Zn Textile Battery with High

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Weavable, Conductive Yarn-Based NiCo//Zn Textile Battery with High Energy Density and Rate Capability Yan Huang,† Wing Shan Ip,† Yuen Ying Lau,† Jinfeng Sun,‡ Jie Zeng,§ Nga Sze Sea Yeung,∥ Wing Sum Ng,∥ Hongfei Li,† Zengxia Pei,† Qi Xue,† Yukun Wang,† Jie Yu,§ Hong Hu,∥ and Chunyi Zhi*,† †

Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Hong Kong, China School of Material Science and Engineering, University of Jinan, Jinan 250022, China § Department of Material Science and Engineering, Shenzhen Graduate School, Harbin Institute of Technology, University Town, Shenzhen 518055, China ∥ Institute of Textiles and Clothing, The Hong Kong Polytechnic University, 11 Hong Chong Road, Hong Kong, China ‡

S Supporting Information *

ABSTRACT: With intrinsic safety and much higher energy densities than supercapacitors, rechargeable nickel/cobalt− zinc-based textile batteries are promising power sources for next generation personalized wearable electronics. However, high-performance wearable nickel/cobalt−zinc-based batteries are rarely reported because there is a lack of industrially weavable and knittable highly conductive yarns. Here, we use scalably produced highly conductive yarns uniformly covered with zinc (as anode) and nickel cobalt hydroxide nanosheets (as cathode) to fabricate rechargeable yarn batteries. They possess a battery level capacity and energy density, as well as a supercapacitor level power density. They deliver high specific capacity of 5 mAh cm−3 and energy densities of 0.12 mWh cm−2 and 8 mWh cm−3 (based on the whole solid battery). They exhibit ultrahigh rate capabilities of 232 C (liquid electrolyte) and 116 C (solid electrolyte), which endows the batteries excellent power densities of 32.8 mW cm−2 and 2.2 W cm−3 (based on the whole solid battery). These are among the highest values reported so far. A wrist band battery is further constructed by using a large conductive cloth woven from the conductive yarns by a commercial weaving machine. It powers various electronic devices successfully, enabling dual functions of wearability and energy storage. KEYWORDS: aqueous rechargeable battery, conductive yarns, weavability, wearability, energy density, rate capability

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capacity and thus deliver higher energy density than individual transition metal counterparts.7−9 However, no work has been reported on the Zn-based yarn batteries by utilization of highly conductive yarns, which can be industrially weavable and

earable aqueous rechargeable batteries have received increasing attention for personalized electronics due to their intrinsic safety and low cost.1 The Ni//Zn batteries based on weavable and knittable highly conductive yarns are, in particular, promising because of their high output voltage (≈1.8 V) compared to that of other aqueous batteries (most ≤1.2 V) and their similarity with traditional textiles.2−6 Originating from the synergistic effects between transition metal ions, bimetallic (Ni, Co) hydroxides present higher © 2017 American Chemical Society

Received: May 12, 2017 Accepted: August 16, 2017 Published: August 16, 2017 8953

DOI: 10.1021/acsnano.7b03322 ACS Nano 2017, 11, 8953−8961

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Figure 1. Demonstration and schematics of conductive yarns. (a) Flexibility demonstration: a long yarn bent and knotted to various patterns. The enlarged image is a scanning electron microscopy (SEM) photo of the yarn. Scale bar: 100 μm. (b) Industrial weavability and knittability demonstration: a cloth woven by a CCI Rapier weaving machine (left) and a cloth knitted by a STOLL knitting machine (right). Scale bars: 1 cm. (c) Yarns electrodeposited with Zn and NCHO. (d) Schematics of a free-standing solid-state yarn battery.

mWh cm−2 and 8 mWh cm−3, and power densities of 32.8 mW cm−2 and 2.2 W cm−3 (all based on the solid battery), being superior to most aqueous batteries and supercapacitors to the best of our knowledge. In particular, they demonstrate ultrahigh rate capability of 232 C (liquid-state electrolyte) and 116 C (solid-state electrolyte). As a demonstration of wearable energy storage textile, a wrist band battery is fabricated by weaving a large conductive cloth from the conductive yarns with the use of a commercial weaving machine, which effectively powers various electronic devices including a watch, a set of lightemitting diodes, and a pulse sensor.

