1T-MoS2 Nanoarray Electrode

Subscriber access provided by READING UNIV

Letter

Rationally Design Hierarchical SnO2/1T-MoS2 Nanoarray Electrode for Ultralong-life Li-S Batteries Maoxu Wang, Lishuang Fan, Da Tian, Xian Wu, Yue Qiu, Chenyang Zhao, Bin Guan, Yan Wang, Naiqing Zhang, and Kening Sun ACS Energy Lett., Just Accepted Manuscript • DOI: 10.1021/acsenergylett.8b00856 • Publication Date (Web): 14 Jun 2018 Downloaded from http://pubs.acs.org on June 16, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 25 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

ACS Energy Letters

Rationally Design Hierarchical SnO2/1T-MoS2 Nanoarray Electrode for Ultralong-life Li-S Batteries Maoxu Wang, † Lishuang Fan, †Da Tian, † Xian Wu, † Yue Qiu, † Chenyang Zhao, † Bin Guan, † Yan Wang, † Naiqing Zhang*,†,‡ and Kening Sun*,†,‡ †

State Key Laboratory of Urban Water Resource and Environment, School of Chemistry

and Chemical Engineering, Harbin Institute of Technology, Harbin, 150001 (China) ‡

Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of

Technology, Harbin, 150001 (China) *Corresponding Author Naiqing Zhang ([email protected]) Academy of Fundamental and Interdisciplinary Sciences, Harbin Institute of Technology, Harbin, China Tel: +451 86412153

Fax: +86-451-86412153

1

ACS Paragon Plus Environment

ACS Energy Letters 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

ABSTRACT: Serious shuttle effect of soluble polysulfides inevitably lead to low sulfur utilization and faster capacity decay, thus preventing the development of Li-S batteries. Array electrode has attracted much attention owing to their binder free and freestanding features. However, the insufficient surface area, lacking active sites with polysulfides and poor conductive nature of the array electrode could not satisfy the need for high-rate and long-life Li-S batteries, especially for the high sulfur loading of Li-S batteries. Thus, in this paper, we constructed the hierarchical C@SnO2/1T-MoS2 (C@SnO2@TMS) array electrode as the sulfur host. The hierarchical C@SnO2@TMS demonstrated strong adsorption with polysulfides, and which could effectively facilitate polysulfides redox kinetics. With the C@SnO2@TMS/S as the electrode, the batteries achieved superb C-rate properties, high specific capacity and ultra-long lifespan. Even undergo 4000 cycles at 5 C, the battery could retain a high specific capacity of 448 mAh g-1 with the capacity decay as low as 0.009% per cycle.

TOC GRAPHICS

2


Page 2 of 25

Page 3 of 25 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

ACS Energy Letters

Li-S batteries have attracted many attention owing to their high energy density (2800 Wh kg-1) and promising theoretical capacity (1675 mAh g-1).1 Unfortunately, there still exist some challenges, such as insulation nature of sulfur, severe shuttle effect of polysulfides and serious volume expansion of sulfur during redox process, inevitably limiting the practical application of Li-S batteries.2-6 Carbonaceous materials have been firstly developed to solve aforementioned problems because of their high conductivity and abundant specific surface area.7-9 For example, with mesoporous carbon,10-12 graphene4, 13, 14 and carbon nanofibers5, 15 as the sulfur host, the batteries showed increased capacity compared with pure sulfur as the cathode. However, the intrinsic nonpolar nature of carbon, causing them could not effectively tackle polar polysulfides only relying on the weak physical adsorption with polysulfides.16-22 Recently, some polar materials have been investigated to suppress the shuttle effect of polysulfides, such as TiO2,23, 24 Co3O4,25, TiO,26 and MnO25, 22, owing to their strong chemisorption with polysulfides. Nevertheless, traditional coating electrode is composed of sulfur cathode, addition of insulated binders and extra additives, thus causing poor three-dimensional conductive network structure for the transport of electron. Compared with traditional coating electrodes, the array electrode means that the active materials grow on the conductive substrate. Thereby, which could directly serve as electrode without extra binder and conductive addition, causing high contents of active materials, benefiting to realize high energy density of Li-S batteries. However, metal oxide nanoarray was lack of sufficient surface area and intrinsic electron transfer 3



ability, inevitably leading to poor rate performance in high sulfur loading.27 Hence, it’s imperative to rationally design array electrode structure to realize high energy density and excellent rate performance simultaneously for Li-S batteries. Hierarchical structure is composed of multilayered structure and complex components, which is believed to be capable to demonstrate large specific surface area, abundant active sites and adjustable components. Therefore, it has been applied in electrocatalysis devices,28, 29 energy storage devices,30, 31 drug delivery32 and senor technology33, etc. However, to our best knowledge, the hierarchical array electrodes haven’t been reported in Li-S batteries. Consequently, it’s urgent to seek for suitable components and rationally design hierarchical array electrode structure to fully take advantage of the merits of each composite components in the cathode of Li-S batteries. Hence, we designed and constructed hierarchical SnO2@1T-MoS2 nanoarray on carbon cloth (C@SnO2@TMS) as sulfur cathode for Li-S batteries. In this unique material architecture, each component synergistically serves as a specific purpose: On the one hand, porous SnO2 nanosheet could confine more sulfur within its nanoscale pores and provide more active sites to form strong chemisorption with the dissolvable polysulfides; Furthermore, the large pores between SnO2 nanosheets could effectively suppress the volume expansion of sulfur during the lithiation process, and allow for the easy penetration of electrolyte and fast transportation of Li+. On the other hand, the high conductivity of 1T-MoS2 nanosheet can expose abundant edge sites and enable fast electron transport, thus accelerating the polysulfides redox kinetic effectively. As the result, with the C@SnO2@TMS/S as the cathode materials, the batteries deliver high 4


