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A High-capacity Hard Carbon Pyrolysed from Subbituminous Coal as Anode for Sodium-ion Batteries Haiyan Lu, Shaofa Sun, Lifen Xiao, Jiangfeng Qian, Xinping Ai, Hanxi Yang, An-Hui Lu, and Yuliang Cao ACS Appl. Energy Mater., Just Accepted Manuscript • DOI: 10.1021/acsaem.8b01784 • Publication Date (Web): 04 Jan 2019 Downloaded from http://pubs.acs.org on January 6, 2019

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ACS Applied Energy Materials

A High-capacity Hard Carbon Pyrolysed from Subbituminous Coal as Anode for Sodium-ion Batteries Haiyan Lua†, Shaofa Sunb†, Lifen Xiaoc, Jiangfeng Qiana, Xinping Aia, Hanxi Yanga, An-Hui Lud and Yuliang Cao*a a Hubei

Key Laboratory of Electrochemical Power Sources, College of Chemistry and Molecular

Sciences, Wuhan University, Wuhan 430072, China. E-mail: [email protected] b School

of Nuclear Technology & Chemistry and Biology, Hubei University of Science and

Technology, Xianning 437100, China. c State

Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan

University of Technology, Wuhan 430072, China. d

State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of

Technology, Dalian 116024, China. *Corresponding author. E-mail: [email protected] (Yuliang Cao)

Abstract

A pyrolysed subbituminous carbon is synthesized through a simple one-step carbonization process as low-cost and high-capacity anode for sodium-ion batteries (SIB). The pyrolysed subbituminous carbon, SHC-1300 anode shows high Na storage capacity of 291 mA h g-1 at 20 mA g-1 and high initial coulombic efficiency of 79.5%, as well as stable cycling performance, exhibiting a promising alternative anode for affordable and high-performance SIB. Furthermore, according to the investigation of 1

ACS Paragon Plus Environment

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the electrochemical performance and structural characterizations, the SHC-1300 pyrolysed from subbituminous coal with flexible structure demonstrates a better electrochemical performance compared with the BHC-1300 pyrolysed from bituminous coal with rigid structure. The sodium storage mechanism and structural evolution reported in this work may give a new prospect for the selection of pyrolysed carbon materials for high-performance sodium-ion batteries.

Keywords: Subbituminous coal; hard carbon; anode; pyrolysed carbon; sodium storage mechanism; sodium-ion battery

1. Introduction

Sodium-ion batteries (SIB) have recently received wide attention to develop sustainable and less expensive large-scale electric storage owing to their low cost, easy accessibility and abundance of Na resources, compared to their lithium counterparts.1-10 However, finding high-performance electrode materials for both cathode and anode is a major challenge in realizing advanced sodium storage, due to the sluggish kinetics of the sodium ion with larger ion radius and unstable structure of the materials during cycling process compared to lithium ion.8 Anode material has always been a focus because its performance (voltage, capacity, cycling and cost) determines the applied possibility of SIB. There are several kinds of anodic materials reported with considerable Na storage capacities and good cycling performance,

2


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including carbon11-17, alloying18-24, phosphate25-28 and so on. Among the anode materials, carbon material is one of the most potential and practicable anodes for SIB based on low sodium storage potential (~ 0.1 V vs. Na+/Na for hard carbon), high reversible capacity (~ 300 mA h g-1) and easy accessibility, which is beneficial for developing high-performance SIB.11, 13, 29-31 Unlike lithium-ion batteries, graphite anode generally used in commercial lithium-ion batteries, has hardly available capacity in usually carbonate electrolyte because of the failure to form graphite intercalation compound (GIC), which cannot be used as a host material for SIB.32 However, a large amount of non-graphitic carbon materials (hard and soft carbon) exhibited an available reversible capacity of 200-300 mA h g-1 as SIB anode materials due to their large carbon layer spacing or abundant void in microdomain.11-13,

29, 33-35

Cao et al. reported that hollow carbon nanowires

could exhibit a reversible capacity of 258 mA h g-1 with a stable cycling performance as an anode for SIB.13 Luo et al. prepared carbon nanofibers derived from cellulose, which could deliver a capacity of 255 mA h g-1 at 40 mA g-1 for sodium storage.35 Besides, low-cost carbon material is also a key factor for the application of large-scale energy storage SIB. Some waste biomass have been investigated as low-cost and high-performance anode materials.12,

36-38

A carbon nanosheets derived from peat

moss delivered a high capacity of 298 mA h g-1 at 50 mA g-1 for SIB.12 Carbon nanoparticles derived from coconut oil exhibited a capacity of 278 mA h g-1 at 100 mA g-1 for sodium storage.38 A hard carbon anodes derived from nanocelluloses exhibited a high capacity of 386 mA h g-1 along with a stable cycling performance.39