knittable. It would therefore be of tremendous interest to develop wearable NiCo//Zn batteries exhibiting superior capacity and energy and power densities based on such yarns. This will greatly boost textile energy storage technologies for personalized wearable electronic applications. This high-performance wearable battery imposes two considerable requirements for yarn electrodes: high electric conductivity and high mechanical strength. On one hand, the much higher capacity of batteries compared with that of supercapacitors and the long-distance one-dimensional electronic transportation in the yarn both raise a much more critical requirement on the conductivity of yarns. On the other hand, a tensile stress at the magnitude of MPa from industrial weaving and knitting machines is always imposed on the yarn. Even much worse, it exponentially increases at the contact region of yarns and metallic parts because of friction. So, industrial weaving and knitting require yarns that can endure high stress. Metals could provide a perfect solution to these requirements. Compared with other materials, they have both excellent conductivity and strength. More importantly, it is found that stainless steel 316L can be spun at high temperature to form micron-sized filaments, followed by a twist-bundledrawing technique to continuously produce yarns. This perfectly solves the challenges of weavability, knittability, and wearability encountered by conventional metallic wires. These large-scale-yield yarns provide flexibility similar to cotton yarns. In this paper, wearable high-performance NiCo//Zn batteries are fabricated by uniform electrodeposition of zinc (Zn, as anode) and nickel cobalt hydroxide (NCHO, as cathode) nanosheets on these highly conductive yarns. They exhibit a high specific capacity of 5 mAh cm−3, energy densities of 0.12

RESULTS AND DISCUSSION Synthesis of Zn@Conductive Yarns and NCHO@ Conductive Yarns. Thanks to the development of the modern textile industry, stainless steel 316L is continuously spun to ultrathin filaments and further twisted to yarns. Arising from the intrinsic flexibility of micron-sized stainless steel 316L filaments, the as-drawn highly conductive long yarns are as flexible as cotton yarns (Figure 1a). Their average diameter is 180−250 μm, which is similar to that of cotton yarns. More importantly, they can undergo industrial weaving and knitting. For example, a CCI Rapier weaving machine and a STOLL knitting machine posing stresses of hundreds of MPa were used to weave and knit large cloths easily (≥10 cm × 10 cm) (Figure 1b). They can also suffer hand knitting to make various arbitrary patterns without any breakage (Supplementary Figure S1). The good electrical conductivity of stainless steel 316L yarns guarantees one-dimensional long-distance electron transport 8954

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Figure 2. Morphology characterization. (a) Yarn electrodeposited with Zn. Scale bar: 100 μm. (b) Zn nanoflakes. Scale bar: 1 μm. (c) Conductive yarn electrodeposited with NCHO. Scale bar: 50 μm. (d) Ultrathin NCHO mesoporous nanosheets. Scale bar: 500 nm.

Figure 3. XRD and XPS characterization. (a) XRD pattern of the electrodeposited Zn on the conductive yarn. (b) XPS spectrum of Ni 2p. (c) XPS spectrum of Co 2p. (d) XPS spectrum of O 1s of the ultrathin mesoporous NCHO nanosheets.

and uniform electrodepositon of active materials.10,11 As illustrated in Figure 1c, Zn and NCHO were grown on the yarns. Before electrodeposition, the as-drawn conductive yarns are hydrothermally treated in alkaline solution. By doing so, hydrophilic hydroxyl groups improve the wettability greatly (Supplementary Figure S2) and thus favor the uniform electrodeposition of Zn and NCHO. For the fabrication of free-standing solid-state yarn batteries, poly(vinyl alcohol) (PVA)-based gel electrolyte is coated on the electrodeposited Zn and NCHO without binder or separator (Figure 1d).

Characterization of Conductive Yarn Electrodes. The high conductivtiy- and wettability-induced uniform deposition plays a crucial role in achieving high performances of batteries. Zn nanoflakes and NCHO untrathin mesoporous nanosheets are both grown on the filaments uniformly (Figure 2). The atomic ratio of NCHO is ca. 1:1:3 (Ni/Co/O), being consistent with that of Ni to Co in the precursor electrolyte (Supplementary Figure S3). Electroplating is a general approach to obtain the Zn anode with the nanoflake structure.9 The mesoporous nanosheet structure is very typical in transition metal oxides/hydroxides such as Ni, Co, Ni−Co, 8955

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Figure 4. Electrochemical performance of the yarn batteries measured in liquid electrolyte. (a) CV at 5 mV/s. (b) GCD from 0.031 A/cm3 (1.45 C) to 5 A/cm3 (232 C) normalized to two yarn electrodes. (c) Volumetric capacities normalized to two yarn electrodes. (d) Capacity retention during charge/discharge cycles. (e) Length capacity with respect to the length of highly conductive yarn.

