2021 journal article

Effect of surface modification by nitrogen-containing chemicals on morphology and surface characteristics of N-doped pine bark biochars


By: N. Kasera n, S. Hall n & P. Kolar n

author keywords: Biochars; Nitrogen doping; Adsorbents; Waste management; Melamine
UN Sustainable Development Goal Categories
2. Zero Hunger (Web of Science)
13. Climate Action (Web of Science)
Source: Web Of Science
Added: October 4, 2021

In this study, pine bark-derived biochar was modified with melamine, urea, ammonium chloride, and ammonium nitrate to synthesize nitrogen-doped biochars. The effect of chemical modification on the extent of N-doping and surface properties were investigated. The elemental analysis suggested that melamine modified biochar samples had 4.75% nitrogen, higher than nitrogen in other modified biochars. The surface morphology and surface profile were studied with scanning electron microscopy and confocal laser scanning microscopy. X-ray photoelectron spectra showed that N-doped samples' surface nitrogen content increased to 8.3%, 3.9%, 2.3%, and 2.9% for melamine, ammonium chloride, ammonium nitrate, and urea, respectively. X-ray photoelectron spectroscopy results also revealed that among the nitrogen fractions in the N-doped biochars, melamine modified biochar has the highest percentage of pyrrolic and pyridinic nitrogen (35.2% and 36.8%, respectively) compared to others. Urea modified biochar had the highest percentage of graphitic nitrogen (26.6%). Our results suggest that application-specific nitrogen-enriched biochar can be prepared by understanding how different nitrogen precursors interact with carbon surfaces.