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3. Thickness-dependent electronic relaxation dynamics in solution-phase redox-exfoliated MoS2 heterostructures.

Author

Jeffries, William R., Jawaid, Ali M., Vaia, Richard A., and Knappenberger Jr., Kenneth L.

Subjects
*HETEROSTRUCTURES, *MOLYBDENUM disulfide, *EXPONENTIAL functions, *MULTILAYERS, *MONOMOLECULAR films, *SEMICONDUCTOR defects
Abstract

Electronic relaxation dynamics of solution-phase redox-exfoliated molybdenum disulfide (MoS2) monolayer and multilayer ensembles are described. MoS2 was exfoliated using polyoxometalate (POM) reductants. This process yields a colloidal heterostructure consisting of MoS2 2D sheet multilayers with surface-bound POM complexes. Using two-dimensional electronic spectroscopy, transient bleaching and photoinduced absorption signals were detected at excitation/detection energies of 1.82/1.87 and 1.82/1.80 eV, respectively. Approximate 100-fs bandgap renormalization (BGR) and subsequent defect- and phonon-mediated relaxation on the picosecond timescale were resolved for several MoS2 thicknesses spanning from 1 to 2 L to ∼20 L. BGR rates were independent of sample thickness and slightly slower than observations for chemical vapor deposition-grown MoS2 monolayers. However, defect-mediated relaxation accelerated ∼10-fold with increased sample thicknesses. The relaxation rates increased from 0.33 ± 0.05 to 1.2 ± 0.1 and 3.1 ± 0.4 ps−1 for 1–2 L, 3–4 L, and 20 L fractions. The thicknesses-dependent relaxation rates for POM-MoS2 heterostructures were modeled using a saturating exponential function that showed saturation at thirteen MoS2 layers. The results suggest that the increased POM surface coverage leads to larger defect density in the POM-MoS2 heterostructure. These are the first descriptions of the influence of sample thickness on electronic relaxation rates in solution-phase redox-exfoliated POM-MoS2 heterostructures. Outcomes of this work are expected to impact the development of solution-phase exfoliation of 2D metal-chalcogenide heterostructures. [ABSTRACT FROM AUTHOR]

Published
2024
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7. List of contributors

Author

Akimitsu, Nobuyoshi, primary, Alexeeva, Marina, additional, Almeida, Juliana, additional, Ávila-Avilés, Rodolfo Daniel, additional, Berthelier, Jérémy, additional, Bhatnagar, Akanksha, additional, Boskovic, Maria, additional, Carullo, Nancy V.N., additional, Casas-Mollano, J. Armando, additional, Champagne, Frances A., additional, Chen, Taiping, additional, Chhabra, Ravindresh, additional, Curley, James P., additional, Davison, Gareth W., additional, Dunbar, Gary L., additional, Eggermann, Thomas, additional, Elefant, Felice, additional, Fransquet, Peter D., additional, Fujii, Hodaka, additional, Fujita, Toshitsugu, additional, Furci, Leonardo, additional, Garcia, Jose, additional, Ghosh, Balaram, additional, Gillberg, Linn, additional, Giménez-Orenga, Karen, additional, Hanna, Courtney W., additional, Herceg, Zdenko, additional, Hernández-Hernández, J. Manuel, additional, Hjort, Line, additional, Hu, Xiaotong, additional, Ibeagha-Awemu, Eveline M., additional, Jawaid, Ali, additional, Jiang, Wei, additional, Juez, Oscar, additional, Karnay, Ashley M., additional, Kawata, Kentaro, additional, Khatib, Hasan, additional, Klee, Eric W., additional, Klein, Kerstin, additional, Kremer, Eloïse A., additional, Kronholm, Ilkka, additional, Lee, Ho-Sun, additional, Magdinier, Frédérique, additional, Mansuy, Isabelle M., additional, Mashoodh, Rahia, additional, Mezei, Mihaly, additional, Miah, Maria, additional, Miryeganeh, Matin, additional, Mujtaba, Shiraz, additional, Munster, Pamela N., additional, Murr, Rabih, additional, Navakauskienė, Rūta, additional, Negrón-Lomas, Claudia, additional, Nugent, Fereshteh S., additional, Oltra, Elisa, additional, Onoguchi-Mizutani, Rena, additional, Öztürk, Nail Can, additional, Pacaud, Romain, additional, Peedicayil, Jacob, additional, Pethe, Prasad, additional, Pfeifer, Gerd P., additional, Pulya, Sravani, additional, Rauch, Tibor A., additional, Resendiz, Marisol, additional, Roalsø, Marcus, additional, Robin, Jérôme D., additional, Rossignol, Julien, additional, Ryan, Joanne, additional, Santos-Rebouças, Cíntia Barros, additional, Saze, Hidetoshi, additional, Shepard, Ryan D., additional, Silar, Philippe, additional, Sklias, Athena, additional, Slager, Susan L., additional, Søreide, Kjetil, additional, Srinageshwar, Bhairavi, additional, Suter, David M., additional, Taniue, Kenzui, additional, Thomas, Scott, additional, Tian, Shulan, additional, Tollefsbol, Trygve O., additional, van der Giezen, Mark, additional, Vanzan, Ludovica, additional, Vogt, Günter, additional, Watkins, Darryl S., additional, Watson, Martin M., additional, Wei, Loo Keat, additional, Wrigglesworth, Jo, additional, Yamada, Toshimichi, additional, Yan, Huihuang, additional, Yang, Jie, additional, Ying, Zhengzhou, additional, Zacarias, Ericka, additional, and Zhou, Feng C., additional

