
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Exciton photoluminescence and benign defect complex formation in zinc tin nitride
MATERIALS HORIZONS
2018; 5 (5)
View details for DOI 10.1039/c8mh00415c
View details for Web of Science ID 000444245600004
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Band Edge Positions and Their Impact on the Simulated Device Performance of ZnSnN2-Based Solar Cells
IEEE JOURNAL OF PHOTOVOLTAICS
2018; 8 (1): 110-117
View details for DOI 10.1109/JPHOTOV.2017.2766522
View details for Web of Science ID 000418770300016
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Large Area Atomically Flat Surfaces via Exfoliation of Bulk Bi2Se3 Single Crystals
CHEMISTRY OF MATERIALS
2017; 29 (19): 8472-8477
View details for DOI 10.1021/acs.chemmater.7b03198
View details for Web of Science ID 000412965800048
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Combinatorial insights into doping control and transport properties of zinc tin nitride
JOURNAL OF MATERIALS CHEMISTRY C
2015; 3 (42): 11017-11028
View details for DOI 10.1039/c5tc02663f
View details for Web of Science ID 000363663100010