Aluminum is well-known for its particularly high resistance to corrosion through oxidation and this is attributed to the formation of a thin oxide film on the surface of the material. This protective layer acts as a barrier to diffusion, preventing further deterioration. However, the mechanisms causing slow diffusion through oxide films are poorly understood, limiting development of highly resistant materials, especially for high-temperature environments. As a foundation for further computational research on diffusivity of defects and defect clusters, we use density functional theory to calculate formation energies of point defects in aluminum oxide from first-principles. We confirm previous studies showing that a peroxide split interstitial defect is energetically favorable to the traditionally considered, quasi-atomic oxygen interstitial defect at the octahedral site. We also find displaced ground-state configurations for aluminum interstitials, investigate the viability of octahedral configurations for extrinsic interstitials, and examine the impact of defect charge state on the ground-state geometry. The overlooked lower-energy geometries could influence defect migration paths and change predictions for diffusion properties in metal oxides. Materials capable of withstanding continual ion radiation are highly desirable in space and nuclear applications. A detailed understanding of the mechanisms leading to degradation of materials under ion bombardment would enable targeted development of radiation resistant materials. As an energetic charged particle penetrates a material's surface, it deposits energy and excites electrons, leading to secondary electron (SE) emission and localized charge within the material. Even when direct collisions with nuclei are rare, fs scale surface charge dynamics may cause Coulomb explosion, which would damage and erode the material surface. We use time-dependent density functional theory to characterize SE emission, surface charge dynamics, and atomic forces in few-layer aluminum sheets under proton-irradiation. From first-principles, we compute exit-side and entrance-side SE yields, SE energy spectra, and time scales of charge equilibration within the material as the projectile velocity and material thickness are varied. We also estimate the momentum acquired by aluminum atoms near the impact point. These simulations provide unprecedented insight into the dynamical response of materials' surfaces to ion bombardment. Ion-irradiation of materials enables techniques like ion beam microscopy and can lead to material degradation in space and nuclear technology. Thin or two-dimensional materials respond to ion-irradiation differently than their bulk counterparts, and characterizing this pre-equilibrium response is essential for developing applications. We use Ehrenfest dynamics to simulate a 25 keV proton traversing a 0.8-1.6 nm thick aluminum sheet at a proton dose of 2.4*10^13 cm^-2. We analyze the time-dependent electron density to obtain the entrance-side and exit-side secondary electron yields and the orbital occupations of the exiting projectile. From our results for position-dependent stopping in the target, we also compute the effective charge of the projectile inside the target. Finally, we consider the dependence of these quantities on target thickness. Our approach overcomes challenges posed by artificial interaction between entrance-side and exit-side secondary electron densities and integration error accumulated after propagating Kohn-Sham orbitals for thousands of time steps in large simulation volumes. Two-dimensional materials including graphene are promising candidates for optoelectronic devices because of their unique properties and the ability to fabricate layered heterostructures. However, the properties of these materials are often sensitive to nanostructure, requiring high-resolution imaging and patterning techniques, which typically employ focused ion beams. Achieving higher precision control of the structure and properties of two-dimensional materials like graphene necessitates a detailed understanding of the excited electron dynamics occurring in the material in response to ion irradiation. Using real-time time-dependent density functional theory, we simulate 0.5-4.6 au H+, He2+, Si4+, and Xe8+ ions traversing monolayer and trilayer graphene. We obtain the energy transfer and the charge induced in the material from a combination of charge transfer and electron emission. We also examine the excited charge dynamics in the material, and we investigate the dependence of these quantities on projectile velocity, trajectory, species, and charge as well as graphene thickness.