Exploring Self-Assembly of 2D Materials: Insights from Graphene Auto-Kirigami Li Yuan

Format:

Book

Thesis/Dissertation

Author/Creator:

Yuan, Li, author.

Contributor:

University of Pennsylvania. Mechanical Engineering and Applied Mechanics., degree granting institution.

Language:

English

Subjects (All):

0537.

0794.

Local Subjects:

0537.

0794.

Physical Description:

1 electronic resource (259 pages)

Contained In:

Dissertations Abstracts International 87-07B

Place of Publication:

Ann Arbor : ProQuest Dissertations and Theses, 2025

Language Note:

English

Summary:

In nature, thin sheets bend, fold, and curve to create functional three-dimensional forms-from insect wings to leaves and flower petals. Over the past decades, such behavior has inspired engineered systems ranging from soft robotics to deployable electronics. Extending these ideas to atomically thin two-dimensional (2D) materials such as graphene opens new opportunities: these materials can transform into structures that extend beyond flat geometry through self-driven processes. Graphene, for example, can spontaneously assemble into self-stacked structures through self-folding, self-tearing, and nearly frictionless self-propagation, all driven by interfacial energy. We introduce the term auto-kirigami (AK) to describe these self-folded and self-propagating structures, in analogy to kirigami-the cutting and folding of thin sheets to create complex morphologies, highlighting the spontaneous nature of this process.AK represents a unique form of self-assembly in 2D materials with implications spanning function, fabrication, and fundamental understanding. Yet, key questions remain regarding how AK initiates and grows, and how it varies across material systems. In particular, the mechanisms that control its onset, directionality, and resulting morphology remain unresolved. To bridge these gaps, we investigate the formation of AK through a comprehensive approach integrating experiments, continuum modeling, and atomistic simulations. Experimentally, I established a reliable method to reproducibly induce AK in graphene using atomic force microscopy, enabling identification of the essential features that define AK. Building on these observations, I developed an anisotropic continuum framework that connects lattice-level anisotropy-arising from fracture toughness, adhesion, and interfacial friction-to the directional growth and shape asymmetry of AK. At the atomistic scale, I conducted molecular dynamics simulations that revealed initiation pathways inaccessible to experiments, showing how graphene's self-adhesion drives the transition from a flat sheet to stable self-folded structures. Overall, this work establishes a unified, atomistically informed understanding of AK formation and elucidates general principles that link mechanics, geometry, and lattice symmetry in self-assembly of 2D materials. This offers new opportunities for programmable structures and functional material design, where controlled morphology is essential

Notes:

Advisors: Carpick, Robert W. Committee members: Turtuliano, Ottman A.; Turner, Kevin T.; Martini, Ashlie; Carpick, Robert

Includes supplementary digital materials

Source: Dissertations Abstracts International, Volume: 87-07, Section: B.

Ph.D. University of Pennsylvania 2025

Vendor supplied data

Local Notes:

School code: 0175

ISBN:

9798276007267

Access Restriction:

Restricted for use by site license