Direct synthesis of graphitic mesoporous carbon from green phenolic resins exposed to subsequent UV and IR laser irradiations

Abstract

The design of mesoporous carbon materials with controlled textural and structural features by rapid, cost-effective and eco-friendly means is highly demanded for many fields of applications. We report herein on the fast and tailored synthesis of mesoporous carbon by UV and IR laser assisted irradiations of a solution consisting of green phenolic resins and surfactant agent. By tailoring the UV laser parameters such as energy, pulse repetition rate or exposure time carbon materials with different pore size, architecture and wall thickness were obtained. By increasing irradiation dose, the mesopore size diminishes in the favor of wall thickness while the morphology shifts from worm-like to an ordered hexagonal one. This was related to the intensification of phenolic resin cross-linking which induces the reduction of H-bonding with the template as highlighted by 13C and 1H NMR. In addition, mesoporous carbon with graphitic structure was obtained by IR laser irradiation at room temperature and in very short time periods compared to the classical long thermal treatment at very high temperatures. Therefore, the carbon texture and structure can be tuned only by playing with laser parameters, without extra chemicals, as usually required.

Eco-Friendly Synthesis of Nitrogen-Doped Mesoporous Carbon for Supercapacitor Application

“…Another two peaks are detected at 108 and 40 ppm indicating cross-linked phloroglucinol with glyoxylic acid via covalent bondings. The detailed mechanism of cross-linking was previously reported in our works [30,32,38]. An intense contribution is seen at~72 ppm and a small one at 20 ppm corresponding to the carbons atoms in -CH, -CH 2 and -CH 3 groups present in the PPO (polypropylene oxide) and PEO (polyethylene oxide) moieties of the Pluronic F-127 template.…”

“…Firstly, the glyoxylic acid as a green precursor extracted from plants was proposed for the first time as cross-linker alternative instead of formaldehyde with no requirements of supplementary base/acid catalyst in the synthesis. Such a green synthesis pathway was successfully used to prepare mesoporous carbon powders and films with tuned pore size and geometries, various graphitization levels via classical approaches like EISA and phase separation [30], but also by novel more unconventional routes assisted by light [31,32]. Recently two green approaches have been developed to prepare N-doped porous carbon.…”

Structure-mechanical property relations of non-graphitizing pyrolytic carbon synthesized at low temperatures

“…Such an insight helps dispel the confusion in the literature that surrounds why some PyCs get softer as T p increases, while others remain superhard, and this is directly the result of the evolution of their average L a , L c , and d 002 . Since the three-dimensional shape of the pores enclosed by the crystallites and the crystallite curvature/orientation are important inputs for mechanical modeling, but were not available for this study since they cannot be quantified using traditional electron microscopy approaches that yield two-dimensional projections, further work via electron tomography (for three-dimensional crystallite visualization) [91], small angle X-ray scattering (for large sampled volume quantitative analysis) [92,93], and selected area electron diffraction (for crystallite texture/preferential alignment quantification) [14,44,45] is required and could enable improved mechanical property predictions for PyCs [60]. Comparison of the H V results of PyCs using their apparent density (ρ) and the design parameters for lightweight (H V /ρ) and super lightweight (H 1/2 V /ρ and H 1/3 V /ρ) material design parameters shows that the performance of the PyCs studied here is average for superhard materials using the H V /ρ design parameter, and among the best performing superhard materials when the H 1/2 V /ρ and H 1/3 V /ρ design parameter are used.…”

Hard carbons derived from green phenolic resins for Na-ion batteries

“…13C CP-MAS NMR spectra show several chemical shifts in the range 200-0 ppm with the main resonances rather similar for each sample. The peaks correspond to carbon atoms from different initial precursors species as well as from cross-linked products formed by the polymerization reaction between glyoxylic acid and phloroglucinol in the presence of solvent as identified elsewhere [32,33]. The chemical shift at 176.9 ppm corresponds to the carbon atoms of carboxylic group (C=O) present in glyoxylic acid.…”