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However, the carbon materials derived from these biomass materials have large specific surface area and low carbon-forming ratio after carbonization, leading low initial coulombic efficiency and increase of manufacturing costs. Furthermore, the carbon anode with high specific surface area can enhance the capacity of the material, but also cause the decrease of initial coulombic efficiency due to more irreversible electrolyte decomposition.40-42 Coal is low cost and high carbon content material.43-44 Coal can generally be divided into four types: anthracite, bituminous, sub-bituminous and lignite, according to the volatiles contents the coal contained and the heating energy amount.45-46 Recently Li et al. reported that a pyrolysed anthracite carbon delivered a reversible capacity of 222 mA h g-1 and stable cycling performance for sodium storage,44 showing affordable and high-performance carbon anode. Due to different aging ages in the underground, four types of coal exhibit different chemical structure. For example, anthracite with long aging age (high degree of carbonization) includes more hydroaromatic and cross-linking structure, while lignite with short aging age has less hydroaromatic structure (low degree of carbonization) and some small molecular organic materials. The different in structural characterizations for various coals would cause different electrochemical properties in sodium storage. Besides, among all the types of coal, the subbituminous with short aging age has the lowest price compared to the others and large reserves in the world (Table S1), which has more application advantages for low-cost sodium storage. Herein we investigated a low-cost and high-performance hard carbon anode material for SIB using subbituminous as a

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precursor through simple one-step carbonization process. The hard carbon can deliver a high capacity of 291 mA h g-1 at 20 mA g-1 and high initial coulombic efficiency (ICE) of ~ 80 %, as well as stable cycling performance. Also, the different electrochemical performances between the pyrolysed subbituminous and bituminous carbons with different aging ages were revealed to understand the impact of the structure of the raw carbon on sodium storage.

2. Material and methods 2.1 Material preparation and characterization The pyrolysed subbituminous carbon was prepared by the pyrolysis of the subbituminous (Hongshaquan mining area, Xinjiang province, China). Before carbonization, the subbituminous was only ball-milled without further treatment. Then the subbituminous powders were heated at 1000 ºC, 1300 ºC and 1500 ºC respectively for 2h in Ar atmosphere at a heating rate of 1 ºC min-1. The pyrolysed subbituminous hard carbon materials were noted as SHC-1000, SHC-1300 and SHC-1500 respectively. For comparison, the pyrolysed bituminous hard carbon was prepared in the same way and was noted as BHC-1300 (Binxian mining area, Shanxi province, China). The pyrolysed subbituminous carbon was characterized by scanning electron microscopy (SEM, ULTRA/PLUS, ZEISS), transmission electron microscopy (TEM, JEOL,

JEM-2010-fef),

X-ray

diffraction

(XRD,

Bruker

D8

Advance),

thermogravimetric analyzer (Diamond TG/DTA 6300), Raman spectroscopy

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(Renishaw in Via, Renishaw, 532 nm excitation wavelength), X- ray Fluorescence Spectrometer (XRF, S4 Pioneer, Bruker AXS). The specific surface area of the pyrolysed carbon was measured by the Brunauer-Emmett-Teller (BET) method through N2 adsorption-desorption measurements (Micromeritics, ASAP 2020). The mesopore pore size distribution was calculated by the Barret-Joyner-Halenda (BJH) method and the micropore pore size distribution was calculated by the Horvath-Kawazoe method. 2.2 Electrochemical measurements The pyrolysed subbituminous carbon anodes were prepared by mixing 80 wt% the pyrolysed subbituminous, 10 wt% Super P, 10 wt% polyacrylic acid (PAA, 25 wt%) to form a slurry and then spreading the mixed slurry onto the Cu foil and dried at 100 ºC overnight under vacuum. The electrolyte was 1 M NaClO4 dissolved in ethylene (EC) and diethyl carbonate (DEC) (1:1 in volume). A Na disk was home-made as the counter electrode and a Celgard 2400 microporous membrane was used as the separator. All the cells were assembled in the Argon-filled glove box. The galvanostatic charge/discharge tests were carried out by a LAND cycler (Wuhan Kingnuo Electronic Co., China). Cyclic voltammetric (CV) measurements were carried out with the coin cell using a CHI 660C electrochemical workstation (ChenHua Instruments Co., China) at a scan rate of 0.1 mV s-1.

3. Results and Discussion 3.1 Morphological and structural characterizations

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The morphological and structural characterizations of the pyrolysed subbituminous hard carbon (SHC) are shown in Figure 1. Figure 1a showed X-ray diffraction (XRD) patterns of the SHCs pyrolysed at different temperature. Associating with the X- ray Fluorescence Spectrometer (XRF) results (Table S2), the main diffraction peaks of the SHC can be indexed to the carbon, the hexagonal SiO2 (JCPDS no. 47-1144) and cubic Al2O3 (JCPDS no. 47-1292), suggesting that the main impurities are silicate and aluminate due to no further purified treatment for raw subbituminous carbon. From the scanning electron microscopy (SEM) image (Figure 1b), the SHC-1300 appears to be uneven granular morphology with an average size of 10 μm. The Raman spectra of the SHC with different temperature were displayed in Figure 1c. There are two separate peaks of the carbon, which can be defined as the D peak at about 1350 cm-1 and the G peak at about 1590 cm-1. The G peak is ascribed to the bond stretching of sp2 carbon atoms in both rings and chains, while the D peak is attributed to the breathing modes of the sp2 carbon atoms in the rings.47 The fitting of G peak and D peak are shown in Figure S3. The ID/IG corresponds to the ratio of peak areas using Gaussians lineshape.48 The ID/IG ratio for SHC-1000, SHC-1300 and SHC-1500 decreases from 1.92 to 1.48, to 1.13, indicating the formation of the more integrated hexacyclic structure of the carbon and the decrease of the defects in carbon structure with increasing temperature. BET specific surface area is also an important tool to illustrate the carbon structure. As shown in Figure S4, nitrogen adsorption-desorption isotherms of the SHCs were carried out. All the adsorption curves of the SHCs display type Ⅱ/Ⅲ isotherms. The BET specific surface area, which was calculated by

