Nitrogen-doped Carbon with Modulated Surface Chemistry and Porous Structure by a Stepwise Biomass Activation Process towards Enhanced Electrochemical Lithium-Ion Storage

Zhenzhen Nie,Zhenjun Wu,Xiuqiang Xie,Xiaobin Qiu,Nan Zhang,Yewei Huang,Beibei Ma

doi:10.1038/s41598-019-50330-w

Zhenzhen Nie, Zhenjun Wu + Show 5 more

Open Access

https://doi.org/10.1038/s41598-019-50330-w

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Journal: Scientific Reports	Publication Date: Oct 21, 2019
Citations: 27	License type: open-access

Affiliation: Hunan University

Abstract

Controllable conversion of biomass to value-added carbon materials is attractive towards a wide variety of potential applications. Herein, hydrothermal treatment and KOH activation are successively employed to treat the cheap and abundant camellia oleifera shell as a new carbon raw material. It is shown that this stepwise activation process allows the production of porous nitrogen-doped carbon with optimized surface chemistry and porous structure compared to the counterparts prepared by a single activation procedure. Benefiting from the modulated porous structure, the as-produced porous nitrogen-doped carbon electrode delivered a high reversible capacity of 1080 mAh g−1 at a current density of 100 mA g−1, which is 3.3 and 5.8 times as high as that of the carbon materials prepared by bare hydrothermal treatment or KOH activation, respectively. Moreover, the optimized surface composition of the porous nitrogen-doped carbon endows it with a highest initial Coulombic efficiency among the three samples, showing great potentials for practical applications. This work is expected to pave a new avenue to upgrade biomass to carbon materials with tunable surface properties and microstructures for target applications.

Highlights

Www.nature.com/scientificreports materials, during which a series of complex, concurrent and consecutive reactions occur before the as-prepared carbon materials are formed at a fixed high temperature[13,14,15]
Bare hydrothermal treatment or KOH activation was employed to treat the camellia oleifera shell, and the products are denoted as HTC and C-KOH, respectively
Hierarchical porous nitrogen-doped carbon materials have been successfully prepared from the cheap camellia oleifera shell as a new biomass precursor through a stepwise hydrothermal treatment and KOH activation process

Summary

Introduction

Www.nature.com/scientificreports materials, during which a series of complex, concurrent and consecutive reactions occur before the as-prepared carbon materials are formed at a fixed high temperature[13,14,15]. It should be noted that biomass-derived carbon materials often suffer from low initial Coulombic efficiency (ICE) due to the presence of abundant surface residues trapping Li-ions, such as oxygen-containing groups[21] In this regard, efforts on modulating the surface properties and microstructures toward enhancing the electrochemical performances (for example, ICE and specific capacity) of the biomass-derived carbon materials is highly desirable but has been lacking in literatures. When used as the anode materials for electrochemical Li-ion storage, the as-produced porous nitrogen-doped carbon exhibited superior performances compared to the carbon counterparts prepared by a single activation procedure of either hydrothermal treatment or KOH activation, including improved ICE, significantly increased specific capacity, and enhanced rate-capability

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