Tantalum-Doped Titanium Oxide with Rutile Structure as a Novel

Subscriber access provided by Stockholm University Library

Letter

Tantalum-Doped Titanium Oxide with Rutile Structure as a Novel Anode Material for Sodium-Ion Battery Hiroyuki Usui, Yasuhiro Domi, Kunihiko Takama, Yuri Tanaka, and Hiroki Sakaguchi ACS Appl. Energy Mater., Just Accepted Manuscript • Publication Date (Web): 29 Apr 2019 Downloaded from http://pubs.acs.org on April 30, 2019

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 15 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 Applied Energy Materials

Tantalum-Doped

Titanium

Oxide

with

Rutile

Structure as a Novel Anode Material for Sodium-Ion Battery Hiroyuki Usui†,§, Yasuhiro Domi†,§, Kunihiko Takama†,§, Yuri Tanaka‡,§, and Hiroki Sakaguchi†,§,*

† Department

of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4-101 Minami, Koyama-cho, Tottori 680-8552, Japan

‡ Course

of Chemistry and Biotechnology, Department of Engineering, Graduate School of Sustainability Science, Tottori University, 4-101 Minami, Koyama-cho, Tottori 680-8552, Japan

§ Center

for Research on Green Sustainable Chemistry, Tottori University, 4-101 Minami, Koyama-cho, Tottori 680-8552, Japan

Corresponding Author Keywords:

* Tel./Fax: +81-857-31-5265, E-mail: [email protected]

Rutile TiO2; Ta doping; Na-ion battery; Anode material; Electron charge density

1 ACS Paragon Plus Environment

ACS Applied Energy Materials 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

Page 2 of 15

ABSTRACT

We hydrothermally synthesized various-element-doped rutile TiO2 for Na-ion battery anodes. Sn- and In-doped TiO2 electrodes showed poor performances. In contrast, Ta- and Nb-doped TiO2 electrodes exhibited larger discharge capacities, which is attributed to expanded diffusion path and improved electronic conductivity. Among them, the Ta-doped one delivered excellent cycling performance and better rate capability. A first principle calculation revealed that Ta doping reduced electron charge density in rutile’s Na+-diffusion path because Ta5+ has larger effective nuclear charge to attract strongly outermost electron. Therefore, Na+ was not bound by electron to easily diffuse in TiO2 particle, which leading to the enhanced capacity.


Page 3 of 15 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


1. INTRODUCTION Na-ion batteries (NIBs) have been recently considered as an attractive alternative to Li-ion batteries (LIBs) for large-sized rechargeable batteries because Na resource has a lower cost and a wider availability than Li resource. Na+ has a 2.4 times larger ionic volume than Li+, resulting in slower kinetics of its host materials of negative electrode (anodes) and positive electrodes (cathodes).1 A fundamental development of NIB requires a new material research for active material because electrochemical insertion-extraction properties of Na+ appear similar, but are in fact quite different from those of Li+. Titanium oxide-based materials are one of the promising candidates of anode materials emphasizing the long-term durability and the high safety. Since 2014, reversible Na-insertion/extraction reactions have been reported for anatase TiO2,2 TiO2(B),3 Na2Ti3O7,4 and Na2+xTi6O13.5,6 Among them, many researchers have intensively studied anatase-type TiO2 because it has a low cost, high availability, and relatively high electrochemical activity with Na+. By contrast, nobody has reported on rutile TiO2 until 2015 owing to its less activity originated from highly anisotropic Na+-diffusion along c-axis direction, which had been well known in research as LIB anode. Under such situation, the authors have revealed for the first time Na+-insertion/extraction of rutile TiO2 as shown in Figure 1(a).7 The authors have controlled particle size and crystallite size of rutile TiO2 by using a