Published
2023
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18. Right to culture

Author

European MD-PhD Association, Negi, Swati, and Jawaid, Ali

Published
2017

24. Contributors

Author

Anderson, Sean T., primary, Anderson, Olivia S., additional, Balcerczyk, Aneta, additional, Beacon, Tasnim H., additional, Beetch, Megan, additional, Biesiekierska, Marta, additional, Caporossi, Daniela, additional, Chapman, Christopher G., additional, Crew, Rachael C., additional, Davie, James R., additional, Dimauro, Ivan, additional, DiTacchio, Luciano, additional, Evans, Levi, additional, Ferguson, Bradley S., additional, Greenwood-Van Meerveld, Beverley, additional, Gupta, Subash C., additional, Harandi-Zadeh, Sadaf, additional, Ibay, Iara Cassandra V., additional, Isabelli, Allison, additional, Jahan, Sanzida, additional, Jawaid, Ali, additional, Johnson, Anthony C., additional, Lane, Robert H., additional, Lee, Ho-Sun, additional, Li, Jiao, additional, Louwies, Tijs, additional, Majnik, Amber V., additional, Mansuy, Isabelle M., additional, Mark, Peter J., additional, Martinez-Guryn, Kristina, additional, Mihaylova, Maria M., additional, Needham, Belinda L., additional, Odenwald, Matthew A., additional, Orock, Albert, additional, Osman, Fadumo D.S., additional, Paronetto, Maria Paola, additional, Paschos, Georgios K., additional, Peng, Yong, additional, Pirola, Luciano, additional, Poteres, Elesa, additional, Rai, Vipin, additional, Rehkopf, David H., additional, Ribarič, Samo, additional, Romanick, Samantha, additional, Sant, Karilyn E., additional, Segar, Jeffrey L., additional, Sepehri, Zahra, additional, Shen, Kate, additional, Shinmura, Ken, additional, Shukla, Kamla Kant, additional, Stefanska, Barbara, additional, Stratton, Matthew S., additional, van Steenwyk, Gretchen, additional, Verma, Sumit S., additional, Vialichka, Varvara, additional, Waddell, Brendan J., additional, Xu, Xiangru, additional, Yan, Menghong, additional, Yuan, Tian, additional, Zahnow, Cynthia A., additional, Zhou, Tong, additional, and Zhu, Lei, additional

Published
2019
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31. Exfoliation Procedure-Dependent Optical Properties of Solution Deposited MoS2 Films

