Effective Surface Areas and Adsorption Capacity of Graphene with Vacancies

Title from PDF of title page, viewed September 5, 2023Dissertation advisor: Da-Ming ZhuVitaIncludes bibliographical references (pages 78-97)Dissertation (Ph.D.)--Department of Physics and Astronomy, Department of Computer Science and Electrical Engineering. University of Missouri--Kansas City, 2023Graphene has been heavily researched since Geim and Novosolov won the nobel prize in physics for its mechanical exfoliation from graphite. The atomically thin crystal of carbon atoms has been reported to have novel properties across varied metrics. One such metric is the incredibly high specific surface area of 2360²⁻¹. Literature has advised the employment of graphene with vacancy defects for applications such as sensors, separation, supercapacitors, and batteries. Pores have been put into devices for these applications, yet the effects of vacancies in graphene require more study to be fully understood. An alarming discrepancy exists between the theoretical and experimental determination of graphene’s specific surface area. It is proposed here that experimental samples may contain vacancy defects, leading to an overestimation of specific surface area. Presented here is both an analytical discussion and a molecular dynamics based approach of evaluating the effects of pore size and pore geometry on potential energy, adsorption capacity calculation and effective specific surface area. It is determined that a single vacancy defect can lead to an increase (~300 m² g⁻¹) in specific surface area as well as adsorption capacity. 73% of this increase is shown to be due to an increase in adsorption in a conical volume around the introduced pore.Introduction -- Background information -- Fabrication, applications and challenges of nanoporous graphene -- Thesis and preliminary results -- Analytical discussion -- Overview of molecular dynamics experiment -- Conclusions and future wor

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