G' synthesis and a subsequent annealing to clarify a significant size

effect. By increasing a ratio of the crystallite size to the particle size, one-dimensional Na+diffusion could enable Na storage in the inner part of TiO2 particle because it could reduce the density of grain boundary preventing Na+ diffusion.7,8 In addition to this, the authors have discovered the remarkable effect of Nb-doping for the first time. By Nb-doping into rutile TiO2, its anode performances were drastically improved.7-9 Two effects of the doping have been confirmed (Figure 1(b)). The first effect is significant enhancement of electronic conductivity: we have confirmed that the Nb-doped rutile TiO2 showed a three orders of magnitude higher conductivity compared with undoped one.7 When Nb is doped into anatase TiO2, 4d orbitals of Nb are strongly hybridized with 3d ones of Ti to form a d-nature conduction band.10,11 Thus, Nb-doped anatase was well studied as a transparent conductor material.10,11 It has been predicted that a doping into rutile TiO2 also improves an electronic conductivity by the generation of defect level in its



ACS Paragon Plus Environment

Page 4 of 15

Page 5 of 15 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


2. EXPERIMENTAL Impurity elements (Ta, Nb, Sn, and In)-doped TiO2 powders were synthesized by a hydrothermal method. The synthesis conditions were summarized in Figure S1. These TiO2 have a crystal structure of tetragonal rutile-type TiO2 (Inorganic Crystal Structure Database, ICSD No. 00-021-1276), which was confirmed by analysis using an X-ray diffraction (XRD, Ultima IV, Rigaku) as shown in Figure 2G :5 A single phase of rutile TiO2 could be formed for the doping amounts of 6.7 at.% Ta, 5.7 at.% Nb, 2.6 at.% Sn, and 0.5 at.% In. The doping amount was evaluated by the analysis using an energy-dispersive X-ray fluorescent (XRF) analyzer. The morphologies were observed by using a field emission scanning electron microscope (FE-SEM, JSM-6701F, JEOL Ltd.). Ta-doped TiO2 particles showed rectangular shape with size of about 170 nm, which is very similar to that of Nb-doped TiO2 (Figure S8). Electrodes were prepared by using of TiO2/acetylene black/carboxymethyl cellulose/styrene-butadiene rubber with the weight ratio of 70/15/10/5 wt.%. We prepared coin cells consisting of the TiO2 electrodes, Na metal sheets, and an electrolyte of 1.0 mol dmG; sodium bis(fluorosulfonyl)amide (NaFSA)-dissolved/PC. The ' G

' tests were performed in the potential range between 0.005 and 3.0 V vs. Na+/Na

at 303 K at 50 mA gG, (0.15 C). Other conditions were described in the previous paper.6,7,24 To discuss electron charge density and Na+ behavior in the diffusion path of doped rutile TiO2, a firstprinciple calculation was carried.

3. RESULTS AND DISCUSSION Figure 2 shows

' G

' curves of various impurity-element-doped rutile TiO2

electrodes in the initial three cycles. The all electrodes showed initial irreversible capacities: the Coulombic efficiencies at the first cycles were +1KG/-K5 The trigger of the irreversible capacities is possibly an electrolyte decomposition or a side reaction of hydroxyl groups on TiO2 surface. These efficiencies improved to 00KGH-K at the third cycle. The undoped TiO2 electrode exhibited gentle potential shoulders in charge (sodiation) and discharge (desodiation) reactions. Na-insertion and Na-extraction mainly occurred at ,51G- V and at -52G25- V vs. Na+/Na (Figure S9). These 5 ACS Paragon Plus Environment



Page 6 of 15

Page 7 of 15 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





Page 8 of 15

Page 9 of 15

Ta-doped TiO2 is expected to have larger discharge capacities at high current rates because Na+-diffusion path was expanded and its charge density was lowered. Figure 5 compares rate capabilities of Ta-doped TiO2 electrode and other-element-doped ones. To evaluate the potential performances, the rate capability tests were subsequently carried out after the capacity decay/rising in the initial ten cycles at their cycling tests. As we predicted, Ta-doped TiO2 electrode exhibited superior rate performances: the discharge capacities at the all C-rates from 0.15 C to 20 C were higher than those of the other electrodes. The capacity of 130 mA h gG, was attained even at a high current density of 10 C (3.35 mA gG,), which is much higher than that of undoped anatase TiO2 (40 mA h gG, at 10 C)2, Mo-doped anatase (100 mA h gG, at 5 C)26, Co-doped anatase (85 mA h gG, at 6 C)27, and (N, S)-doped anatase (90 mA h gG, at 6 C).28 The outstanding rate capability is attributed to the three effects of Ta doping: (i) expanded diffusion path, (ii) improved electronic conductivity, and (iii) reduced electron charge density in the path. This doping strategy gives a valuable information for new material design of TiO2-based anode materials. As the concept of Nb doping7 has been intensively applied to various rutile TiO28,9,19,20 and anatase TiO221-28, the strategy of Ta doping also will trigger to develop new TiO2-based anode materials.