Page 4 of 25

Page 5 of 25 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

ACS Energy Letters

specific capacities, superb cycle stability and excellent C-rate properties. Even undergo ultra-long 4000 cycles at 5 C, it could retain a capacity decay as low as 0.009% per cycle. The synthetic procedure was visualized in Illustration 1. Firstly, the SnS2 nanoarray precursor was prepared via one-step hydrothermal method. Then, to obtain the porous SnO2 nanosheet, the SnS2 precursor was subsequently annealed in air for 4h. NaBH4 was used as the reducing agent in the subsequent hydrothermal process, during which the 1T-MoS2 nanosheet was generated on the surface of porous SnO2 nanoarray. The as-prepared SnS2 precursor nanosheet had a uniform size and grown in the carbon nanofibers evenly, which could be observed in Figure 1a and Figure S1. After annealing at 500 °C for 4 h in air, the derived SnO2 showed obvious porous structure and similar array structure with its precursor (Figure 1b and Figure S2). By treating with further hydrothermal process, the generated 1T-MoS2 ultrathin nanosheets were

Illustration 1. Schematic illustration of the synthetic process of hierarchical C@SnO2/TMS nanoarray.

uniformly and tightly coated on the surface of porous SnO2 nanosheets (Figure 1c, d and Figure S3). In addition, the Scanning Electron Microscope (SEM) images of C@1T-MoS2 nanosheets were showed in Figure S4. 5



Figure 1. SEM images of a) C@SnS2, b) C@SnO2, c, d) C@SnO2/TMS.

Transmission Electron Microscope (TEM) was used to observe the more subtle structure of SnO2/TMS. As shown in Figure 2a and Figure S3, the SnO2 nanosheet was consist of nanoparticles-shape SnO2, and the 1T-MoS2 was tightly coated on the surface of SnO2 nanoparticles. The crystal structure of SnO2/TMS could be clearly verified in the high-resolution TEM picture of Figure 2b.34-36 The Energy-dispersive X-ray (EDX) analysis was shown in Figure 2c-g, the results imply that the S, O, Mo and Sn were dispersed uniformly in the SnO2/TMS sample, in agreement with the EDS mapping result (Figure S5). In addition, the N2 isothermal adsorption and desorption measurement was carried out to investigate the specific surface area of SnO2/TMS. As shown in Figure S6, the hierarchical SnO2/TMS demonstrated a high specific surface 6


Page 6 of 25

Page 7 of 25 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

ACS Energy Letters

area of 108.7 m2 g-1, which was much higher than SnO2 (69.5 m2 g-1) and 1T-MoS2 (29.2 m2 g-1).

Figure 2. a) TEM image, b) HRTEM image, c) TEM image, d) EDX elemental mapping of SnO2/TMS. d) S element; e) O element; f) Mo element; g) Sn element.

The X-ray photoelectron spectroscopy (XPS) was utilized to study the chemical compositions as well as the binding states of the elements in the C@SnO2/TMS sample. Figure 3a was the survey XPS spectrum of C@SnO2/TMS, which indicated the presence of Sn, O, S, Mo and C elements. The high-resolution Mo 3d spectrum was shown in Figure 3b, from which it can be observed that the components from the 2H phase at a binding energy that is about 0.9 eV higher than their 1T counterparts.37-40 In addition, the two characteristic peaks of Sn 3d can be identified in C@SnO2/TMS and 7



C@SnO2 samples (Figure 3c). However, the peaks of Sn 3d in the C@SnO2/TMS sample shifted to low binding energy region compared with the C@SnO2 sample, which indicated there formed strong electron interaction between the SnO2 nanosheet and 1TMoS2 nanosheet. The X-Ray Powder Diffraction (XRD) patterns of C@SnO2/TMS, C@SnO2 and C@1T-MoS2 were shown in Figure 3d. The diffraction peak at around 10° in C@SnO2/TMS and C@1T-MoS2 samples could be ascribed to the (002) plane of the metallic MoS2.38, 39 Furthermore, the characteristics peaks of SnO2 can be clearly identified in C@SnO2/TMS sample. The XRD pattern of C@SnS2 precursor was demonstrated in Figure S7. In addition, the weight ratio of C, SnO2 and 1T-MoS2 in the C@SnO2/TMS sample is about 69.5%, 20.8% and 9.7%, respectively according the thermogravimetric (TG) curve and XPS result. (Figure S8 and Table S1).

