Surface modified activated carbon with β-cyclodextrin--Part I. Synthesis and characterization

Area of Science:

• Materials Science
• Surface Chemistry
• Analytical Chemistry

Background:

• Activated carbon (AC) is a versatile material with a high surface area.
• Surface functional groups significantly influence AC properties and applications.
• Understanding and controlling these groups is crucial for material design.

Purpose of the Study:

• To characterize and compare surface functional groups on unmodified, oxidized, reduced, and grafted activated carbon materials.
• To investigate the impact of different surface modification methods on AC properties.
• To analyze the surface area and pore volume characteristics of modified AC.

Main Methods:

• Surface modification via oxidation, reduction, and grafting reactions.
• Characterization using Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS), Scanning Electron Microscopy (SEM), Raman spectroscopy, thermogravimetry analysis (TGA), and Matrix Assisted Laser Desorption Ionization Time of Flight (MALDI-TOF) mass spectrometry.
• Quantification of acidic and basic functional groups using Boehm titration and analysis of surface area/pore volume via nitrogen porosimetry.

Main Results:

• Various functional groups (carboxylic acid, lactone, quinine, phenol, nitro, alcohol, amine, imine, hemi-acetal) were successfully introduced onto AC surfaces.
• Surface modification altered the chemical properties and surface characteristics of AC.
• Nitrogen porosimetry revealed surface area ranging from 95-1350 m²/g and pore volume from 0-0.31 cm³/g for the different AC materials.

Conclusions:

• The study provides a comprehensive characterization of surface-modified activated carbons.
• Different chemical treatments lead to distinct surface functional group profiles and alter AC properties.
• The findings are valuable for tailoring activated carbon materials for specific applications through controlled surface functionalization.