0.15 C

1

Discharge capacity / mA h g

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


250

0.3 C

1.5 C

3.0 C

5.0 C

10 C

20 C

0.15 C

Ta-doped TiO2 200

In-doped TiO2

150 100

Nb-doped TiO2 Undoped TiO2

50

Sn-doped TiO2 (1 C = 335 mA g 1 )

0

0

5

10

15

20

25

30

35

40

Cycle number Figure 5 Rate capabilities of Ta-doped TiO2 electrode and other-element-dopedTiO2 electrodes. To evaluate the potential performances, rate capability tests were



Page 10 of 15

4. Conclusions To further enhance Na-storage performance of rutile TiO2 with ion-diffusion path along its caxis direction, we hydrothermally synthesized various element-doped TiO2 using Ta5+, Nb5+, Sn4+, and In3+ with larger ionic sizes and higher effective nuclear charges than those of Ti4+. 6.7 at.% of Ta5+ and 5.7 at.% of Nb5+ were successfully doped into rutile, whereas the doping amounts of Sn4+ and In3+ reached only 2.6 at.% and 0.5 at.% because of their too larger ionic sizes than Ti4+. Owing to these low doping amounts, the Sn- and In-doped TiO2 electrodes showed inferior performances as NIB anode to that of undoped one. On the other hand, the Ta- and Nb-doped TiO2 electrodes exhibited larger discharge capacities, which is attributed to the two doping effects: an expanded diffusion path and an improved electronic conductivity. In particular, the Ta-doped one delivered the highest initial capacity of 290 mA h gG,. As the results of first principle calculation, we revealed that Ta doping could reduce the charge density in the diffusion path more effectively because Ta5+ has a larger effective nuclear charge (20.5) than Nb5+ (14.1) to attract more strongly outermost electron existing in the path. Therefore, Na+ was not bound by electron in the path to diffuse toward the inner part of TiO2 particle, which leads to the enhancement of the discharge capacity. As we expected, Ta-doped TiO2 electrode exhibited an excellent rate performance with the reversible capacity of 130 mA h gG, even at a high current density of 10 C (3.35 mA gG,). These results demonstrated the significance of the third effect of doping: the reduction of electron charge density in the Na+-diffusion path.

ACKNOWLEDGMENT This study was partially supported by Japan Society for the Promotion of Science (JSPS) KAKENHI (Grant Number 19H02817, 17H03128, 17K17888, 16K05954). A part of this work was supported by the Japan Association for Chemical Innovation (JACI). The authors appreciate Mr. S. Ohnishi and Ms. R. Takaishi for their assistances of hydrothermal synthesis of doped TiO2 samples and discussion of first principle calculation results.


Page 11 of 15 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


ORCID Hiroyuki Usui: 0000-0002-1156-0340 Yasuhiro Domi: 0000-0003-3983-2202 Hiroki Sakaguchi: 0000-0002-4125-7182

ASSOCIATED CONTENT Supporting Information Preparation of active materials, Conditions of first-principle calculation, XRD patterns, SEM images, Charge–discharge curves.

AUTHOR INFORMATION Corresponding Author: Hiroki Sakaguchi

*Email: [email protected]