etc. Various synthesis methods like electrodeposition3,8,9 and solvothermal6 can obtain the mesoporous nanosheet structure with similar pore size around 100−300 nm, which was demonstrated to be critical for the superior electrochemical performances.8 These nanoflakes/nanosheets with thin and porous features greatly increase the effective surface area and promise fast ion transport during charge/discharge, which favor fast electrochemical kinetics. These as-electrodeposited Zn and NCHO are also investigated by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) (Figure 3). The XRD pattern shows a crystalline structure of the electroplated Zn (Figure 3a). The elemental composition and oxidation states of NCHO can be obtained from XPS. Besides two satellite peaks (noted as “Sat.”), the Ni 2p spectrum contains typical peaks located at 855.6 and 873.3 eV, characteristic of Ni3+ (Figure 3b). The Co 2p spectrum suggests the existence of Co3+ and Co2+ (Figure 3c). The atomic ratio of Co3+ to Co2+ is calculated to be 1:1 according to their peak areas integrated from the XPS spectrum. The O 1s spectrum shows OH groups at 531.1 eV and defect sites at 533.4 eV, which are usually observed in nanostructured materials (Figure 3d).12 These data show that the surface composition of the hydroxylated NCHO contains Ni3+, Co3+, and Co2+. Combined with the aforementioned

elemental atomic ratio, the formula of NCHO could thus be approximately expressed as Ni3+Co2+0.5Co3+0.5O3H0.5. Electrochemical Performances of Yarn Batteries in the Liquid Electrolyte. We optimized NCHO and Zn electrodes as well as the liquid electrolyte. The time of electrodeposition obviously affects the electrochemical performance of NCHO (Supplementary Figure S4). The capacity greatly increases with the NCHO electrodeposition time and then decreases. In addition, the capacity with the absence of Ni or Co is inferior to that of the bimetallic NCHO (Supplementary Figure S5). This is contributed to the synergistic effect between Ni and Co that Co3+ accommodates the detrimental Jahn−Teller distortion of Ni3+ and therefore stabilizes their framework.7 By contrast, in the time of Zn electroplating we studied, Zn is always over the amount, and therefore, the capacity just slightly increases with the Zn electrodeposition time (Supplementary Figure S6). Besides electrode optimization, the liquid electrolyte is optimized to be 6 M KOH due to its good ionic conductivity and low viscosity (Supplementary Figure S7).13,14 A full scenario of the electrochemical performance in liquid electrolyte is obtained on the optimized yarn battery. The battery shows strong redox peaks at ≈1.65 and ≈1.85 V at 5 mV s−1 (Figure 4a), which are responsible to the overall electrochemical reaction:9,15,16 8956

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Figure 5. Electrochemical performance of the solid-state yarn batteries. (a) CV at 5 mV/s and 10 mV/s. (b) GCD from 18.7 mA/cm3 (1.45 C) to 1.5 A/cm3 (116 C). (c) Ragone plot comparing aqueous batteries and asymmetric supercapacitors. (d) Electrochemical performances of batteries and supercapacitors: volumetric capacities (CV), areal (EA) and volumetric (EV) energy densities, areal (PA) and volumetric (PV) power densities. Data of our work are all normalized to the whole battery including two yarn electrodes and solid electrolyte.

mAh g−1NCHO). Such high rate capability reveals that these yarn batteries endure fast charging. All these GCD curves demonstrate charge and discharge plateaus with a small voltage hysteresis of ≈0.1 V. Specific capacities normalized to volume (CV) of the two yarn electrodes are displayed in Figure 4c. At a low current density of 31 mA cm−3, which corresponds to 0.54 h discharge time, the NiCo//Zn battery delivers a high capacity

Zn + NiOOH + CoOOH + 2KOH + 2H 2O discharge

HooooooooI K 2[Zn(OH)4 ] + Ni(OH)2 + Co(OH)2 charge

Figure 4b shows the galvanostatic charge−discharge (GCD) curves from 0.031 to 5 A cm−3 (normalized to the sum of two yarn electrodes), corresponding to 1.45 to 232 C (1 C = 242 8957

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Figure 6. Flexibility tests of solid-state yarn batteries. (a) GCD curves under consecutive deformations. (b) Capacity ratio at various deformation states. (c) GCD curves undergoing various times of bending. (d) GCD curves undergoing various times of twisting. (e) Cycle stability under deformation states.