8


Page 8 of 25

Page 9 of 25 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

ACS Energy Letters

Figure 3. a) The survey XPS spectrum of C@SnO2/TMS. b) High-resolution X-ray photoelectron spectrum from the Mo 3d region. c), High-resolution X-ray photoelectron spectrum from the Sn 3d region. d) XRD pattern of C@SnO2/TMS compared with C@SnO2 and C@1T-MoS2.

The binding energy of Li2S4 with SnO2 and 1T-MoS2, as well as binding geometric models based on density functional theory (DFT) were shown in Figure 4a, b. The binding energy of Li2S4 with SnO2 (2.64 eV) is higher than 1T-MoS2 (0.46 eV), indicating the stronger adsorption with polysulfides of SnO2. In order to intuitively observe the adsorb ability of C@SnO2/TMS materials, the Li2Sx solution was fabricated by

dissolving

into

a

hybrid

solution

with

9


0.1

mol/L

lithium

bis


(trifluoromethanesulfonyl)

imide

(LiTFSI)

and

Page 10 of 25

the

volume

ratio

of

1:1

dimethoxymethane (DME) and 1,3-dioxolane (DOL) to form a deep yellow solution.41, 42

In addition, the more clear color means the stronger adsorption capability of anchor

materials.43-45 And the corresponding UV-vis curves of the Li2Sx solution exposed to different anchor materials were investigated to provide more accurate information for the adsorb capability. As shown in Figure 4a, compared with nonpolar carbon cloth, the three polar materials showed stronger adsorption with Li2Sx. Furthermore, by comparison with C@1T-MoS2, the C@SnO2 demonstrated the stronger adsorption capability according to the UV-vis results, which in agreement with the DFT results. (Figure 4a, b). Of note is that, the C@SnO2/TMS even showed stronger adsorb capability than C@SnO2, which could be estimated to be the increased surface area and synergistic effect of C@SnO2/TMS materials.

Figure 4. Atomic conformations and binding energy for Li2S4 species adsorption on a) SnO2 and b) 1T-MoS2. c) UV-vis spectra and associated color changes of the Li2Sx solution exposure to C@SnO2/TMS, C@SnO2, C@1T-MoS2 and Carbon cloth materials for 6 h.

The diffusion barriers of Li ion on the surface of SnO2 and 1T-MoS2 were validated by using CI-NEB calculations to verify the catalytic capability of propelling the polysulfides redox process. The Li ion diffusion barriers profiles as well as diffusion 10


Page 11 of 25 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

ACS Energy Letters

pathways were shown in Figure 5a, b. According to the results of Li ion diffusion barriers profiles, the 1T-MoS2 showed lower barrier, thus reflecting the stronger catalytic capability compared with SnO2. To provide further understanding of catalytic effect in Li-S batteries, the widely used CV measurement was firstly investigated.46 As shown in Figure 5c, the CV profile of C@SnO2/TMS/S electrode exhibited two reduction peaks at about 2.32 V and 2.05 V, corresponding to the reduction process of S82-→S62-→S42- and S42-→S22-→Li2S, respectively.47 And the oxidation peak at 2.5 V can be ascribed to the complex oxidation process of Li2S→S.48 In addition, the peak separation between the oxidation peak and the reduction peak at low potential is used usually to evaluate the electrochemical polarization of electrode materials.19, 49, 50 As we can see from the Figure 5c, the C@SnO2/TMS/S electrode showed the smallest electrochemical polarization compared with C@SnO2/S electrode and C@1T-MoS2/S electrode materials. To further reveal the reduced electrochemical polarization, the charge-discharge profiles of C@SnO2/TMS/S, C@SnO2/S and C@1T-MoS2/S were presented in Figure 5d. The ƞ represents the polarization potential between the second discharge plateau and the charge plateau. The results showed that the C@SnO2/TMS/S electrode display the smallest polarization potential (ƞ1=0.15 V) compared with C@1TMoS2/S (ƞ2=0.20 V) and C@SnO2/S electrodes (ƞ3=0.22 V), which agree with the results of CV profiles. The reduced electrochemical polarization reflects the excellent catalytic capability of C@SnO2/TMS. By contrast, the broad cathodic and anodic peaks coupled with large ƞ (0.25) confirmed form CV profile and charge-discharge profile of C/S reflecting that the C/S electrode show the most severe polarization among the four 11



different sulfur host materials (Figure S9). To further evaluate the catalytic ability of three different anchor materials, the initial activation energy barrier of Li2S on various electrode materials was investigated and the initial charging voltage profiles are shown in Figure 5e. Of note, the charge voltage plateaus after the short jump on behalf of the phase conversion reaction from Li2S to S.51 As we can see, the C@SnO2/S displayed the highest potential barrier and the C@SnO2/TMS/S showed the lowest charging barrier. In the Figure 5f, the discharge capacities (QH and QL) of three different electrodes are studied. As expected, the C@SnO2/TMS/S delivered the highest QH and QL compared with C@SnO2/S and C@1T-MoS2/S electrodes. Notable, confirmed with reduced electrochemical polarization, lowed Li2S activation energy barrier and increased plateau capacities, the C@SnO2/TMS showed the more excellent catalytic capability than 1T-MoS2, which could be ascribed to the unique materials architecture and synergistic effect of composites.

