Oriented Attachment Crystal Growth Dynamics of Anisotropic One-dimensional Metal/Metal Oxide Nanostructures: Mechanism, Evidence, and Challenges

Abstract

One-dimensional (1D) inorganic metal/metal oxide nanostructures are of significant interest due to their distinctive physical and chemical properties that are beneficial for various applications. A fundamental understanding of the guiding principles that control the anisotropy and the size of the nanostructures is essential toward developing the building blocks for the fabrication of leading-edge miniaturized devices. Oriented attachment (OA) crystal growth mechanism has been recognized as an effective mechanism for producing 1D anisotropic nanostructures. However, a limited understanding of the OA mechanism could impede the controlled fabrication of 1D nanostructures. This chapter provides a comprehensive summary on recent advances of the OA mechanism and the current state of the art on various in-situ, ex-situ, and theoretical investigations of OA-based crystal growth dynamics as well as the shape and size-controlled kinetics. Other competing crystal growth mechanisms, including seed-mediated growth and Ostwald ripening (OR), are also described. Further, we thoroughly discuss the knowledge gap in current OA kinetic models and the necessity of new kinetic models to elucidate the elongation growth of anisotropic nanostructures. Finally, we provide the current limitations, challenges for the understanding of crystal growth dynamics, and future perspectives to amplify the contributions for the controlled self-assembled 1D nanostructures. This chapter will lay the foundation toward designing novel complex anisotropic materials for future smart devices.