Page 12 of 15

REFERENCES (1) Myung, S.-T.; Maglia, F.; Park, K.-J.; Yoon, C. S.; Lamp, P.; Kim, S.-J.; Sun, Y.-K. NickelRich Layered Cathode Materials for Automotive Lithium-Ion Batteries: Achievements and Perspectives. ACS Energy Lett. 2017, 2, 196G223. (2) Kim, K.-T.; Ali, G.; Chung, K. Y.; Yoon, C. S.; Yashiro, H.; Sun, Y.-K.; Lu, J.; Amine, K.; Myung, S.-T. Anatase Titania Nanorods as an Intercalation Anode Material for Rechargeable Sodium Batteries. Nano Lett. 2014, 14, +,/G+225 (3) Huang, J. P.; Yuan, D. D.; Zhang, H. Z.; Cao, Y. L.; Li, G. R.; Yang, H. X.; Gao, X. P. Electrochemical Sodium Storage of TiO2(B) Nanotubes for Sodium Ion Batteries. RSC Adv. 2013, 3, ,21H;G,2/-;5 (4) Senguttuvan, P.; Rousse, G.; Seznec, V.; Tarascon, J.-M.; Palacín, M. R. Na2Ti3O7: Lowest Voltage Ever Reported Oxide Insertion Electrode for Sodium Ion Batteries. Chem. Mater. 2011, 23, +,-HG+,,,5 (5) Shen, K.; Wagemaker, M. Na2+xTi6O13 as Potential Negative Electrode Material for Na-Ion Batteries. Inorg. Chem. 2014, 53, 021-G021/5 (6) Zhang, Y.; Hou, H.; Yang, X.; Chen, J.; Jing, M.; Wu, Z.; Jia, X.; Ji, X. Sodium Titanate Cuboid as Advanced Anode Material for Sodium Ion Batteries. J. Power Sources 2016, 305, 2--G2-05 (7) Usui, H.; Yoshioka, S.; Wasada, K.; Shimizu, M.; Sakaguchi, H. Nb-Doped Rutile TiO2: a Potential Anode Material for Na-Ion Battery. ACS Appl. Mater. Interfaces 2015, 7, /1/:G/1:;5 (8) Usui, H.; Domi, Y.; Yoshioka, S.; Kojima, K.; Sakaguchi, H. Electrochemical Lithiation and Sodiation of Nb-Doped Rutile TiO2. ACS Sustainable Chem. Eng. 2016, 4, //H1G/:-25 (9) Usui, H.; Domi, Y.; Shimizu, M.; Imoto, A.; Yamaguchi, K.; Sakaguchi, H. Niobium-Doped Titanium Oxide Anode and Ionic Liquid Electrolyte for a Safe Sodium-Ion Battery. J. Power Sources 2016, 329, +20G+;,5 (10) Furubayashi, Y.; Hitosugi, T.; Yamamoto, Y.; Inaba, K.; Kinoda, G.; Hirose, Y.; Shimada, T.; Hasegawa, T. A transparent metal: Nb-doped anatase TiO2. Appl. Phys. Lett. 2005, 86, 252101. (11) Hitosugi, T.; Kamisaka, H.; Yamashita, K.; Nogawa, H.; Furubayashi, Y.; Nakao, S.; Yamada, N.; Chikamatsu, A.; Kumigashira, H.; Oshima, M. Electronic Band Structure of Transparent Conductor: Nb-Doped Anatase TiO2. Appl. Phys. Express, 2008, 1, 111203. (12) Yamamoto, T.; Ohno, T. Screened hybrid density functional study on Nb- and Ta-doped TiO2. Phys. Rev. B 2012, 85, 033104. (13) Hong, Z.; Zhou, K.; Zhang, J.; Huang, Z.; Wei, M. Facile synthesis of rutile TiO2 mesocrystals with enhanced sodium storage properties. J. Mater. Chem. A 2015, 3, ,:+,2G,:+,/5