Figure 5. a) Diffusion pathways and b) Li ion diffusion barriers profiles on SnO2 and 1T-MoS2. 12


Page 12 of 25

Page 13 of 25 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

ACS Energy Letters

c) The CV profiles recorded at 0.1 mV s-1 from 1.7 V to 2.8 V. d) Representative charge– discharge voltage profiles at 0.2 C. e) First cycle charge voltage profiles of C@SnO2/TMS/S, C@SnO2/S and C@1T-MoS2/S electrodes. f) The discharge capacity of two plateau QH and QL. Different host materials of 1) C@SnO2/TMS/S, 2) C@SnO2/S and 3) C@1T-MoS2/S are utilized.

To assess the electrochemical performance of C@SnO2/TMS/S, the rate performance was firstly performed from 0.2 C to 5 C (Figure 6a). The C@SnO2/TMS/S delivered a high specific capacity of 1500 mAh g-1 at 0.2 C, and the battery showed 1300, 1180, 1050 and 860 mAh g-1 at current densities of 0.5 C, 1 C, 2 C and 5 C, respectively, which is much higher than C@SnO2/S and C@1T-MoS2/S, especially at high current densities. In addition, when the current density skipped back to 0.2 C, almost all of the capacity in the beginning is recovered. In contrast, when the carbon cloth as the sulfur host material, the battery showed diminished capacity and worse rate performance (Figure S10). Furthermore, the C@SnO2/TMS as the electrode for Li-ion batteries in the Li-S system demonstrated 25 mAh g-1 at 0.2 C, which only accounts for the 1.7% of specific capacity of C@SnO2/TMS/S (Figure S11). Besides the high specific capacities and excellent rate performance, the cycle performance of three different electrodes with a sulfur loading 2.75 mg cm-2 at 0.5 C were demonstrated in Figure 6b. As shown in the Figure 6b, the C@SnO2/TMS/S showed the initial capacity of 1261 mAh g-1, which is far much higher than C@SnO2/S (1058 mAh g-1) and C@1TMoS2/S (921 mAh g-1). Even after 200 cycles, the specific capacity higher than 1175 mAh g-1 was obtained with a capacity retention as high as 93.1%, which was still batter 13



than C@SnO2/S (82.9%) and C@1T-MoS2/S (67.5%). When the sulfur loading increase to 5.0 mg cm-2, the C@SnO2/TMS/S was first activated at 0.05 C and then it demonstrated an outstanding initial capacity of 911 mAh g-1 and could retain a high specific capacity 800 mAh g-1 at 0.2C (Figure 6c). And the areal capacity of C@SnO2/TMS/S can obtain 4.0 mAh cm-2 after 200 cycles at 0.2 C, which is close to the value of state-of-art commercial cathode materials of Li-ion batteries. To satisfy the commercial demand for quick-charge energy storage devices, the special charge-discharge model was carried out. As shown in Figure 6d, when galvanostatic charged at 2 C and galvanostatic discharged at 0.5 C, the battery showed a

high initial specific capacity of 1200 mAh g-1 as well as retained 89% initial capacity after 100 cycles. In addition, the ultralong-term cycling performance of C@SnO2/TMS/S was performed (Figure 6e). The C@SnO2/TMS/S material showed excellent initial specific capacity of 710 mAh g-1 and 448 mAh g-1 could be retained after 4000 cycles at 5 C with a capacity decay as low as 0.009% per cycle, which improved the cyclic stability by one to two orders of magnitude compared with previously reported works (Table S2). As the results, the C@SnO2/TMS/S electrode demonstrated higher specific capacity and better cycling stability, which could attribute to the strong chemisorption, excellent catalytic ability and unique structure of hierarchical C@SnO2/TMS nanoarray electrode.

14


Page 14 of 25

Page 15 of 25 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

ACS Energy Letters

Figure 6. a) Rate performance. b) Cycling at 0.5 C over 200 cycles of C@1T-MoS2/S, C@SnO2/S and C@SnO2/TMS/S composites with sulfur loading of 2.75 mg cm-2. c) The cycle performance of C@SnO2/TMS/S with a high sulfur loading of 5.0 mg cm-2. d) The quick galvanostatic charging at 2 C and galvanostatic discharging at 0.5 C. e) Long-term cycling stability test showing a high capacity retention over 4000 cycles at 5 C for C@SnO2/TMS/S composites.

