1 research outputs found
Facile Soft-Templated Synthesis of High-Surface Area and Highly Porous Carbon Nitrides
Mesoporous
carbon nitride is synthesized in a one-pot approach
using different nonionic surfactants (Pluronic F-127, Pluronic P-123,
and Triton X-100) and a melamine cyanurate hydrogen-bonded complex
using just water as the solvent. We obtain three-dimensional assembled
nanostructures from low-dimensional carbon nitride sheets by taking
advantage of supramolecular assembly of melamine and cyanuric acid,
moderate interactions between the surfactant and precursors, structure
directing effects of the surfactants, and the good thermal stability
of the melamine cyanurate sheets formed around the micelles. Different
morphologies, including sheetlike, hollow spherical, and tubular or
highly porous networks, result depending upon the synthesis approach
and the surfactant/precursor ratio. Pseudoternary phase diagrams map
the composition of the starting solution to the resultant carbon nitride
morphology. Increasing the amount of surfactant leads to a higher
carbon residue (C/N ∼ 1) and large BET surface areas (≤300
m<sup>2</sup>/g). Further tuning of the synthesis parameters as well
as addition of HCl produces uniformly porous nanostructures with a
high porosity (up to 0.8 cm<sup>3</sup>/g), a high surface area (>200
m<sup>2</sup>/g), and yet a stoichiometric C/N ratio (∼0.75).
The synthesized high-surface area carbon nitrides show improved light
absorption and enhanced photocatalytic activity in a rhodamine B dye
degradation reaction under visible light irradiation compared to those
of bulk melamine-derived carbon nitride