Amphoteric dissolution of two-dimensional polytriazine imide carbon nitrides in water.
Philos Trans A Math Phys Eng Sci
; 381(2259): 20220339, 2023 Oct 30.
Article
in En
| MEDLINE
| ID: mdl-37691463
ABSTRACT
Crystalline two-dimensional carbon nitrides with polytriazine imide (PTI) structure are shown to act amphoterically, buffering both HCl and NaOH aqueous solutions, resulting in charged PTI layers that dissolve spontaneously in their aqueous media, particularly for the alkaline solutions. This provides a low energy, green route to their scalable solution processing. Protonation in acid is shown to occur at pyridinic nitrogens, stabilized by adjacent triazines, whereas deprotonation in base occurs primarily at basal plane NH bridges, although NH2 edge deprotonation is competitive. We conclude that mildly acidic or basic pHs are necessary to provide sufficient net charge on the nanosheets to promote dissolution, while avoiding high ion concentrations which screen the repulsion of like-charged PTI sheets in solution. This article is part of the theme issue 'Exploring the length scales, timescales and chemistry of challenging materials (Part 2)'.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Philos Trans A Math Phys Eng Sci
Journal subject:
BIOFISICA
/
ENGENHARIA BIOMEDICA
Year:
2023
Document type:
Article
Affiliation country:
United kingdom