Layered Materials

• 2D materials act as excellent substrates and templates for single atom catalysts. Providing well-defined adsorption sites, they judiciously utilize precious, catalytically active metals, giving rise to families of photo- and electro- catalysts. 

S. Agrawal, D. Casanova, D. J. Trivedi, O. V. Prezhdo, “Enhanced Charge Separation in Single Atom Cobalt Based Graphitic Carbon Nitride: Time Domain Ab Initio Analysis”, J. Phys. Chem. Lett., 15, 2202-2208 (2024).

X. Cao, D. W. Zhang, Y. Q. Gao, O. V. Prezhdo, L. Xu, “Design of Boron and Transition Metal Embedded Two-Dimensional Porous Carbon Nitride for Electrocatalytic Synthesis of Urea”, J. Am. Chem. Soc., 146, 1042-1052 (2023).

D. Zhang, O. V. Prezhdo, L. Xu, “Design of a Four-Atom Cluster Embedded in Carbon Nitride for Electrocatalytic Generation of Multi-Carbon Products”, J. Am. Chem. Soc., 145, 7030-7039 (2023).

• Relative angle between layers can give rise to interesting Moire patterns. At certain twist angles, few layer films exhibit unusual properties, such as flat electron bands and superconductivity, creating a potential for the “twistronics” technology. Excited state dynamics in twisted bilayers show interesting angle dependence as well.

Y. H. Zhu, O. V. Prezhdo, R. Long, W. H. Fang, “Twist Angle-Dependent Intervalley Charge Carrier Transfer and Recombination in Bilayer WS2”, J. Am. Chem. Soc., 145 22826-22835 (2023).

Y. H. Zhu, W. H. Fang, A. Rubio, R. Long, O. V. Prezhdo, “The Twist Angle Has Weak Influence on Charge Separation and Strong Influence on Recombination in the MoS2/WS2 Bilayer: Ab Initio Quantum Dynamics”, J. Mater. Chem. A, 10, 8324-8333 (2022).

• Strong confinement of charges within layers enhances charge-charge scattering, making it competitive with electron-vibrational relaxation. As the charge excitation density increases, the system becomes more metallic, and the Coulomb interactions get screened, leading to a transition from excitons to excitonic strings, to charge droplets, and to plasma regime. These phenomena create an intriguing interplay between different pathways in the excited state dynamics.

L. Q. Li, M. F. Lin, X. Zhang, A. Britz, A. Krishnamoorthy, R. R. Ma, R. K. Kalia, A. Nakano, P. Vashishta, P. Ajayan, M. C. Hoffmann, D. M. Fritz, U. Bergmann, O. V. Prezhdo, “Phonon-Suppressed Auger Scattering of Charge Carriers in Defective Two-Dimensional Transition Metal Dichalcogenides”, Nano Lett., 19, 6078-6086 (2019).

Z. G. Nie, R. Long, L. F. Sun, C. C. Huang, J. Zhang, Q. H. Xiong, D. W. Hewak, Z. X. Shen, O. V. Prezhdo, Z. H. Loh, “Ultrafast carrier thermalization and cooling dynamics in few-layer MoS2”, ACS Nano, 8, 10931-10940 (2014).

• As all nanoscale materials, layered materials are not perfect, and contain point defects, wrinkles, junctions, etc. These imperfections complicate interpretations of experiments, strongly motivating our simulations.

C. Xu, N. Barden, E. M. Alexeev, X. L. Wang, R. Long, A. R. Cadore, I. Paradisanos, A. K. Ott, G. Soavi, S. Tongay, G. Cerullo, A. C. Ferrari, O. V. Prezhdo, Z. H. Loh, “Ultrafast Charge Transfer and Recombination Dynamics in Monolayer-Multilayer WSe2 Junctions Revealed by Time-Resolved Photoemission Electron Microscopy”, ACS Nano, 18, 1931-1947 (2023).

C. Xu, G. Q. Zhou, E. M. Alexeev, A. R. Cadore, I. Paradisanos, A. K. Ott, G. Soavi, S. Tongay, G. Cerullo, A. C. Ferrari, O. V. Prezhdo, Z. H. Loh, “Ultrafast Electronic Relaxation Dynamics of Atomically Thin MoS2 Is Accelerated by Wrinkling”, ACS Nano, 17, 16682-16694 (2023).

L. Q. Li, R. Long, O. V. Prezhdo, “Why chemical vapor deposition grown MoS2 samples outperform physical vapor deposition samples: time-domain ab initio analysis”, Nano Lett., 18, 4008-4014 (2018).