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arXiv · 2211.10208

Acidity of graphene oxide aqueous solutions: the role of hydroxyls unveiled

Yulia V. Novakovskaya
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Abstract

Nonempirical modeling of hydrated single-layer graphene oxide (GO) fragments revealed that at least one, but substantial origin of the acidity of aqueous GO solutions is the dissociation in closely grouped and favorably H-bonded hydroxyls. The process can further be promoted by the adjacent $\pi$-conjugated carbon segments at the edges of GO flakes or their inner defects. The apparent $pK_a$ values of the groups fall in a range of ca. 2.0 to 5.3. Under certain conditions the ionization may become spontaneous.

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Yulia V. Novakovskaya. 2022-11-18. Acidity of graphene oxide aqueous solutions: the role of hydroxyls unveiled. https://arxiv.org/abs/2211.10208

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