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the Brunauer-Emmett-Teller (BET) method, was 35.3 4.53 and 3.14 m2 g-1 for the SHC-1000, SHC-1300 and SHC-1500 respectively. It can be seen that the BET surface area shows a tendency of declining as the pyrolyzed temperature increases. The transmission electron microscopy (TEM) images of the SHCs pyrolysed at 1000 ºC, 1300 ºC and 1500 ºC were illustrated in Figure 1d-f. With increasing pyrolysis temperature, it was clearly found that the ordering of the carbon layer gradually increases, which is in accordance with the Raman results (Figure 1c). The ordering layered structure and appropriate interlayer distance facilitate sodium ion intercalation to obtain high capacity.13, 49-50

Figure 1. (a) XRD patterns of the pyrolysed hard carbons from subbituminous coal (SHCs) in different temperature; (b) SEM image of SHC-1300; (c) Raman spectra of the SHCs with different temperature; TEM images of (d) SHC-1000, (e) SHC-1300, (f) SHC-1500. 8


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3.2 Electrochemical performances of the SHCs The electrochemical performances of the SHCs at different carbonization temperature were illustrated in Figure 2. The initial galvanostatic discharge and charge curves of the SHC electrodes at a current rate of 20 mA g-1 are shown in Figure 2a. It can be seen that the reversible capacities of the SHC-1000, SHC-1300 and SHC-1500 electrodes are 234, 292 and 284 mA h g-1, along with initial coulombic efficiency of 69.4, 79.5 and 72.8 %, respectively. All the discharge curves can be divided into two parts: a sloping-potential region (voltage ranges from 2 V to 0.1 V) and a plateau-potential region (voltage ranges from 0.1 V to 0 V). To figure out the capacity contribution from both sloping and plateau regions, a summary of capacity potential distribution of SHCs hard carbon electrodes were carried out. As Figure S5 exhibits, the slope capacity is 127.8, 115.2, 102.5 mA h g-1 for SHC-1000, SHC-1300 and SHC-1500 respectively, showing a declining trend as temperature increases. While the plateau capacity, which is the main part of the reversible capacity, is 106.5, 176.4, and 181.7 mA h g-1 for SHC-1300 and SHC-1500 respectively, showing an increasing trend as temperature increases. Hard carbon materials pyrolyzed in higher temperature has more ordered graphite-like nanodomain, less defect and lower specific surface area, which results in increasing plateau capacity and decreasing slope capacity. The results are consistent with the “adsorption-insertion” mechanism: the sloping-voltage region should be related to the adsorption characteristics on the active sites (defects, edges, functional groups and so on) on the carbon surface while

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the plateau-voltage region should be regard as the Na ion intercalation between graphene sheets.13,

49-50

The two opposite trends result in a “volcano” shape of the

reversible capacity, which makes the SHC-1300 electrode exhibit a higher reversible capacity than the SHC-1500 electrode. Cycling performance is also a crucial factor to evaluate the electrochemical performance. Figure S6 exhibits the cycling performance of the SHCs with different temperature. It is found that the capacity retention of the SHC-1000, SHC-1300 and SHC-1500 electrodes over 50 cycles are 72.5%, 94.9% and 93.3% respectively. It could be discovered that the SHC-1300 electrode shows more stable cycling performance. All in all, it allows us to conclude that SHC-1300 delivers the best electrochemical performance. Figure 2b showed the initial two cyclic voltammogram (CV) curves of the SHC-1300 electrode between 0.01 V and 2.0 V at a scan rate of 0.01 mV s-1. During the first negative scan, an irreversible peak is found at around 0.75 V and disappears at in the second cycle, corresponding to the irreversible decomposition of the electrolyte and the formation of solid-electrolyte interface (SEI) films. The pair of oxidation/reduction peaks occurring at about 0/0.1 V corresponds to the low-potential plateau in the charge and discharge curves (Figure 2a), which is ascribed to the Na ion intercalation between graphene sheets, similar to Li ion intercalation into graphite.51-52 Compared with the initial two cyclic voltammogram (CV) curves of the SHC-1000 and SHC-1500 electrodes (Figure S7), it is obviously found that the area of the broad reduction peak of the SHC-1000 electrode is larger than that of the SHC-1300 and

