Publications by authors named "Douglas D Vargas"

To prevent eutrophication, controlling the phosphate concentration levels is one of the most important issues in surface water management. One of the most utilized methods is phosphate adsorption. However, its application faces a bottleneck due to the unclear understanding of adsorption and interaction mechanisms.

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Modeling water and other liquids in computational simulations requires a large set of parameters. Many works have been devoted to finding new, improved water models, with almost all of them designed for bulk systems. Here, we use carbon nanotubes as a play model to investigate the effects of introducing flexibility in water force fields during molecular dynamics simulations of nanoconfined water.

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First-principles calculations within DFT have been performed to investigate the use of a recently synthesized form of silicene, the dumbbell (DB) silicene as an anode material for Li-ion batteries (LiBs). The energetically most stable geometries for Li adsorption on DB silicene were investigated, and the energy barriers for Li-ion diffusion among the possible stable adsorption sites were calculated. We found that DB silicene can be lithiated up to a ratio of 1.

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Contact electrification (triboelectrification) has been a long-standing phenomenon for 2600 years. The scientific understanding of contact electrification (triboelectrification) remains un-unified as the term itself implies complex phenomena involving mechanical contact/sliding of two materials involving many physico-chemical processes. Recent experimental evidence suggests that electron transfer occurs in contact electrification between solids and liquids besides the traditional belief of ion adsorption.

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Single layers of hexagonal boron nitride (h-BN) and silicene are brought together to form h-BN/silicene van der Waals (vdW) heterostructures. The effects of external electric fields and compressive strain on their structural and electronic properties are systematically studied through first principles calculations. Two silicene phases are considered: the low-buckled Si(LB) and the dumbbell-like Si(DB).

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