The electrochemical impedance spectrum (EIS) is a usual crucial method to determine the performance of Li-S batteries, which is composed of one semicircle in high frequency and one oblique line in low frequency.52-54 And the ESI semicircle and oblique line can be ascribed to charge transfer resistance and diffusion resistance, respectively. According to the results of Figure 7, the C@SnO2/TMS/S showed the smallest ESI semicircle diameter, thus indicating the highly improved charge transfer capability compared to C@SnO2/S and C@1T-MoS2/S. So the batteries with C@SnO2/TMS/S as the cathode could exhibit excellent rate performance. The photograph images of the separators of C/S, C@1T-MoS2/S, C@SnO2/S and 15



C@SnO2/TMS/S electrodes after 200 discharge cycles were observed to check the capability of trapping effect of polysulfides. As shown in Figure S12, the separator with C/S electrode showed pale yellow color owing to the deposition of electrode, while the separator for C@SnO2/TMS/S electrode showed almost no changed color compared with separators of C/S, C@SnO2/S and C@1T-MoS2/S, thus indicating the superb trapping effect for polysulfides of C@SnO2/TMS.

Figure 7. Electrochemical impedance spectra of C@SnO2/TMS/S compared with C@SnO2/S and C@1T-MoS2/S.

In summary, we have designed and fabricated hierarchical C@SnO2/TMS array electrode as sulfur host. The unique structure C@SnO2/TMS demonstrates advantages as follows: strong chemisorption, reduced electrochemical polarization, lower Li2S charging barrier and enhanced charge transfer capability. Hence, with the C@SnO2/TMS as the sulfur host, the battery demonstrated high specific capacity, excellent rate performance and stable cycle life. Especially, when cycled at 5 C for ultra-long 4000 cycles, the C@SnO2/TMS/S showed a capacity decay as low as 0.009% per cycle. The remarkable electrochemical performance confirmed that this work can 16


Page 16 of 25

Page 17 of 25 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

ACS Energy Letters

provide a new idea to rationally design electrode structure for enhancing the electrochemical performance of Li-S batteries. And this work may push the development of high-performance Li-S batteries by utilizing hierarchical structure composites.

Supporting Information. The Supporting Information is available free of charge he following files are available free of charge. Experimental details, structure characterization, and electrochemical properties of C@SnO2/TMS + based electrode, along with additional supporting data (PDF) AUTHOR INFORMATION Corresponding Author *E-mail: [email protected] (Naiqing Zhang). Notes The authors declare no competing financial interest. ACKNOWLEDGMENT This work was supported by the National Natural Science Foundation of China (no. 21646012), the State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (no. 2016DX08) and China Postdoctoral Science Foundation (no. 2016M600253). ABBREVIATIONS Li-S, Lithium–sulfur; C, carbon nanofibers; SnO2@1T-MoS2, SnO2@TMS; QH, upperplateau discharge capacities; QL, lower plateau discharge capacities.

17



References (1) Bruce, P. G.; Freunberger, S. A.; Hardwick, L. J.; Tarascon, J. M. Li-O2 and Li-S Batteries With High Energy Storage. Nat. Mater. 2011, 11, 19-29. (2)

Zhou, W.; Yu, Y.; Chen, H.; DiSalvo, F. J.; Abruna, H. D. Yolk-Shell

Structure of Polyaniline-Coated Sulfur For Lithium-Sulfur Batteries. J. Am. Chem. Soc. 2013, 135, 16736-16743. (3)

Qie, L.; Manthiram, A. A Facile Layer-By-Layer Approach for High-

Areal-Capacity Sulfur Cathodes. Adv. Mater. 2015, 27, 1694-1700. (4)

Zhou, G.; Pei, S.; Li, L.; Wang, D. W.; Wang, S.; Huang, K.; Yin, L. C.;

Li, F.; Cheng, H. M. A Graphene-Pure-Sulfur Sandwich Structure for Ultrafast, Long-Life Lithium-Sulfur Batteries. Adv. Mater. 2014, 26, 625-631. (5)

Xu, H.; Qie, L.; Manthiram, A. An Integrally-Designed, Flexible

Polysulfide Host for High-Performance Lithium-Sulfur Batteries with Stabilized Lithium-Metal Anode. Nano Energy 2016, 26, 224-232. (6)

Liang, J.; Jiao, Y.; Jaroniec, M.; Qiao, S. Z. Sulfur and Nitrogen Dual-

Doped Mesoporous Graphene Electrocatalyst for Oxygen Reduction with Synergistically Enhanced Performance. Angew. Chem. Int. Ed. 2012, 51, 1149611500. (7)

Zhou, G.; Zhao, Y.; Manthiram, A. Dual-Confined Flexible Sulfur

Cathodes Encapsulated in Nitrogen-Doped Double-Shelled Hollow Carbon Spheres and Wrapped with Graphene for Li-S Batteries. Adv. Energy Mater. 2015, 5, 1402263. (8)

Fang, R.; Zhao, S.; Hou, P.; Cheng, M.; Wang, S.; Cheng, H. M.; Liu, C.; 18


Page 18 of 25

Page 19 of 25 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

ACS Energy Letters

Li, F. 3D Interconnected Electrode Materials with Ultrahigh Areal Sulfur Loading for Li-S Batteries. Adv. Mater. 2016, 28, 3374-3382. (9)

Hu, C.; Kirk, C.; Cai, Q.; Cuadrado-Collados, C.; Silvestre-Albero, J.;