10


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SHC-1500 electrodes. It indicates that the SHC-1000 electrode forms a thick SEI film and exhibits more irreversible capacity compared with the SHC-1300 and SHC-1500 electrodes. It is consistent with the above galvanostatic charge–discharge experimental results. Figure 2c depicted the rate behavior of the SHC-1300 electrode. The SHC-1300 electrode delivered a high capacity of 291.6 mA h g-1 at small current density of 20 mA g-1. When the current density increases to 400 mA g-1, the SHC-1300 electrode exhibited a capacity of only 57 mA h g-1. The capacity loss mainly occurred at low-potential plateau region, due to larger polarization at high current density.53-54 However, when the current density got back to 20 mA g-1, the capacity of the SHC-1300 still turned back to 279 mA h g-1, suggesting high electrochemical reversibility. The SHC-1300 also showed excellent capacity retention of 82 % after 150 cycles at 50 mA g-1 (Figure 2d). Table S3 compares the electrochemical performance of the SHC-1300 prepared in this work with other carbon electrode materials in NIBs reported in literature. It can be seen that the SHC-1300 reported in this work has a considerable highly reversible capacity and high initial coulombic efficiency, as compared to the previous results. The excellent electrochemical performance of the SHC-1300 with low-cost raw material and simple synthesis process without further purified treatment implies that the SHC-1300 is very competitive anode material for low-cost and high-performance SIB.

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Figure 2. Electrochemical performance of the pyrolysed subbituminous electrodes and the pyrolysed bituminous electrodes in different carbonization temperature. (a) The initial galvanostatic discharge and charge curves of the pyrolysed subbituminous electrodes with different temperature at a current rate of 20 mA g-1; (b) The first two cyclic voltammogram (CV) curves of the SHC-1300 electrode at a scan rate of 0.01 mV s-1; (c) Rate capability of the SHC-1300 electrode at various current rates from 20 to 400 mA g-1; (d) Cycling performance of the SHC-1300 electrode at a current rate of 50 mA g-1 (The current rate is 20 mA g-1 in the first four cycles).

3.3 Comparison between the pyrolysed subbituminous and bituminous hard carbon The different types of coal have different chemical structure (molecular size, impurity, functional group and so on) due to different aging age, which is bound to 12


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affect the electrochemical performance of the pyrolysed carbon. Li et al. have reported that a pyrolysed anthracite carbon (long aging age, high rank coal) delivered a reversible capacity of 222 mA h g-1 and stable cycling performance for sodium storage,44 but exhibited lower capacity compared with the present subbituminous carbon (short aging age, low rank coal) in this work. In order to further elucidate the correlation between the electrochemical performance and structure of coal to develop low-cost and high-performance hard carbon anode, two types of coal (subbituminous and bituminous coal) with relative low cost were chosen to investigate their electrochemical performance. The subbituminous and bituminous coal chosen have almost the same mineral element and almost the same content of ash as well, as the XRF results (Table S2), TG results (Figure S1) and XRD results (Figure S2) illustrated. Subbituminous coal is called as the low rank of coal with low heat content, while bituminous coal is considered to be the high rank of coal.45-46 Figure S10 illustrated the typical structural model of the subbituminous (Hatcher’s model45 ) and bituminous (Shinn’s model46) coal. Compared to the bituminous coal, the subbituminous coal has lower ratio of carbon to oxygen, smaller molecular size and less hydroaromatic structure, exhibiting stronger molecular flexibility when heated. As shown in the results of the element analysis (Table S2), the subbituminous coal has lower carbon content and lower carbon-to-oxygen ratio, which is in agreement with the above structural model. Figure 3 presents the electrochemical performance, morphology and structural characterization of the SHC-1300 and BHC-1300 pyrolysed from the subbituminous

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and bituminous coal, respectively. Figure 3a exhibited the initial galvanostatic discharge and charge curves of the SHC-1300 and BHC-1300 electrodes at a current rate of 20 mA g-1.The BHC-1300 electrode provided a reversible capacity of only 225 mA h g-1 with a coulombic efficiency of 67.9 %, which is similar to that (222 mA h g-1) for the pyrolysed anthracite coal reported by Li et al.34, but lower than that (291 mA h g-1) for the SHC-1300 electrode (Figure 2a). It is consistent with the XPS results (Figure S9). Figure S9 shows C 1s spectra of the SHC-1300 and BHC-1300 electrodes discharged to 0.01 V. Both spectra exhibit five additional peaks at 284.2, 285.8, 287.5, 288.3 and 289.2 eV, which are ascribed to sp2, CH2, C–O, O=C–O and CO3 environment of carbon, respectively.55-56 These peaks correspond to the different carbonaceous species that compose the SEI layer, and are similar to those observed for hard carbon electrodes in Na-ion batteries.55-57 Compared with the BHC-1300, the SHC-1300 electrode shows a relatively high sp2 carbon peak and an inapparent SEI feature, indicating that a thin SEI layer is covered on the surface.58 It is proposed to be useful to improve the electrochemical performance, resulting in the higher capacity and the higher initial coulombic efficiency. These results indicate that the structure of the raw material has an important effect on the electrochemical performance. To disclose their correlation, some structural characterizations of the SHC-1300 and BHC-1300 were investigated and compared. Raman spectrum of the SHC-1300 and BHC-1300 were shown in Figure 3b. The ID/IG ratio for the SHC-1300 and BHC-1300 are 1.96 and 1.98 respectively, exhibiting that there are more ordered structure in the SHC-1300. Nitrogen adsorption–desorption measurements of the

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SHC-1300 and BHC-1300 were carried out to compare the surface area and porous structure of two kinds of pyrolysed carbons (Figure 3c). The Brunauer–Emmett– Teller (BET) specific surface area was calculated as 4.53 m2 g-1 for the SHC-1300, lower than those (13.93 m2 g-1) for the BHC-1300, respectively.