Author

Stevenson, Peter, primary, Busch, Robert, additional, Sun, Lirong, additional, Austin, Drake, additional, Jiang, Jie, additional, Miesle, Paige, additional, Susner, Michael, additional, Conner, Benjamin, additional, Jawaid, Ali, additional, Becks, Shannon, additional, Mahalingam, Krishnamurthy, additional, Velez, Michael, additional, Torsi, Riccardo, additional, Robinson, Joshua, additional, Rao, Rahul, additional, Glavin, Nicholas, additional, Pachter, Ruth, additional, Vaia, Richard, additional, Kennedy, W, additional, and Vernon, Jonathan, additional

Published
2022
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34. Contributors

Author

Akimitsu, Nobuyoshi, primary, Almeida, Juliana, additional, Au, Anthony, additional, Ayyappan, Vasudevan, additional, Casas-Mollano, J. Armando, additional, Champagne, Frances A., additional, Chen, Taiping, additional, Chhabra, Ravindresh, additional, Chi, Tian, additional, Curley, James P., additional, Dunbar, Gary L., additional, Dworkin, Mollee C., additional, Eggermann, Thomas, additional, Elefant, Felice, additional, Fujii, Hodaka, additional, Fujita, Toshitsugu, additional, Gaonkar, Krutika S., additional, Gay, Steffen, additional, Gillberg, Linn, additional, Hattori, Naoko, additional, Hawkins, Kimberly E., additional, Hayford, Rita K., additional, Herceg, Zdenko, additional, Hjort, Line, additional, Hu, Xiaotong, additional, Ibeagha-Awemu, Eveline M., additional, Jawaid, Ali, additional, Jüngel, Astrid, additional, Kalavacharla, Venu (Kal), additional, Karnay, Ashley M., additional, Keat Wei, Loo, additional, Khatib, Hasan, additional, Klein, Kerstin, additional, Kremer, Eloïse A., additional, Kronholm, Ilkka, additional, Lalucque, Hervé, additional, Lee, Ho-Sun, additional, Li, Yongqin, additional, Liu, Bo, additional, Liu, Shuiping, additional, Lo, Chiao-Ling, additional, Maciejewska-Rodrigues, Hanna, additional, Magdinier, Frédérique, additional, Maiti, Panchanan, additional, Malagnac, Fabienne, additional, Mansuy, Isabelle M., additional, Mao, Shaoshuai, additional, Martinez, J. Alfredo, additional, Mashoodh, Rahia, additional, Milagro, Fermin I., additional, Mizutani, Rena, additional, Mujtaba, Shiraz, additional, Munster, Pamela N., additional, Murr, Rabih, additional, Navakauskienė, Rūta, additional, Nguyen, Tinh-Suong, additional, O’Neill, Chris, additional, Okpala, Ifeanyi, additional, Okpala, Martin-Joseph, additional, Orakwue, Zimuzoh, additional, Park, Jeenah, additional, Peedicayil, Jacob, additional, Pfeifer, Gerd P., additional, Pirrotta, Vincenzo, additional, Rauch, Tibor A., additional, Resendiz, Marisol, additional, Robin, Jérôme D., additional, Rossignol, Julien, additional, Saffery, Richard, additional, Schumacher, Axel, additional, Shifman, Michael I., additional, Silar, Philippe, additional, Sklias, Athena, additional, Slager, Susan L., additional, Søreide, Kjetil, additional, Srinageshwar, Bhairavi, additional, Subramani, Mayavan, additional, Sweatt, J. David, additional, Szyf, Moshe, additional, Terranova-Barberio, Manuela, additional, Thomas, Scott, additional, Tian, Shulan, additional, Tollefsbol, Trygve O., additional, Ushijima, Toshikazu, additional, Vanzan, Ludovica, additional, Veland, Nicolas, additional, Vogt, Günter, additional, Vryer, Regan, additional, Watson, Martin M., additional, Yamada, Toshimichi, additional, Yan, Huihuang, additional, Zacarias, Ericka, additional, Zhong, Allison Y., additional, and Zhou, Feng C., additional

Published
2017
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35. Promoting human rights through science

Author

Sills, Jennifer, Segal, Lauren, Chow, Ryan Dz-Wei, Kumar, Brijesh, Nguyen, Jenny, Yu, Kun-Hsing, Chen, Jennifer, Polat, Emre Ozan, Porter, Kaitlyn Elizabeth, Kelly-Irving, Michelle, Bimpe, Israel, Winter, Kristy A., Zeng, Runxi, Ahmed, Majid, Saalman, Dustin Ray, James, Joshua Isaac, Kosinski, Michal, White, Easton R., Oda, Fernanda S., Bretscher, Hope, Hamel, Perrine, Negi, Swati, and Jawaid, Ali

Published
2017
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36. Redox exfoliated NbS2: characterization, stability, and oxidation.