Rodríguez-Reinoso, F.; Biggs, M. J. A High-Volumetric-Capacity Cathode Based on Interconnected Close-Packed N-Doped Porous Carbon Nanospheres for LongLife Lithium-Sulfur Batteries. Adv. Energy Mater. 2017, 1701082. (10) Chung, S. H.; Manthiram, A. A Polyethylene Glycol-Supported Microporous Carbon Coating as A Polysulfide Trap for Utilizing Pure Sulfur Cathodes in Lithium-Sulfur Batteries. Adv. Mater. 2014, 26, 7352-7357. (11) Balach, J.; Jaumann, T.; Klose, M.; Oswald, S.; Eckert, J.; Giebeler, L. Functional Mesoporous Carbon-Coated Separator for Long-Life, High-Energy Lithium-Sulfur Batteries. Adv. Funct. Mater. 2015, 25, 5285-5291. (12) Li, Z.; Wu, H. B.; Lou, X. W. Rational Designs and Engineering of Hollow Micro-/Nanostructures as Sulfur Hosts for Advanced Lithium–Sulfur Batteries. Energy Environ. Sci. 2016, 9, 3061-3070. (13) Zhang, Z.; Kong, L.-L.; Liu, S.; Li, G.-R.; Gao, X.-P. A High-Efficiency Sulfur/Carbon Composite Based on 3D Graphene Nanosheet@Carbon Nanotube Matrix as Cathode for Lithium-Sulfur Battery. Adv. Energy Mater. 2017, 7, 1602543. (14) Wang, D.-W.; Li, F.; Liu, M.; Lu, G. Q.; Cheng, H.-M. 3D Aperiodic Hierarchical Porous Graphitic Carbon Material for High-Rate Electrochemical Capacitive Energy Storage. Angew. Chem. Int. Ed. 2008, 120, 379-382. (15) Wu, F.; Zhao, E.; Gordon, D.; Xiao, Y.; Hu, C.; Yushin, G. Infiltrated Porous Polymer Sheets as Free-Standing Flexible Lithium-Sulfur Battery 19



Electrodes. Adv. Mater. 2016, 28, 6365-6371. (16) Hwang, J.-Y.; Kim, H. M.; Shin, S.; Sun, Y.-K. Designing a HighPerformance Lithium-Sulfur Batteries Based on Layered Double HydroxidesCarbon Nanotubes Composite Cathode and a Dual-Functional GraphenePolypropylene-Al2O3 Separator. Adv. Funct. Mater. 2017, 1704294. (17) Xu, G.; Yan, Q.; Wang, S.; Kushima, A.; Bai, P.; Liu, K.; Zhang, X.; Tang, Z.; Li, J. A Thin Multifunctional Coating on a Separator Improves the Cyclability and Safety of Lithium Sulfur Batteries. Chem, Sci. 2017, 8, 6619-6625. (18) Liang, X.; Hart, C.; Pang, Q.; Garsuch, A.; Weiss, T.; Nazar, L. F. A Highly Efficient Polysulfide Mediator for Lithium-Sulfur Batteries. Nat. Commun. 2015, 6, 5682. (19) Sun, F.; Wang, J.; Long, D.; Qiao, W.; Ling, L.; Lv, C.; Cai, R. A HighRate Lithium–Sulfur Battery Assisted by Nitrogen-Enriched Mesoporous Carbons Decorated with Ultrafine La2O3 Nanoparticles. J. Mater. Chem. A 2013, 1, 13283. (20) Liang, J.; Yin, L.; Tang, X.; Yang, H.; Yan, W.; Song, L.; Cheng, H. M.; Li, F. Kinetically Enhanced Electrochemical Redox of Polysulfides on Polymeric Carbon Nitrides for Improved Lithium-Sulfur Batteries. ACS Appl. Mater. interfaces 2016, 8, 25193-25201. (21) Yang, Y.; Wang, Z.; Li, G.; Jiang, T.; Tong, Y.; Yue, X.; Zhang, J.; Mao, Z.; Sun, W.; Sun, K. Inspired by the “Tip Effect”: A Novel Structural Design Strategy for the Cathode in Advanced Lithium–Sulfur Batteries. J. Mater. Chem. A 2017, 5, 3140-3144. (22) Li, Z.; Zhang, J.; Lou, X. W. Hollow Carbon Nanofibers Filled with MnO2 20