TEM image was

conducted to further reveal the microstructure of the BHC-1300 (Figure 3d). Compared to TEM image of the SHC-1300 (Figure 1e), the BHC-1300 showed obviously more disorder structure. All the above results exhibits that the BHC-1300 contains less crystalline turbostratic nanodomains, higher surface area and more microporous structure.

Figure 3. (a) The initial galvanostatic discharge and charge curves of the SHC-1300 and BHC-1300 at a current rate of 20 mA g-1; (b) Raman spectra of SHC-1300 and

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BHC-1300; (c)N2 adsorption-desorption isothermal curves and pore distribution of SHC-1300 and BHC-1300; (d) TEM image of BHC-1300. To schematically describe the microstructural evolution, the structural scheme of the pyrolysis mechanism of the subbituminous and bituminous coal was illustrated in Figure S10c. Benefiting from small molecular size and less hydroaromatic structure, the molecular chain of the subbituminous coal is easy to become more flexible with increasing pyrolysis temperature, causing that the carbon layers tend to stack together. Thus, the SHC-1300 shows more ordering carbon layer structure and smaller surface area and micropore volume, which facilitates Na ion intercalation in the carbon layers and decreases the irreversible decomposition of the electrolyte. However, for the bituminous coal with more hydroaromatic structure, the rigid molecular structure impedes the stacking of the carbon layers due to large steric hindrance, leading to the formation of the disordering structure and micropore. The structural evolution also is in accordance with the observation of the Raman, BET and TEM measurement (Figure 3b-d). Thus, the BHC-1300 with disordering and microporous structure shows lower plateau capacity and ICE (Figure 3a) compared to the SHC-1300 according to the “adsorption-insertion” mechanism.13,

49-50

These results further demonstrate that

the integrity of the carbon layer structure is very important to improve the sodium storage capacity of the carbon anode, particularly the low-potential-plateau capacity.

4. Conclusions A low-cost and high-performance hard carbon pyrolysed from the subbituminous

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coal as an anode for sodium ion batteries through simple one-step carbonization process. When the pyrolysis temperature increases to 1300 ºC, the pyrolysed subbituminous carbon (SHC-1300) can deliver a high capacity of 291 mA h g-1 at 20 mA g-1 with an initial coulombic efficiency of 79.5%, exhibiting great promising and affordable anode material for low-cost SIB. Moreover, the electrochemical performance and relative mechanism of the pyrolysed carbon derived from different types of the coal also were investigated. The results showed that the SHC-1300 pyrolysed from the subbituminous coal with the flexible molecular structure demonstrated better electrochemical performance compared with the bituminous coal with rigid molecular structure, which provides a new approach to choose the carbon precursor with appropriate molecular structure for developing high-performance and low-cost carbon anode materials for large-scale sodium-ion batteries. ASSOCIATED CONTENT Supporting Information Available: The price and production of typical precursors for carbon materials; XRF results and ultimate analysis; TG curves; XRD patterns; Fitted Raman spectra; Nitrogen adsorption-desorption isotherms; Summary of capacity potential distribution; Cycling performance; CV curves; XPS C 1s spectra; Average structural unit model; Structural Scheme.

Acknowledgments H. Lu and S. Sun contributed equally to this work. We thank financial support by the

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National Key Research Program of China (No. 2016YFB0901500), National Natural Science

Foundation

of

China

(Nos.

21673165

and

21333007).

We

also appreciate the raw coals provided by the state key laboratory of coal combustion, Huazhong University of Science and Technology.

Reference: (1) Fang, Y.; Xiao, L.; Chen, Z.; Ai, X.; Cao, Y.; Yang, H. Recent Advances in Sodium-Ion Battery Materials. Electrochemical Energy Reviews 2018, 1, 294-323. (2) Kim, S.-W.; Seo, D.-H.; Ma, X.; Ceder, G.; Kang, K. Electrode Materials for Rechargeable Sodium-Ion Batteries: Potential Alternatives to Current Lithium-Ion Batteries. Adv. Energy Mater. 2012, 2, 710-721. (3) Palomares, V.; Serras, P.; Villaluenga, I.; Hueso, K. B.; Carretero-González, J.; Rojo, T. Na-ion batteries, recent advances and present challenges to become low cost energy storage systems. Energy Environ. Sci. 2012, 5, 5884-5901. (4) Slater, M. D.; Kim, D.; Lee, E.; Johnson, C. S. Sodium-Ion Batteries. Adv. Funct. Mater. 2013, 23, 947-958. (5) Wang, L. P.; Yu, L. H.; Wang, X.; Srinivasan, M.; Xu, Z. C. J. Recent developments in electrode materials for sodium-ion batteries. J. Mater. Chem. A 2015, 3, 9353-9378. (6) Kim, H.; Kim, H.; Ding, Z.; Lee, M. H.; Lim, K.; Yoon, G.; Kang, K. Recent Progress in Electrode Materials for Sodium-Ion Batteries. Adv. Energy Mater. 2016, 6, 1600943.