Author

Nagaoka, Danilo A., Grasseschi, Daniel, Cadore, Alisson R., Fonsaca, Jessica E. S., Jawaid, Ali M., Vaia, Richard A., and de Matos, Christiano J. S.

Abstract

Niobium disulfide is a layered transition metal dichalcogenide that is being exploited as a two-dimensional material. Although it is a superconductor at low temperatures and demonstrates great potential to be applied as a catalyst or co-catalyst in hydrogen evolution reactions, only a few reports have demonstrated the synthesis of a few-layer NbS2. However, before applications can be pursued, it is essential to understand the main characteristics of the obtained material and its stability under an atmospheric environment. In this work, we conducted a thorough characterization of redox-exfoliated NbS2 nanoflakes regarding their structure and stability in an oxygen-rich environment. Structural, morphological, and spectroscopic characterization demonstrated different fingerprints associated with distinct oxidation processes. This led us to identify oxide species and analyse the stability of the redox exfoliated NbS2 nanosheets in air, suggesting the most likely reaction pathways during the NbS2 interaction with oxygen, which agrees with our density-functional theory results. The mastery over the stability of layered materials is of paramount importance to target future applications, mainly because the electronic properties of these materials are strongly affected by an oxidizing environment. [ABSTRACT FROM AUTHOR]

Published
2023
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40. NextGen VOICES

Author

KRINSKY, BENJAMIN H., NGUYEN, NEILSON, ARTHUR, PATRICK KOBINA, JAWAID, ALI, POULSEN, ERIK ESMANN, MARASINI, BISHNU P., MERJONEN, PÄIVI, RIAZ, HARIS, ZHAO, JIANG, LUCIANO, LUIS B. GÓMEZ, SANTOS, GUILHERME MARTINS, WARD, ADRIAN, HASENKOPF, CHRISTA A., and STEVENSON, SETH M.

Published
2013
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41. Second Harmonic Scattering of Redox Exfoliated Two-Dimensional Transition Metal Dichalcogenides

Author

Maldonado, Melissa, Amaral, Anderson, Behel, Zacharie, Salmon, Estelle, de Araújo, Cid, Gomes, Anderson, Jawaid, Ali, Ritter, Allyson, Vaia, Richard, and jonin, christian

Subjects
[PHYS.PHYS.PHYS-OPTICS] Physics [physics]/Physics [physics]/Optics [physics.optics], Two-Dimensional Materials, Second Harmonic Scattering, Femtosecond Regime, Layered Transition Metal Dichalcogenides, [PHYS.COND.CM-MS] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]
Abstract

We report the second harmonic scattering experiments from acetonitrile liquid suspensions of two-dimensional metal dichalcogenide nanoflakes,: the semiconducting MoS2 and WS2, the metallic NbS2, and the semi-metallic ZrTe2. Because the study is directly performed in the liquid phase, no symmetry breaking can be attributed to a supporting substrate as it is often the case in the investigation of the second harmonic generation efficiency for these materials. A comparative look of the origin of the nonlinear response using polarization analysis of the hyper Rayleigh scattering intensity is performed. Retardation is clearly exhibited by all nanoflakes considering their average dimensions but remains weak. This is attributed to the non-negligible role played by the nanoflake edges or the presence of surface absorbed polyoxometalates (POMs), in all cases.