Page 13 of 15 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


(14) Zhang, Y.; Pu, X.; Yang, Y.; Zhu, Y.; Hou, H.; Jing, M.; Yang, X. Chen, J.; Ji. X. An electrochemical investigation of rutile TiO2 microspheres anchored by nanoneedle clusters for sodium storage. Phys. Chem. Chem. Phys. 2015, 17, ,1:/+G,1::-5 (15) Zhang, Y.; Foster, C. W.; Banks, C. E.; Shao, L.; Hou, H.; Zou, G.; Chen, J.; Huang, Z.; Ji, X. Graphene-Rich Wrapped Petal-Like Rutile TiO2 tuned by Carbon Dots for High-Performance Sodium Storage. Adv. Mater. 2016, 28, H;H,GH;HH (16) Hong, Z.; Hong, J.; Xie, C.; Huang, Z.; Wei, M. Hierarchical rutile TiO2 with mesocrystalline structure for Li-ion and Na-ion storage. Electrochim Acta 2016, 202, 2-;G2-05 (17) Gu, X.; Li, L.; Wang, Y.; Dai, P.; Wang, H.; Zhao, X. Hierarchical tubular structures constructed from rutile TiO2 nanorods with superior sodium storage properties. Electrochim Acta 2016, 211, ::G025 (18) Lan, T.; Wang, T.; Zhang, W.; Wu, N.-L.; Wei, M. Rutile TiO2 mesocrystals with tunable subunits as a long-term cycling performance anode for sodium-ion batteries. J. Alloys Compd. 2017, 699, +11G+/25 (19) He, H.; Wang, H.; Sun, D.; Shao, M.; Huang, X.; Tang, Y. N-doped rutile TiO2/C with significantly enhanced Na storage capacity for Na-ion batteries. Electrochim. Acta 2017, 236, +;G125 (20) He, H.; Sun, D.; Zhang, Q.; Fu, F.; Tang, Y.; Guo, J.; Shao, M. Wang, H. Iron-Doped Cauliflower-Like Rutile TiO2 with Superior Sodium Storage Properties. ACS Appl. Mater. Interfaces 2017, 9, /-H;G/,-;5 (21) Zhao, F.; Wang, B. Tang, Y.; Ge, H.; Huang, Z.; Liu, H. K. Niobium doped anatase TiO2 as an effective anode material for sodium-ion batteries. J. Mater. Chem. A 2015, 3, 22H/HG22H:+5 (22) Yue, J.; Suchomski, C.; Voepel, P.; Ellinghaus, R.; Rohnke, M.; Leichtweiss, T.; Elm, M. T.; Smarsly, B. M. Mesoporous niobium-doped titanium dioxide films from the assembly of crystalline nanoparticles: study on the relationship between the band structure, conductivity and charge storage mechanism. J. Mater. Chem. A 2017, 5, ,H:0G,H005 (23) Hwang, K.; Sohn, H.; Yoon, S. Mesostructured niobium-doped titanium oxide-carbon (NbTiO2-C) composite as an anode for high-performance lithium-ion batteries. J. Power Sources 2018, 378, 221G2;+5 (24) Tanaka, Y.; Usui, H.; Domi, Y.; Ohtani, M.; Kobiro, K.; Sakaguchi, H. Mesoporous Spherical Aggregates Consisted of Nb-Doped Anatase TiO2 Nanoparticles for Li and Na Storage Materials. ACS Appl. Energy Mater. 2019, 2, /;/G/+;5 (25) Yan, D.; Yu, C.; Li, D.; Zhang, X.; Li, J.; Lu, T.; Pan, L. Improved sodium-ion storage performance of TiO2 nanotubes by Ni2+ doping. J. Mater. Chem. A 2016, 4, ,,-::G,,-015



Page 14 of 15

(26) Liao, H. Xie, L.; Zhang, Y.; Qiu, X.; Li, S.; Huang, Z.; Hou, H.; Ji, X. Mo-doped Gray Anatase TiO2: Lattice Expansion for Enhanced Sodium Storage. Electrochim. Acta 2016, 4, ,,-::G,,-015 (27) Hong, Z. S.; Kang, M. L.; Chen, X. H.; Zhou, K. Q.; Huang, Z. G.; Wei, M. D. Synthesis of Mesoporous Co2+-Doped TiO2 Nanodisks Derived from Metal Organic Frameworks with Improved Sodium Storage Performance. ACS Appl. Mater. Interfaces 2017, 9, ;2-:,G;2-:H5 (28) Li, F. Q.; Liu, W. W.; Lai, Y. Q.; Qin, F. R.; Zou, L.; Zhang, K.; Li, J. Nitrogen and sulfur co-doped hollow carbon nanofibers decorated with sulfur doped anatase TiO2 with superior sodium and lithium storage properties. J. Alloys Compd. 2017, 695, ,:+;G,:125 (29) Steele, J. L.; MacCartney, E. R. Anisotropy of Diffusion in Rutile. Nature 1969, 222, 79. (30) Koudriachova, M. V.; Harrison, N. M.; de Leeuw, S. W. Diffusion of Li-ions in rutile. An ab initio study. 2003, 157, ;1G;05


Page 15 of 15 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



Tantalum-Doped Titanium Oxide with Rutile Structure as a Novel

Recommend Documents