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(7) Kundu, D.; Talaie, E.; Duffort, V.; Nazar, L. F. The Emerging Chemistry of Sodium Ion Batteries for Electrochemical Energy Storage. Angew. Chem., Int. Ed. 2015, 54, 3431-3448. (8) Chevrier, V. L.; Ceder, G. Challenges for Na-ion Negative Electrodes. J. Electrochem. Soc. 2011, 158, A1011-A1014. (9) Yabuuchi, N.; Kubota, K.; Dahbi, M.; Komaba, S. Research Development on Sodium-Ion Batteries. Chem. Rev. 2014, 114, 11636-11682. (10)Feng, L.; Zhen, Z. Micro/Nanostructured Materials for Sodium Ion Batteries and Capacitors. Small 2018, 14, 1702961. (11)Stevens, D. A.; Dahn, J. R. High capacity anode materials for rechargeable sodium-ion batteries. J. Electrochem. Soc. 2000, 147, 1271-1273. (12)Ding, J.; Wang, H. L.; Li, Z.; Kohandehghan, A.; Cui, K.; Xu, Z. W.; Zahiri, B.; Tan, X. H.; Lotfabad, E. M.; Olsen, B. C.; Mitlin, D. Carbon Nanosheet Frameworks Derived from Peat Moss as High Performance Sodium Ion Battery Anodes. Acs Nano 2013, 7, 11004-11015. (13)Cao, Y. L.; Xiao, L. F.; Sushko, M. L.; Wang, W.; Schwenzer, B.; Xiao, J.; Nie, Z. M.; Saraf, L. V.; Yang, Z. G.; Liu, J. Sodium Ion Insertion in Hollow Carbon Nanowires for Battery Applications. Nano Lett. 2012, 12, 3783-3787. (14)Wen, Y.; He, K.; Zhu, Y. J.; Han, F. D.; Xu, Y. H.; Matsuda, I.; Ishii, Y.; Cumings, J.; Wang, C. S. Expanded graphite as superior anode for sodium-ion batteries. Nat. Commun. 2014, 5, 4033.

19



Page 20 of 26

(15)Li, W.; Zhou, M.; Li, H. M.; Wang, K. L.; Cheng, S. J.; Jiang, K. A high performance sulfur-doped disordered carbon anode for sodium ion batteries. Energy Environ. Sci. 2015, 8, 2916-2921. (16)Bin, D.-S.; Li, Y.; Sun, Y.-G.; Duan, S.-Y.; Lu, Y.; Ma, J.; Cao, A.-M.; Hu, Y.-S.; Wan, L.-J. Structural Engineering of Multishelled Hollow Carbon Nanostructures for High-Performance Na-Ion Battery Anode. Adv. Energy Mater. 2018, 8, 1800855. (17)Sun, X.; Wang, C.; Gong, Y.; Gu, L.; Chen, Q.; Yu, Y. A Flexible Sulfur-Enriched Nitrogen Doped Multichannel Hollow Carbon Nanofibers Film for High Performance Sodium Storage. Small 2018, 14, 1802218. (18)Qiu, S.; Wu, X. Y.; Xiao, L. F.; Ai, X. P.; Yang, H. X.; Cao, Y. L. Antimony Nanocrystals Encapsulated in Carbon Microspheres Synthesized by a Facile Self-Catalyzing Solvothermal Method for High-Performance Sodium-Ion Battery Anodes. ACS Appl. Mater. Interfaces 2016, 8, 1337-1343. (19)Xiao, L.; Cao, Y.; Xiao, J.; Wang, W.; Kovarik, L.; Nie, Z.; Liu, J. High capacity, reversible alloying reactions in SnSb/C nanocomposites for Na-ion battery applications. Chem. Commun. 2012, 48, 3321-3323. (20)Wu, L.; Pei, P.; Mao, R. J.; Wu, F. Y.; Wu, Y.; Qian, J. F.; Cao, Y. L.; Ai, X. P.; Yang, H. X. SiC-Sb-C nanocomposites as high-capacity and cycling-stable anode for sodium-ion batteries. Electrochim. Acta 2013, 87, 41-45.

