Senftle, Thomas P2022-09-232023-05-012022-052022-04-21May 2022Bhati, Manav. "Multiscale Modeling of Electrochemical Interfaces." (2022) Diss., Rice University. <a href="https://hdl.handle.net/1911/113329">https://hdl.handle.net/1911/113329</a>.https://hdl.handle.net/1911/113329Interfaces are one of the most complicated yet significant junctions in materials where several sciences are at play simultaneously. Modeling such interfaces using computer simulations helps to decipher the interplay of these sciences at an atomic scale, which is difficult with experimental characterizations. Multiscale modeling techniques (described in Chapter 1) and the insights derived by implementing them are of high utility to both experimental and computational researchers. This work utilizes multiscale modeling approaches for a thorough investigation of several crucial interfaces that appear in a range of electrochemical applications. In Chapters 2 and 3, silicon/binder anodes in Li-ion batteries are studied using ReaxFF force field based molecular dynamics simulations. The strategies to develop the best binders for silicon anodes are established by a systematic investigation of several crucial binder properties. In Chapter 4, we developed an electronic grand-canonical formalism with density functional theory to model photo-catalytic reactions occurring at the semiconductor/electrolyte interfaces under constant potential. This is implemented on two reactions systems (hydrogen evolution on SiC and contaminant degradation on BN) to gain insights into key steps of each reaction mechanism on photo-catalytic surfaces. In Chapter 6, time-dependent density functional theory is utilized to investigate the nature of electronic excitations in less-explored yet experimentally-significant non-stoichiometric quantum dots that are ligated and solvated. The charge transfer phenomenon, which is usually absent in the stoichiometric quantum dots, seems to play a major role in influencing the optoelectronic properties of these non-stoichiometric quantum dots. Overall, this work presents several novel findings to assist a better design of electrochemical interfaces: establishes structure-property relationships to engineer best Si/binder interfaces for Li-ion batteries, develops modeling strategies for investigating photo-electrochemical reactions on semiconductor/electrolyte interfaces, and reveals charge transfer phenomenon in non-stoichiometric quantum dots and its impact on their optoelectronic properties.application/pdfengCopyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.BatteriesInterfacesElectrochemistryPhotocatalysisQuantum DotsReaxFFDFTMultiscale modelingSi anodesBindersSiCHERThesis2022-09-23