of 16.6 mAh cm−3 (normalized to the sum of two yarn electrodes). To our best knowledge, it is the highest value among all reported fiber-based energy storage devices, even when compared with those values calculated from single yarn electrode (Supplementary Table S1).17,18 When the current density increases 40 and even 80 times, 65 and 51% of the initial capacity could still be maintained, respectively, revealing the excellent rate capability. Figure 4d shows that the yarn battery retains 60% capacity after 1000 cycles, demonstrating better performance stability than other batteries, such as NiO// Zn (65% after 500 cycles),19 Ni(OH)2//Bi2O3 (60% after 200 cycles),20 Zn//LiFePO4 (≈78% after 400 cycles)21 etc. The good capacities of the yarn battery fundamentally result from the excellent conductivity of our yarns. Usually, the capacity normalized to the length of conductive yarns decreases with the increase of length. By contrast, our highly conductive yarns show an almost constant capacity per length (Figure 4e and Supplementary Figure S8). It is the excellent conductivity that makes electron transport fast and the small ohmic resistance of yarns ignorable in the electrochemical dynamic processes. It is also the excellent conductivity that makes multiple tiny filaments be uniformly wrapped with Zn nanoflakes and ultrathin mesoporous NCHO nanosheets,

therefore providing maximum surface for electrochemical processes. It should be noted that the bare stainless steel yarn barely contributes capacity (Supplementary Figure S9). Therefore, the potential effect of Ni−Fe can be ruled out. Electrochemical Performances of Solid-State Yarn Batteries. To fabricate the solid-state yarn battery, two parallel yarn electrodes were coated with a PVA-KOH-Zn(CH3COO)2 gel electrolyte without binder or separator. The total volume of yarn battery, including two yarn electrodes and the surrounding solid electrolyte, is estimated to be 0.00375 cm3 (Supplementary Figure 10). The yarn battery displays typical CV curves (Figure 5a) and GCD profiles from 18.7 mA cm−3 (1.45 C) to 1.5 A cm−3 (116 C) (Figure 5b).22,23 The achieved specific capacity of 5 mAh cm−3 (based on the whole battery) outperforms many single yarn electrodes even measured in liquid electrolytes (Supplementary Table 1). The battery delivers maximum volumetric/areal energy densities of 8 mWh cm−3 and 0.12 mWh cm−2 and power densities of 2.2 W cm−3 and 33 mW cm−2. They are considerably superior to those of Ni//Zn battery,16 Ni//Fe battery,24 Li thin-film battery,25 and asymmetric supercapacitors (Figure 5c and Supplementary Figure S11).17,26−34 These energy and power densities are among the highest values to 8958

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Figure 7. Electrochemical performance of multiple yarn batteries and photographs of the energy wrist band made of yarn batteries. (a) Discharge curves of in-series batteries. (b) Discharge curves of in-parallel batteries. (c) Energy wrist band made of a woven cloth powers a watch (left), a set of LEDs (upper right), and a pulse sensor (bottom right).

textiles. By using the large conducting cloth woven by the CCI Rapier weaving machine as shown in Figure 1b, we fabricated an energy wrist band with four to five textile batteries connectecd in series (Figure 7c). Besides weavability and wearability, this charged energy wrist band has successfully powered a watch, a set of light-emitting diodes, and a pulse sensor, demonstrating its promising potential in personalized wearable electronics and healthcare.

date (Figure 5d), even superior to those calculated by a single electrode (Supplementary Table S1).10,16−18,24−45 As aforementioned, the excellent conductivity of yarns fundamentally contributes to the superior performances of yarn batteries. The yarn battery experienced a series of deformation tests: straight, bent 95°, twisted 360°, and again straight (Figure 6a). The charge curves almost overlap completely, and discharge curves as well as capacities do not change much at various deformation states. After experiencing these nonplanar deformations, the yarn battery retained 78% of initial capacity (Figure 6b). Cycling tests at different deformation states are shown in Figure 6c,d. Under bent 95° and twisted 360°, the battery researves over 80 and 70% of initial capacity after 1000 times, respectively (Figure 6e). The capacity loss probably arises from cracks formed on the electrode materials during mechanical deformation (Supplementary Figure S12). Being different from those intrinsically flexible polymers and carbon materials, metal oxides are vulnerable to break and produce cracks upon deformation. Wear Textile Batteries Made of Industrially Weavable Highly Conductive Yarns. Multiple yarn batteries can be assembled in different ways. The two-in-series has a two-fold wider voltage window (2.4−4 V), and the four-in-series works in a four-fold window (4.8−8 V) with similar capacity (Figure 7a). Similarly, the three-in-parallel has a three-fold higher current, suggesting a good scalability (Figure 7b). Therefore, industrial weavability, flexibility, and scalability validate energy

