Title: Simultaneous activation and N-doping of hydrothermal carbons by NaNH₂: An effective approach to CO₂ adsorbents

Abstract

Synthesis of carbon materials with both large surface area and abundant heteroatoms is an important task in scientific research. Traditional approaches mostly proceed at extremely high temperature, and suffer from complex routes and/or expensive raw materials. NaNH₂ has been recently found to be able to not only etch C atoms to create nanochannels, but also substitute O species to introduce N species. In this work, an effective approach to N-doped porous carbons was realized by treating hydrothermal carbons (HTCs) with sodium amide (NaNH₂). The considerable amount of O species preserved in pristine HTCs enables the achievement in simultaneous activation and N-doping of HTCs by NaNH₂ at relatively moderate temperature (400~600 °C). The porous and chemical structure of NaNH₂-treated HTCs were characterized systematically. Although the pristine HTCs are almost non-porous and N-free, the specific surface areas and total N contents of prepared NaNH₂-treated HTCs reach 190~2430 m²/g and 0.78~6.57 wt.% respectively. Furthermore, the CO₂ capture performance of NaNH₂-treated HTCs was also examined considering their highly porous and N-doped nature. Interestingly, NaNH2-treated HTCs exhibit high CO₂ capacities, large CO₂/N₂ selectivities, fast CO₂ adsorption rate and excellent recyclability, endowing them with potential application as solid adsorbents for CO₂ capture.

Authors:

Huang, Kuan ^[1]; Li, Zi-Liang ^[1]; Zhang, Jia-Yin ^[1]; Tao, Duan-Jian ^[2]; Liu, Fujian ^[3]; Dai, Sheng ^[4]

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+ Show Author Affiliations

1. Nanchang Univ., Jiangxi (China). School of Resources Environmental and Chemical Engineering. Resource Utilization of Ministry of Education. Key Lab. of Poyang Lake Environment
2. Jiangxi Normal Univ., Nanchang (China). College of Chemistry and Chemical Engineering
3. Fuzhou Univ., Fujian (China). School of Chemical Engineering. National Engineering Research Center of Chemical Fertilizer Catalyst
4. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Chemistry; Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division

Publication Date:

Fri Jul 12 00:00:00 EDT 2019

Research Org.:

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division; USDOE

OSTI Identifier:

1785620

Alternate Identifier(s):

OSTI ID: 1779983

Grant/Contract Number:  

AC05-00OR22725

Resource Type:

Accepted Manuscript

Journal Name:

Journal of CO2 Utilization

Additional Journal Information:

Journal Volume: 33; Journal ID: ISSN 2212-9820

Publisher:

Elsevier

Country of Publication:

United States

Language:

English

Subject:

hydrothermal carbon; sodium amide; activation; nitrogen content; CO2 adsorption