Mesopore- and Macropore-Dominant Nitrogen-Doped Hierarchically Porous Carbons for High-Energy and Ultrafast Supercapacitors in Non-Aqueous Electrolytes

Rong Shao; Jin Niu; Jingjing Liang; Mengyue Liu; Zhengping Zhang; Meiling Dou; Yaqin Huang; Feng Wang

doi:10.1021/acsami.7b14390

Mesopore- and Macropore-Dominant Nitrogen-Doped Hierarchically Porous Carbons for High-Energy and Ultrafast Supercapacitors in Non-Aqueous Electrolytes

ACS Appl Mater Interfaces. 2017 Dec 13;9(49):42797-42805. doi: 10.1021/acsami.7b14390. Epub 2017 Dec 4.

Authors

Rong Shao^{1

2}, Jin Niu^{1

2}, Jingjing Liang^{1

2}, Mengyue Liu^{1

2}, Zhengping Zhang^{1

2}, Meiling Dou^{1

2}, Yaqin Huang¹, Feng Wang^{1

2}

Affiliations

¹ State Key Laboratory of Chemical Resource Engineering, Laboratory of Electrochemical Process and Technology for Materials, Beijing University of Chemical Technology , Beijing 100029, China.
² Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology , Beijing 100029, P. R. China.

PMID: 29168631
DOI: 10.1021/acsami.7b14390

Abstract

Non-aqueous electrolytes (e.g., organic and ionic liquid electrolytes) can undergo high working voltage to improve the energy densities of supercapacitors. However, the large ion sizes, high viscosities, and low ionic conductivities of organic and ionic liquid electrolytes tend to cause the low specific capacitances, poor rate, and cycling performance of supercapacitors based on conventional micropore-dominant activated carbon electrodes, limiting their practical applications. Herein, we propose an effective strategy to simultaneously obtain high power and energy densities in non-aqueous electrolytes via using a cattle bone-derived porous carbon as an electrode material. Because of the unique co-activation of KOH and hydroxyapatite (HA) within the cattle bone, nitrogen-doped hierarchically porous carbon (referred to as NHPC-HA/KOH) is obtained and possesses a mesopore- and macropore-dominant porosity with an ultrahigh specific surface area (2203 m² g^-1) of meso- and macropores. The NHPC-HA/KOH electrodes exhibit superior performance with specific capacitances of 224 and 240 F g^-1 at 5 A g^-1 in 1.0 M TEABF₄/AN and neat EMIMBF₄ electrolyte, respectively. The symmetric supercapacitor using NHPC-HA/KOH electrodes can deliver integrated high energy and power properties (48.6 W h kg^-1 at 3.13 kW kg^-1 in 1.0 M TEABF₄/AN and 75 W h kg^-1 at 3.75 kW kg^-1 in neat EMIMBF₄), as well as superior cycling performance (over 89% of the initial capacitance after 10 000 cycles at 10 A g^-1).

Keywords: biomass; co-activation; hierarchically porous carbons; non-aqueous electrolytes; supercapacitor.