CONCLUSIONS We developed high-performance aqueous recharge NiCo//Zn textile batteries by using industrially weavable and knittable highly conductive yarns. The excellent conductivity of yarns and their intimate electrodeposition of high-surface electrode nanomaterials guarantee fast electron and ion transport. The fabricated yarn batteries deliver high specific capacity of 5 mAh cm−3, energy densities of 0.12 mWh cm−2 and 8 mWh cm−3, power densities of 32.8 mW cm−2 and 2.2 W cm−3 (all based on the whole solid battery), as well as ultrahigh rate capability of 232 C (liquid electrolyte) and 116 C (solid electrolyte), which are superior to most aqueous batteries and supercapacitors even normalized to a single electrode. Their good weavability, flexibility and scalability enable the construction of an energy wrist band, which effectively powers various electronic devices. Our work well connects textile industry with personalized wearable electronics and healthcare. 8959

DOI: 10.1021/acsnano.7b03322 ACS Nano 2017, 11, 8953−8961

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EXPERIMENTAL SECTION

ORCID

Synthesis of Zn- and NCHO-Electrodeposited Conductive Yarn Electrodes. Pristine yarns were cleaned by acetone, ethanol, and deionized water. Then they were hydrothermally treated at 180 °C for 12 h in a 45 mL Teflon-lined stainless steel autoclave containing 1 M NaOH (20 μL) and 20 mL of deionized water. Yarn anodes were made by Zn electrodeposition at −0.8 V vs Zn foil for 10−240 s in 1 M zinc sulfate at room temperature. Yarn cathodes were electrodeposited with NCHO at −1 V vs SCE for 1−30 min in a solution of 5 mM nickel nitrate and 5 mM cobalt nitrate at room temperature. Electrochemical Characterization of Yarn Batteries in Liquid Electrolyte. Capacity measurements were performed in a mixed aqueous electrolyte of 6 M KOH and 0.2 M zinc acetate with a CHI 760E potentiostat at room temperature. The Zn-electroplated yarn and the NCHO-electrodeposited yarn served as an anode and a cathode, respectively. Capacity of battery (C) was calculated based on the formula

Chunyi Zhi: 0000-0001-6766-5953

C=

It × 1000 3600

Notes

The authors declare no competing financial interest.

ACKNOWLEDGMENTS This work was supported by NSFC/RGC Joint Research Scheme (N_CityU123/15), City University of Hong Kong (PJ7004645), the Science Technology and Innovation Committee of Shenzhen Municipality (JCYJ20130401145617276 and R-IND4903), Jinan University (1009411), and the Hong Kong Polytechnic University (1BBA3). The authors are grateful for experimental help from T.F. Hung and W. Wong. REFERENCES

(1)