Page 20 of 25

Page 21 of 25 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

ACS Energy Letters

Nanosheets as Efficient Sulfur Hosts for Lithium-Sulfur Batteries. Angew. Chem. Int. Ed. 2015, 54, 12886-12890. (23) Zhou, G.; Zhao, Y.; Zu, C.; Manthiram, A. Free-Standing TiO2 NanowireEmbedded Graphene Hybrid Membrane for Advanced Li/Dissolved Polysulfide Batteries. Nano Energy 2015, 12, 240-249. (24) Lei, T.; Xie, Y.; Wang, X.; Miao, S.; Xiong, J.; Yan, C. TiO2 Feather Duster as Effective Polysulfides Restrictor for Enhanced Electrochemical Kinetics in Lithium-Sulfur Batteries. Small 2017, 13, 1701013. (25) Chang, Z.; Dou, H.; Ding, B.; Wang, J.; Wang, Y.; Hao, X.; MacFarlane, D. R. Co3O4 Nanoneedle Arrays as a Multifunctional “Super-Reservoir” Electrode for Long Cycle Life Li–S Batteries. J. Mater. Chem. A 2017, 5, 250-257. (26) Li, Z.; Guan, B. Y.; Zhang, J.; Lou, X. W. A Compact Nanoconfined Sulfur Cathode for High-Performance Lithium-Sulfur Batteries. Joule 2017, 1, 576-587. (27) Peng, H. J.; Huang, J. Q.; Zhang, Q. A Review of Flexible Lithium-Sulfur and Analogous Alkali Metal-Chalcogen Rechargeable Batteries. Chem. Soc. Rev. 2017, 46, 5237-5288. (28) Yu, M.; Zhao, S.; Feng, H.; Hu, L.; Zhang, X.; Zeng, Y.; Tong, Y.; Lu, X. Engineering Thin MoS2 Nanosheets on TiN Nanorods: Advanced Electrochemical Capacitor Electrode and Hydrogen Evolution Electrocatalyst. ACS Energy Lett. 2017, 2, 1862-1868. (29) Amiinu, I. S.; Pu, Z.; Liu, X.; Owusu, K. A.; Monestel, H. G. R.; Boakye, F. O.; Zhang, H.; Mu, S. Multifunctional Mo-N/C@MoS2 Electrocatalysts for HER, OER, ORR, and Zn-Air Batteries. Adv. Funct. Mater. 2017, 27, 1702300. 21



(30) Wang, S.; Guan, B. Y.; Yu, L.; Lou, X. W. D., Rational Design of ThreeLayered TiO2@Carbon@MoS2 Hierarchical Nanotubes for Enhanced Lithium Storage. Adv. Mater. 2017, 29, 1702724. (31) Zhu, J.; Tang, S.; Wu, J.; Shi, X.; Zhu, B.; Meng, X. Wearable HighPerformance Supercapacitors Based on Silver-Sputtered Textiles with FeCo2S4NiCo2S4 Composite Nanotube-Built Multitripod Architectures as Advanced Flexible Electrodes. Adv. Energy Mater. 2017, 7, 1601234. (32) Wu, J.; Chen, A.; Qin, M.; Huang, R.; Zhang, G.; Xue, B.; Wei, J.; Li, Y.; Cao, Y.; Wang, W. Hierarchical Construction of A Mechanically Stable Peptide– Graphene Oxide Hybrid Hydrogel for Drug Delivery and Pulsatile Triggered Release in Vivo. Nanoscale 2015, 7, 1655-1660. (33) Siva Prasad, M.; Chen, R.; Ni, H.; Kiran Kumar, K. Directly Grown of 3D-Nickel Oxide Nano Flowers on TiO2 Nanowire Arrays by Hydrothermal Route for Electrochemical Determination of Naringenin Flavonoid in Vegetable Samples. Arabian J. Chem. 2017, 12, 004. (34) Sun, Y.; Lei, F.; Gao, S.; Pan, B.; Zhou, J.; Xie, Y. Atomically Thin Tin Dioxide Sheets for Efficient Catalytic Oxidation of Carbon Monoxide. Angew. Chem. Int. Ed. 2013, 52, 10569-10572. (35) Wang, Q.; Wang, D.; Wu, M.; Liu, B.; Chen, J.; Wang, T.; Chen, J. Porous SnO2 Nanoflakes with Loose-Packed Structure: Morphology Conserved Transformation From SnS2 Precursor and Application in Lithium Ion Batteries and Gas Sensors. J. Phys. Chem. Solids 2011, 72, 630-636. (36) Wang, M.; Fan, L.; Wu, X.; Tian, D.; Cheng, J.; Qiu, Y.; Wu, H.; Guan, B.; 22


Page 22 of 25

Page 23 of 25 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

ACS Energy Letters

Zhang, N.; Sun, K.; et al. Hierarchical Mesoporous SnO2 Nanosheets on Carbon Cloth Toward Enhancing the Polysulfides Redox for Lithium–Sulfur Batteries. J. Mater. Chem. A 2017, 5, 19613-19618. (37) Wu, M.; Zhan, J.; Wu, K.; Li, Z.; Wang, L.; Geng, B.; Wang, L.; Pan, D. Metallic 1T MoS2 Nanosheet Arrays Vertically Grown on Activated Carbon Fiber Cloth for Enhanced Li-Ion Storage Performance. J. Mater. Chem. A 2017, 5, 1406114069. (38) Acerce, M.; Voiry, D.; Chhowalla, M. Metallic 1T Phase MoS2 Nanosheets as Supercapacitor Electrode Materials. Nat. Nanotechnol. 2015, 10, 313-318. (39) Geng, X.; Jiao, Y.; Han, Y.; Mukhopadhyay, A.; Yang, L.; Zhu, H. Freestanding Metallic 1T MoS2 with Dual Ion Diffusion Paths as High Rate Anode for Sodium-Ion Batteries. Adv. Funct. Mater. 2017, 27, 1702998. (40) Cai, L.; Cheng, W.; Yao, T.; Huang, Y.; Tang, F.; Liu, Q.; Liu, W.; Sun, Z.; Hu, F.; Jiang, Y.; et al. High-Content Metallic 1T Phase in MoS2-Based Electrocatalyst for Efficient Hydrogen Evolution. J. Phys. Chem. C 2017, 121, 15071-15077. (41) Patel, M. U.; Demir-Cakan, R.; Morcrette, M.; Tarascon, J. M.; Gaberscek, M.; Dominko, R. Li-S Battery Analyzed by UV/Vis in Operando Mode. ChemSusChem 2013, 6, 1177-1181. (42) Zou, Q.; Lu, Y.-C. Solvent-Dictated Lithium Sulfur Redox Reactions: An Operando UV–vis Spectroscopic Study. J. Phys. Chem. Lett. 2016, 7, 1518-1525. (43) Xu, J.; Zhang, W.; Chen, Y.; Fan, H.; Su, D.; Wang, G. MOF-Derived 23



