Activated carbon is a promising material that has a broad application prospect.In this work, biomass (tea seed shell) was used to prepare activated carbon with KOH activation (referred to as AC), and nitrogen was doped in activated carbon using melamine as the nitrogen source (referred to as NAC-x, where x is the mass ratio of melamine and activated carbon). The obtained activated biomass carbon (activated bio-carbon) samples were characterized by Brunauer-Emmett-Teller (BET)-specific surface area analysis, ultimate analysis, X-ray photoelectron spectroscopy (XPS) analysis, Raman spectrum analysis, and X-ray diffraction (XRD) patterns. The specific surface areas of activated bio-carbons were 1503.20 m 2 /g (AC), 1064.54 m 2 /g (NAC-1), 1187.93 m 2 /g (NAC-2), 1055.32 m 2 /g (NAC-3), and 706.22 m 2 /g (NAC-4), revealing that nitrogen-doping process leads to decrease in specific surface area. XPS analysis revealed that the main nitrogen-containing functional groups were pyrrolic-N and pyridinic-N. The capacity of CO 2 capture and electrochemical performance of activated bio-carbon samples were investigated. The CO 2 capturing capacity followed this order: AC (3.15 mmol/g) > NAC-2 (2.75 mmol/g) > NAC-1 (2.69 mmol/g) > NAC-3 (2.44 mmol/g) > NAC-4 (1.95 mmol/g) at 298 K at 1 bar, which is consistent with the order of specific surface area. The specific surface area played a dominant role in CO 2 capturing capacity. As for supercapacitor, AC-4 showed the highest specific capacitance (168 F/g) at the current density of 0.5 A/g, but NAC-2 showed the best electrochemical performance (89 F/g) at 2 A/g. Nitrogen-containing functional groups and specific surface area both had an important impact on electrochemical performance. In general, NAC-3 and NAC-2 produced excellent electrochemical performance. Compared with NAC-3, less melamine was used to prepare NAC-2; therefore, NAC-2 was considered as the best activated bio-carbon for supercapacitor for 141 F/g (at 0.5 A/g), 108 F/g (at 1 A/g), and 89 F/g (at 2 A/g) in this work.

No abstract

No abstract

Microalgae is an excellent type of biomass for bio-energy production due to its high calorific value and fast growth. However, a large amount of ash would be generated during microalgae utilization. In this work, MCM41 was prepared from microalgae ash. The materials were calcined at different temperatures (450 C, 500 C, 550 C, and 600 C), and the effect of calcination temperature was investigated. Polyethyleneimine (PEI) was loaded in MCM41 by the impregnation method at different loading amounts (30%, 40%, 50%, and 60%). The CO 2 capturing capacity was measured. The results showed that the