(1) Kim, H.; Hong, J.; Park, K. Y.; Kim, H.; Kim, S. W.; Kang, K. Aqueous Rechargeable Li and Na Ion Batteries. Chem. Rev. 2014, 114, 11788−11827. (2) Zeng, Y. X.; Lin, Z. Q.; Meng, Y.; Wang, Y. C.; Yu, M. H.; Lu, X. H.; Tong, Y. X. Flexible Ultrafast Aqueous Rechargeable Ni//Bi Battery Based on Highly Durable Single-Crystalline Bismuth Nanostructured Anode. Adv. Mater. 2016, 28, 9188−9195. (3) Liu, J. L.; Chen, M. H.; Zhang, L. L.; Jiang, J.; Yan, J. X.; Huang, Y. Z.; Lin, J. Y.; Fan, H. J.; Shen, Z. X. A Flexible Alkaline Rechargeable Ni/Fe Battery Based on Graphene Foam/Carbon Nanotubes Hybrid Film. Nano Lett. 2014, 14, 7180−7187. (4) Pan, H. L.; Shao, Y. Y.; Yan, P. F.; Cheng, Y. W.; Han, K. S.; Nie, Z. M.; Wang, C. M.; Yang, J. H.; Li, X. L.; Bhattacharya, P.; Mueller, K. T.; Liu, J. Reversible Aqueous Zinc/Manganese Oxide Energy Storage from Conversion Reactions. Nat. Energy 2016, 1, 16039. (5) Wang, G. J.; Yang, L. C.; Qu, Q. T.; Wang, B.; Wu, Y. P.; Holze, R. An Aqueous Rechargeable Lithium Battery Based on Doping and Intercalation Mechanisms. J. Solid State Electrochem. 2010, 14, 865− 869. (6) Lee, D. U.; Fu, J.; Park, M. G.; Liu, H.; Kashkooli, A. G.; Chen, Z. W. Self-Assembled NiO/Ni(OH)(2) Nanoflakes as Active Material for High-Power and High-Energy Hybrid Rechargeable Battery. Nano Lett. 2016, 16, 1794−1802. (7) Lee, J. H.; Lee, H. J.; Lim, S. Y.; Chae, K. H.; Park, S. H.; Chung, K. Y.; Deniz, E.; Choi, J. W. Stabilized Octahedral Frameworks in Layered Double Hydroxides by Solid-Solution Mixing of Transition Metals. Adv. Funct. Mater. 2017, 27, 1605225. (8) Yuan, C. Z.; Li, J. Y.; Hou, L. R.; Zhang, X. G.; Shen, L. F.; Lou, X. W. Ultrathin Mesoporous NiCo2O4 Nanosheets Supported on Ni Foam as Advanced Electrodes for Supercapacitors. Adv. Funct. Mater. 2012, 22, 4592−4597. (9) Xu, C.; Liao, J.; Yang, C.; Wang, R. Z.; Wu, D.; Zou, P. C.; Lin, Z. Y.; Li, B. H.; Kang, F. Y.; Wong, C. P. An Ultrafast, High Capacity and Superior Longevity Ni/Zn Battery Constructed on Nickel Nanowire Array Film. Nano Energy 2016, 30, 900−908. (10) Huang, Y.; Hu, H.; Huang, Y.; Zhu, M. S.; Meng, W. J.; Liu, C.; Pei, Z. X.; Hao, C. L.; Wang, Z. K.; Zhi, C. Y. From Industrially Weavable and Knittable Highly Conductive Yarns to Large Wearable Energy Storage Textiles. ACS Nano 2015, 9, 4766−4775. (11) Huang, Y.; Huang, Y.; Zhu, M. S.; Meng, W. J.; Pei, Z. X.; Liu, C.; Hu, H.; Zhi, C. Y. Magnetic-Assisted, Self-Healable, Yarn-Based Supercapacitor. ACS Nano 2015, 9, 6242−6251. (12) Jimenez, V. M.; Fernandez, A.; Espinos, J. P.; Gonzalezelipe, A. R. The State of the Oxygen at the Surface of Polycrystalline Cobalt Oxide. J. Electron Spectrosc. Relat. Phenom. 1995, 71, 61−71. (13) Li, Y. G.; Dai, H. J. Recent Advances in Zinc-Air Batteries. Chem. Soc. Rev. 2014, 43, 5257−5275. (14) See, D. M.; White, R. E. Temperature and Concentration Dependence of the Specific Conductivity of Concentrated Solutions of Potassium Hydroxide. J. Chem. Eng. Data 1997, 42, 1266−1268.

where I is the discharge current (A) and t is the dicharge time (s). The yarn battery is treated as a cube to calculate surface area (S) and volume (V) by

S = 2 × (a + b)L

(2)

V=a×b×L

(3)

where a is the length, b is the width, and L is the height of the yarn battery. Areal (CA) and volumetric (CV) capacities were determined by dividing the capacity of battery C by the area S and volume V, individually. Fabrication and Electrochemical Characterization of SolidState Yarn Batteries. PVA-KOH-Zn(CH3COO)2 gel electrolyte was prepared with 5 g of PVA, 5.05 g of KOH, 0.66 g of Zn(CH3COO)2 and 60 mL of deionized water at 90 °C. The cooled electrolyte was coated on yarn anodes and cathodes, followed by drying to form a gel at room temperature. The yarn batteries were tested by CV and GCD using the potentiostat (CHI 760E). The energy density was obtained from the discharge curves according to

E=

I∫ U (t )dt (4)

3600

where U(t) is the voltage during discharge (V). The power density was calculated by using the equation

P=

E × 3600 t

(5) −1

Derivation of 1 C = 242 mAh g NCHO. Based on the redox mechanism from +3 to +2 and the chemical formula Ni3+Co2+0.5Co3+0.5O3H0.5 obtained from XPS results discussed in the main text, the capacity of 1 C was calculated according to

1C =

(1 + 0.5) × F 3.6 × M

(6)

where F is the Faraday constant (96485 C/mol) and M is the molar mass of Ni3+Co2+0.5 Co3+0.5O3H0.5 (g/mol).

ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acsnano.7b03322. Experimental methods, supplementary Table S1, Figures S1−S12, and references (PDF)

AUTHOR INFORMATION Corresponding Author

*E-mail: [email protected]. 8960

DOI: 10.1021/acsnano.7b03322 ACS Nano 2017, 11, 8953−8961

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ACS Nano (15) Wang, X. W.; Wang, F. X.; Wang, L. Y.; Li, M. X.; Wang, Y. F.; Chen, B. W.; Zhu, Y. S.; Fu, L. J.; Zha, L. S.; Zhang, L. X.; Wu, Y. P.; Huang, W. An Aqueous Rechargeable Zn//Co3O4 Battery with High Energy Density and Good Cycling Behavior. Adv. Mater. 2016, 28, 4904−4911. (16) Liu, J. P.; Guan, C.; Zhou, C.; Fan, Z.; Ke, Q. Q.; Zhang, G. Z.; Liu, C.; Wang, J. A Flexible Quasi-Solid-State Nickel-Zinc Battery with High Energy and Power Densities Based on 3D Electrode Design. Adv. Mater. 2016, 28, 8732−8739. (17) Xu, J.; Wang, Q. F.; Wang, X. W.; Xiang, Q. Y.; Liang, B.; Chen, D.; Shen, G. Z. Flexible Asymmetric Supercapacitors Based Upon Co9S8 Nanorod//Co3O4@RuO2 Nanosheet Arrays on Carbon Cloth. ACS Nano 2013, 7, 5453−5462. (18) Yu, D. S.; Goh, K. L.; Zhang, Q.; Wei, L.; Wang, H.; Jiang, W. C.; Chen, Y. Controlled Functionalization of Carbonaceous Fibers for Asymmetric Solid-State Micro-Supercapacitors with High Volumetric Energy Density. Adv. Mater. 2014, 26, 6790−6797. (19) Xia, C.; Chen, W.; Wang, X. B.; Hedhili, M. N.; Wei, N. N.; Alshareef, H. N. Highly Stable Supercapacitors with Conducting Polymer Core-Shell Electrodes for Energy Storage Applications. Adv. Energy Mater. 2015, 5, 1401805. (20) Sun, J. F.; Wang, J. Q.; Li, Z. P.; Niu, L. Y.; Hong, W.; Yang, S. R. Assembly and Electrochemical Properties of Novel Alkaline Rechargeable Ni/Bi Battery Using Ni(OH)(2) and (BiO)(4)CO3(OH)(2) Microspheres as Electrode Materials. J. Power Sources 2015, 274, 1070−1075. (21) Yesibolati, N.; Umirov, N.; Koishybay, A.; Omarova, M.; Kurmanbayeva, I.; Zhang, Y. G.; Zhao, Y.; Bakenov, Z. High Performance Zn/LiFePO4 Aqueous Rechargeable Battery for Large Scale Applications. Electrochim. Acta 2015, 152, 505−511. (22) Liu, N. S.; Ma, W. Z.; Tao, J. Y.; Zhang, X. H.; Su, J.; Li, L. Y.; Yang, C. X.; Gao, Y. H.; Golberg, D.; Bando, Y. Cable-Type Supercapacitors of Three-Dimensional Cotton Thread Based MultiGrade Nanostructures for Wearable Energy Storage. Adv. Mater. 2013, 25, 4925−4931. (23) Tao, J. Y.; Liu, N. S.; Ma, W. Z.; Ding, L. W.; Li, L. Y.; Su, J.; Gao, Y. H. Solid-State High Performance Flexible Supercapacitors Based on Polypyrrole-MnO2-Carbon Fiber Hybrid Structure. Sci. Rep. 2013, 3, 2286. (24) Guan, C.; Zhao, W.; Hu, Y. T.; Ke, Q. Q.; Li, X.; Zhang, H.; Wang, J. High-Performance Flexible Solid-State Ni/Fe Battery Consisting of Metal Oxides Coated Carbon Cloth/Carbon Nanofiber Electrodes. Adv. Energy Mater. 2016, 6, 1601034. (25) Yu, D. S.; Goh, K.; Wang, H.; Wei, L.; Jiang, W. C.; Zhang, Q.; Dai, L. M.; Chen, Y. Scalable Synthesis of Hierarchically Structured Carbon Nanotube-Graphene Fibres for Capacitive Energy Storage. Nat. Nanotechnol. 2014, 9, 555−562. (26) Li, R. Z.; Wang, Y. M.; Zhou, C.; Wang, C.; Ba, X.; Li, Y. Y.; Huang, X. T.; Liu, J. P. Carbon-Stabilized High-Capacity Ferroferric Oxide Nanorod Array for Flexible Solid-State Alkaline BatterySupercapacitor Hybrid Device with High Environmental Suitability. Adv. Funct. Mater. 2015, 25, 5384−5394. (27) Zhou, C.; Zhang, Y. W.; Li, Y. Y.; Liu, J. P. Construction of High-Capacitance 3D CoO@Polypyrrole Nanowire Array Electrode for Aqueous Asymmetric Supercapacitor. Nano Lett. 2013, 13, 2078− 2085. (28) Lu, X. H.; Yu, M. H.; Wang, G. M.; Zhai, T.; Xie, S. L.; Ling, Y. C.; Tong, Y. X.; Li, Y. H-TiO2@MnO2//H-TiO2@C Core-Shell Nanowires for High Performance and Flexible Asymmetric Supercapacitors. Adv. Mater. 2013, 25, 267−272. (29) Yang, P. H.; Ding, Y.; Lin, Z. Y.; Chen, Z. W.; Li, Y. Z.; Qiang, P. F.; Ebrahimi, M.; Mai, W. J.; Wong, C. P.; Wang, Z. L. Low-Cost High-Performance Solid-State Asymmetric Supercapacitors Based on MnO2 Nanowires and Fe2O3 Nanotubes. Nano Lett. 2014, 14, 731− 736. (30) Zhu, C. R.; Yang, P. H.; Chao, D. L.; Wang, X. L.; Zhang, X.; Chen, S.; Tay, B. K.; Huang, H.; Zhang, H.; Mai, W. J.; Fan, H. J. All Metal Nitrides Solid-State Asymmetric Supercapacitors. Adv. Mater. 2015, 27, 4566−4571.