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Page 21 of 26 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(21)Wu, L.; Hu, X. H.; Qian, J. F.; Pei, F.; Wu, F. Y.; Mao, R. J.; Ai, X. P.; Yang, H. X.; Cao, Y. L. Sb-C nanofibers with long cycle life as an anode material for high-performance sodium-ion batteries. Energy Environ. Sci. 2014, 7, 323-328. (22)Wu, L.; Lu, H. Y.; Xiao, L. F.; Qian, J. F.; Ai, X. P.; Yang, H. X.; Cao, Y. L. A tin(II) sulfide-carbon anode material based on combined conversion and alloying reactions for sodium-ion batteries. J. Mater. Chem. A 2014, 2, 16424-16428. (23)Wu, L.; Hu, X. H.; Qian, J. F.; Pei, F.; Wu, F. Y.; Mao, R. J.; Ai, X. P.; Yang, H. X.; Cao, Y. L. A Sn-SnS-C nanocomposite as anode host materials for Na-ion batteries. J. Mater. Chem. A 2013, 1, 7181-7184. (24)Qian, J. F.; Chen, Y.; Wu, L.; Cao, Y. L.; Ai, X. P.; Yang, H. X. High capacity Na-storage and superior cyclability of nanocomposite Sb/C anode for Na-ion batteries. Chem. Commun. 2012, 48, 7070-7072. (25) Qian, J. F.; Wu, X. Y.; Cao, Y. L.; Ai, X. P.; Yang, H. X. High Capacity and Rate Capability of Amorphous Phosphorus for Sodium Ion Batteries. Angew. Chem., Int. Ed. 2013, 52, 4633-4636. (26)Li, W. J.; Chou, S. L.; Wang, J. Z.; Liu, H. K.; Dou, S. X. Simply Mixed Commercial Red Phosphorus and Carbon Nanotube Composite with Exceptionally Reversible Sodium-Ion Storage. Nano Lett. 2013, 13, 5480-5484. (27)Zhu, Y.; Wen, Y.; Fan, X.; Gao, T.; Han, F.; Luo, C.; Liou, S.-C.; Wang, C. Red Phosphorus Single-Walled Carbon Nanotube Composite as a Superior Anode for Sodium Ion Batteries. Acs Nano 2015, 9, 3254-3264.

21



Page 22 of 26

(28)Fang, Y.; Liu, Q.; Xiao, L.; Rong, Y.; Liu, Y.; Chen, Z.; Ai, X.; Cao, Y.; Yang, H.; Xie, J.; Sun, C.; Zhang, X.; Aoun, B.; Xing, X.; Xiao, X.; Ren, Y. A Fully Sodiated NaVOPO4 with Layered Structure for High-Voltage and Long-Lifespan Sodium-Ion Batteries. Chem 2018, 4, 1167-1180. (29)Stevens, D. A.; Dahn, J. R. The mechanisms of lithium and sodium insertion in carbon materials. J. Electrochem. Soc. 2001, 148, A803-A811 (30)Komaba, S.; Murata, W.; Ishikawa, T.; Yabuuchi, N.; Ozeki, T.; Nakayama, T.; Ogata, A.; Gotoh, K.; Fujiwara, K. Electrochemical Na Insertion and Solid Electrolyte Interphase for Hard-Carbon Electrodes and Application to Na-Ion Batteries. Adv. Funct. Mater. 2011, 21, 3859-3867. (31)Damien, S.; Brahim, O.; Biwei, X.; Daniel, C.; Xiaolin, L.; Teófilo, R. From Charge Storage Mechanism to Performance: A Roadmap toward High Specific Energy Sodium‐Ion Batteries through Carbon Anode Optimization. Adv. Energy Mater. 2018, 8, 1703268. (32) Udod, I. A. Sodium-graphite intercalation compound of the first stage: two-dimensional structure and stability. Synth. Met. 1997, 88, 127-131. (33)Doeff, M. M.; Ma, Y. P.; Visco, S. J.; Dejonghe, L. C. ELECTROCHEMICAL INSERTION OF SODIUM INTO CARBON. J. Electrochem. Soc. 1993, 140, L169-L170. (34)Kim, Y. J.; Wu, W.; Chun, S. E.; Whitacre, J. F.; Bettinger, C. J. Biologically derived melanin electrodes in aqueous sodium-ion energy storage devices. Proc. Natl. Acad. Sci. U. S. A. 2013, 110, 20912-20917.

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Page 23 of 26 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


(35)Luo, W.; Schardt, J.; Bommier, C.; Wang, B.; Razink, J.; Simonsen, J.; Ji, X. L. Carbon nanofibers derived from cellulose nanofibers as a long-life anode material for rechargeable sodium-ion batteries. J. Mater. Chem. A 2013, 1, 10662-10666. (36)Hong, K. L.; Qie, L.; Zeng, R.; Yi, Z. Q.; Zhang, W.; Wang, D.; Yin, W.; Wu, C.; Fan, Q. J.; Zhang, W. X.; Huang, Y. H. Biomass derived hard carbon used as a high performance anode material for sodium ion batteries. J. Mater. Chem. A 2014, 2, 12733-12738. (37) Ding, J.; Wang, H. L.; Li, Z.; Cui, K.; Karpuzov, D.; Tan, X. H.; Kohandehghan, A.; Mitlin, D. Peanut shell hybrid sodium ion capacitor with extreme energy-power rivals lithium ion capacitors. Energy Environ. Sci. 2015, 8, 941-955. (38)Gaddam, R. R.; Yang, D.; Narayan, R.; Raju, K.; Kumar, N. A.; Zhao, X. S. Biomass derived carbon nanoparticle as anodes for high performance sodium and lithium ion batteries. Nano Energy 2016, 26, 346-352. (39)Gaddam, R. R.; Jiang, E.; Amiralian, N.; Annamalai, P. K.; Martin, D. J.; Kumar, N. A.; Zhao, X. S. Spinifex nanocellulose derived hard carbon anodes for high-performance sodium-ion batteries. Sustainable Energy Fuels 2017, 1, 1090-1097. (40)Gaddam, R. R.; Farokh Niaei, A. H.; Hankel, M.; Searles, D. J.; Kumar, N. A.; Zhao, X. S. Capacitance-enhanced sodium-ion storage in nitrogen-rich hard carbon. J. Mater. Chem. A 2017, 5, 22186-22192.