Porous N–Co3O4@N–C Nanododecahedra Wrapped with Reduced Graphene Oxide as a High Capacity Cathode for Lithium–Sulfur Batteries. J. Mater. Chem. A 2018, 6, 2797-2807. (44) Lei, T.; Chen, W.; Huang, J.; Yan, C.; Sun, H.; Wang, C.; Zhang, W.; Li, Y.; Xiong, J. Multi-Functional Layered WS2 Nanosheets for Enhancing the Performance of Lithium-Sulfur Batteries. Adv. Energy Mater. 2017, 7, 1601843. (45) Babu, G.; Masurkar, N.; Al Salem, H.; Arava, L. M. Transition Metal Dichalcogenide Atomic Layers for Lithium Polysulfides Electrocatalysis. J. Am. Chem. Soc. 2017, 139, 171-178. (46) Xiao, Z.; Yang, Z.; Wang, L.; Nie, H.; Zhong, M.; Lai, Q.; Xu, X.; Zhang, L.; Huang, S. A Lightweight TiO2/Graphene Interlayer, Applied as a Highly Effective Polysulfide Absorbent for Fast, Long-Life Lithium-Sulfur Batteries. Adv. Mater. 2015, 27, 2891-2898. (47) Jeong, T.-G.; Choi, D. S.; Song, H.; Choi, J.; Park, S.-A.; Oh, S. H.; Kim, H.; Jung, Y.; Kim, Y.-T. Heterogeneous Catalysis for Lithium–Sulfur Batteries: Enhanced Rate Performance by Promoting Polysulfide Fragmentations. ACS Energy Lett. 2017, 2, 327-333. (48) Liu, D.; Zhang, C.; Zhou, G.; Lv, W.; Ling, G.; Zhi, L.; Yang, Q.-H. Catalytic Effects in Lithium-Sulfur Batteries: Promoted Sulfur Transformation and Reduced Shuttle Effect. Adv. Sci. 2017, 1700270. (49) Sun, Z.; Zhang, J.; Yin, L.; Hu, G.; Fang, R.; Cheng, H. M.; Li, F. Conductive Porous Vanadium Nitride/Graphene Composite as Chemical Anchor of Polysulfides for Lithium-Sulfur Batteries. Nat. Commun. 2017, 8, 14627. 24


Page 24 of 25

Page 25 of 25 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

ACS Energy Letters

(50) Faber, M. S.; Lukowski, M. A.; Ding, Q.; Kaiser, N. S.; Jin, S. EarthAbundant Metal Pyrites (FeS2, CoS2, NiS2, and Their Alloys) for Highly Efficient Hydrogen Evolution and Polysulfide Reduction Electrocatalysis. J. Phys. Chem. C. 2014, 118, 21347-21356. (51) Zhou, G.; Tian, H.; Jin, Y.; Tao, X.; Liu, B.; Zhang, R.; Seh, Z. W.; Zhuo, D.; Liu, Y.; Sun, J.; et al. Catalytic Oxidation of Li2S on the Surface of Metal Sulfides for Li-S Batteries. P. Natl. Acad. Sci. USA. 2017, 114, 840-845. (52) Gu, X.; Wang, Y.; Lai, C.; Qiu, J.; Li, S.; Hou, Y.; Martens, W.; Mahmood, N.; Zhang, S. Microporous Bamboo Biochar for Lithium-Sulfur Batteries. Nano Res. 2014, 8, 129-139. (53) Waluś, S.; Robba, A.; Bouchet, R.; Barchasz, C.; Alloin, F. Influence of the Binder and Preparation Process on the Positive Electrode Electrochemical Response and Li/S System Performances. Electrochim. Acta 2016, 210, 492-501. (54) Conder, J.; Villevieille, C.; Trabesinger, S.; Novák, P.; Gubler, L.; Bouchet, R. Electrochemical Impedance Spectroscopy of a Li–S Battery: Part 1. Influence of the Electrode and Electrolyte Compositions on the Impedance of Symmetric Cells. Electrochim. Acta 2017, 244, 61-68.

25


1T-MoS2 Nanoarray Electrode

Recommend Documents