Published
2022

42. Exfoliation procedure-dependent optical properties of solution deposited MoS2 films.

Author

Busch, Robert T., Sun, Lirong, Austin, Drake, Jiang, Jie, Miesle, Paige, Susner, Michael A., Conner, Benjamin S., Jawaid, Ali, Becks, Shannon T., Mahalingam, Krishnamurthy, Velez, Michael A., Torsi, Riccardo, Robinson, Joshua A., Rao, Rahul, Glavin, Nicholas R., Vaia, Richard A., Pachter, Ruth, Joshua Kennedy, W., Vernon, Jonathan P., and Stevenson, Peter R.

Subjects
OPTICAL properties, OPTICAL coatings, CHEMICAL peel, OPTICAL devices, SEMICONDUCTOR films, BANDPASS filters
Abstract

The development of high-precision large-area optical coatings and devices comprising low-dimensional materials hinges on scalable solution-based manufacturability with control over exfoliation procedure-dependent effects. As such, it is critical to understand the influence of technique-induced transition metal dichalcogenide (TMDC) optical properties that impact the design, performance, and integration of advanced optical coatings and devices. Here, we examine the optical properties of semiconducting MoS2 films from the exfoliation formulations of four prominent approaches: solvent-mediated exfoliation, chemical exfoliation with phase reconversion, redox exfoliation, and native redox exfoliation. The resulting MoS2 films exhibit distinct refractive indices (n), extinction coefficients (k), dielectric functions (ε1 and ε2), and absorption coefficients (α). For example, a large index contrast of Δn ≈ 2.3 is observed. These exfoliation procedures and related chemistries produce different exfoliated flake dimensions, chemical impurities, carrier doping, and lattice strain that influence the resulting optical properties. First-principles calculations further confirm the impact of lattice defects and doping characteristics on MoS2 optical properties. Overall, incomplete phase reconfiguration (from 1T to mixed crystalline 2H and amorphous phases), lattice vacancies, intraflake strain, and Mo oxidation largely contribute to the observed differences in the reported MoS2 optical properties. These findings highlight the need for controlled technique-induced effects as well as the opportunity for continued development of, and improvement to, liquid phase exfoliation methodologies. Such chemical and processing-induced effects present compelling routes to engineer exfoliated TMDC optical properties toward the development of next-generation high-performance mirrors, narrow bandpass filters, and wavelength-tailored absorbers. [ABSTRACT FROM AUTHOR]

Published
2023
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44. Ultrasensitive Molecular Sensors Based on Real‐Time Impedance Spectroscopy in Solution‐Processed 2D Materials (Adv. Funct. Mater. 12/2022)

Author

Moore, David C., primary, Jawaid, Ali, additional, Busch, Robert, additional, Brothers, Michael, additional, Miesle, Paige, additional, Miesle, Adam, additional, Rao, Rahul, additional, Lee, Jonghoon, additional, Beagle, Lucas K., additional, Motala, Michael, additional, Wallace, Shay Goff, additional, Downing, Julia R., additional, Roy, Ajit, additional, Muratore, Christopher, additional, Hersam, Mark C., additional, Vaia, Richard, additional, Kim, Steve, additional, and Glavin, Nicholas R., additional

Published
2022
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48. Picosecond Thermal Nonlinearities in 2D – NbS2

Author

Germano, Gleice C. M., primary, da Silva Neto, Manoel L., additional, Maldonado, Melissa, additional, Camara, Alexandre R., additional, Araújo, Leonardo F., additional, Jawaid, Ali M., additional, Vaia, Richard A, additional, Moura, André L., additional, Gomes, Anderson S. L., additional, and Carvalho, Isabel C. S., additional

Published
2022
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50. Ultrasensitive Molecular Sensors Based on Real‐Time Impedance Spectroscopy in Solution‐Processed 2D Materials

Author

Moore, David C., primary, Jawaid, Ali, additional, Busch, Robert, additional, Brothers, Michael, additional, Miesle, Paige, additional, Miesle, Adam, additional, Rao, Rahul, additional, Lee, Jonghoon, additional, Beagle, Lucas K., additional, Motala, Michael, additional, Wallace, Shay Goff, additional, Downing, Julia R., additional, Roy, Ajit, additional, Muratore, Christopher, additional, Hersam, Mark C., additional, Vaia, Richard, additional, Kim, Steve, additional, and Glavin, Nicholas R., additional

Published
2021
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