TY  - EJOU
AU  - Chobsilp, Thanattha 
AU  - Treetong, Alongkot 
AU  - Yordsri, Visittapong 
AU  - Santasnachok, Mattana 
AU  - Charoeythornkhajhornchai, Pollawat 
AU  - Sukkasem, Jaruvit 
AU  - Wongwiriyapan, Winadda 
AU  - Muangrat, Worawut 

TI  - Surface Modification of Activated Carbon by Nitrogen Doping and KOH Activation for Enhanced Carbon Dioxide Adsorption Performance
T2  - Journal of Renewable Materials

PY  - 2025
VL  - 13
IS  - 11
SN  - 2164-6341

AB  - Nitrogen-doped activated carbon (N-AC) was successfully prepared by KOH-activation and nitrogen doping using ammonia (NH<sub>3</sub>) heat treatment. Coconut shell-derived activated carbon (AC) was heat-treated under NH<sub>3</sub> gas in the temperature range of 700°C–900°C. Likewise, the mixture of potassium hydroxide (KOH) and AC was heated at 800°C, followed by heat treatment under NH<sub>3</sub> gas at 800°C (hereafter referred to as KOH-N-AC800). Scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) method were utilized to analyze morphology, crystallinity, chemical bonding, chemical composition and surface area. The surface area and porosity of N-AC increased with increasing NH<sub>3</sub> heat treatment. Similarly, the nitrogen content in the N-AC increased from 3.23% to 4.84 at% when the NH<sub>3</sub> heat treatment was raised from 700°C to 800°C. However, the nitrogen content of N-AC decreased to 3.40 at% after using NH<sub>3</sub> heat treatment at 900°C. The nitrogen content of KOH-N-AC800 is 5.43 at%. KOH-N-AC800 and N-AC800 exhibited improvements of 33.66% and 26.24%, respectively, in CO<sub>2</sub> adsorption compared with AC. The enhancement of CO<sub>2</sub> adsorption of KOH-N-AC800 is attributed to the synergic effect of the nitrogen doping, high surface area, and porosity. The results exhibited that nitrogen sites on the surface play a more significant role in CO<sub>2</sub> adsorption than surface area and porosity. This work proposes the potential synergistic effect of KOH-activation and nitrogen doping for enhancing the CO<sub>2</sub> adsorption capacity of activated carbon.
KW  - Nitrogen-doped activated carbon; nitrogen doping; ammonia heat treatment; carbon dioxide adsorption; carbon capture; sustainable development goals

DO  - 10.32604/jrm.2025.02025-0111