23



Page 24 of 26

(41)Kumar, N. A.; Gaddam, R. R.; Varanasi, S. R.; Yang, D.; Bhatia, S. K.; Zhao, X. S. Sodium ion storage in reduced graphene oxide. Electrochim. Acta 2016, 214, 319-325. (42)Zhu, Z.; Liang, F.; Zhou, Z.; Zeng, X.; Wang, D.; Dong, P.; Zhao, J.; Sun, S.; Zhang, Y.; Li, X. Expanded biomass-derived hard carbon with ultra-stable performance in sodium-ion batteries. J. Mater. Chem. A 2018, 6, 1513-1522. (43)Zheng, T.; Xing, W.; Dahn, J. R. Carbons prepared from coals for anodes of lithium-ion cells. Carbon 1996, 34, 1501-1507. (44)Li, Y.; Hu, Y.-S.; Qi, X.; Rong, X.; Li, H.; Huang, X.; Chen, L. Advanced sodium-ion batteries using superior low cost pyrolyzed anthracite anode: towards practical applications. Energy Storage materials 2016, 5, 191-197. (45)Hatcher, P. G. Chemical structural models for coalified wood (vitrinite) in low rank coal. Org. Geochemistry 1990, 16, 959-968. (46) Shinn, J. H. From coal to single-stage and two-stage products: A reactive model of coal structure. Fuel 1984, 63, 1187-1196. (47)Ferrari, A. C.; Robertson, J. Raman spectroscopy of amorphous, nanostructured, diamond-like carbon, and nanodiamond. Philos. Trans. R. Soc., A 2004, 362, 2477-2512. (48) Ferrari, A. C.; Robertson, J. Interpretation of Raman spectra of disordered and amorphous carbon. Phys. Rev. B 2000, 61, 14095-14107. (49)Qiu, S.; Xiao, L.; Sushko, M. L.; Han, K. S.; Shao, Y.; Yan, M.; Liang, X.; Mai, L.; Feng, J.; Cao, Y.; Ai, X.; Yang, H.; Liu, J. Manipulating Adsorption–Insertion

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Page 25 of 26 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


Mechanisms in Nanostructured Carbon Materials for High-Efficiency Sodium Ion Storage. Adv. Energy Mater. 2017, 7, 1700403. (50) Bommier, C.; Surta, T. W.; Dolgos, M.; Ji, X. New Mechanistic Insights on Na-Ion Storage in Nongraphitizable Carbon. Nano Lett. 2015, 15, 5888-5892. (51) Cao, Y. L.; Xiao, L. F.; Ai, X. P.; Yang, H. X. Surface-modified graphite as an improved intercalating anode for lithium-ion batteries. Electrochem. Solid-State Lett. 2003, 6, A30-A33. (52) Wang, L. S.; Huang, Y. D.; Jia, D. Z. Triethyl orthoformate as a new film-forming electrolytes solvent for lithium-ion batteries with graphite anodes. Electrochim. Acta 2006, 51, 4950-4955. (53) Li, Z. F.; Jian, Z. L.; Wang, X. F.; Rodriguez-Perez, I. A.; Bommier, C.; Ji, X. L. Hard carbon anodes of sodium-ion batteries: undervalued rate capability. Chem. Commun. 2017, 53, 2610-2613. (54) Hasegawa, G.; Kanamori, K.; Kannari, N.; Ozaki, J.; Nakanishi, K.; Abe, T. Hard Carbon Anodes for Na-Ion Batteries: Toward a Practical Use. Chemelectrochem 2015, 2, 1917-1920. (55)Dahbi, M.; Nakano, T.; Yabuuchi, N.; Ishikawa, T.; Kubota, K.; Fukunishi, M.; Shibahara, S.; Son, J. Y.; Cui, Y. T.; Oji, H.; Komaba, S. Sodium carboxymethyl cellulose as a potential binder for hard-carbon negative electrodes in sodium-ion batteries. Electrochem. Commun. 2014, 44, 66-69. (56)Ponrouch, A.; Dedryvère, R.; Monti, D.; Demet, A. E.; Ateba Mba, J. M.; Croguennec, L.; Masquelier, C.; Johansson, P.; Palacín, M. R. Towards high energy

25



Page 26 of 26

density sodium ion batteries through electrolyte optimization. Energy Environ. Sci. 2013, 6, 2361-2369. (57)Pan, Y.; Zhang, Y.; Parimalam, B. S.; Nguyen, C. C.; Wang, G.; Lucht, B. L. Investigation of the solid electrolyte interphase on hard carbon electrode for sodium ion batteries. J. Electroanal. Chem. 2017, 799, 181-186. (58)Xiao, B.; Soto, F. A.; Gu, M.; Han, K. S.; Song, J.; Wang, H.; Engelhard, M. H.; Murugesan, V.; Mueller, K. T.; Reed, D.; Sprenkle, V. L.; Balbuena, P. B.; Li, X. Lithium-Pretreated Hard Carbon as High-Performance Sodium-Ion Battery Anodes. Adv. Energy Mater. 2018, 8, 1801441.

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