(31) Yu, M. H.; Han, Y.; Cheng, X. Y.; Hu, L.; Zeng, Y. X.; Chen, M. Q.; Cheng, F. L.; Lu, X. H.; Tong, Y. X. Holey Tungsten Oxynitride Nanowires: Novel Anodes Efficiently Integrate Microbial Chemical Energy Conversion and Electrochemical Energy Storage. Adv. Mater. 2015, 27, 3085−3091. (32) Zeng, Y. X.; Han, Y.; Zhao, Y. T.; Zeng, Y.; Yu, M. H.; Liu, Y. J.; Tang, H. L.; Tong, Y. X.; Lu, X. H. Advanced Ti-Doped Fe2O3@ PEDOT Core/Shell Anode for High-Energy Asymmetric Supercapacitors. Adv. Energy Mater. 2015, 5, 1402176. (33) Lu, X. H.; Yu, M. H.; Zhai, T.; Wang, G. M.; Xie, S. L.; Liu, T. Y.; Liang, C. L.; Tong, Y. X.; Li, Y. High Energy Density Asymmetric Quasi-Solid-State Supercapacitor Based on Porous Vanadium Nitride Nanowire Anode. Nano Lett. 2013, 13, 2628−2633. (34) Wang, X. F.; Liu, B.; Liu, R.; Wang, Q. F.; Hou, X. J.; Chen, D.; Wang, R. M.; Shen, G. Z. Fiber-Based Flexible All-Solid-State Asymmetric Supercapacitors for Integrated Photodetecting System. Angew. Chem., Int. Ed. 2014, 53, 1849−1853. (35) Bae, J.; Song, M. K.; Park, Y. J.; Kim, J. M.; Liu, M. L.; Wang, Z. L. Fiber Supercapacitors Made of Nanowire-Fiber Hybrid Structures for Wearable/Flexible Energy Storage. Angew. Chem., Int. Ed. 2011, 50, 1683−1687. (36) Chen, T.; Qiu, L. B.; Yang, Z. B.; Cai, Z. B.; Ren, J.; Li, H. P.; Lin, H. J.; Sun, X. M.; Peng, H. S. An Integrated ″Energy Wire″ for Both Photoelectric Conversion and Energy Storage. Angew. Chem., Int. Ed. 2012, 51, 11977−11980. (37) Pikul, J. H.; Zhang, H. G.; Cho, J.; Braun, P. V.; King, W. P. High-Power Lithium Ion Microbatteries from Interdigitated ThreeDimensional Bicontinuous Nanoporous Electrodes. Nat. Commun. 2013, 4, 1732. (38) Ren, J.; Li, L.; Chen, C.; Chen, X. L.; Cai, Z. B.; Qiu, L. B.; Wang, Y. G.; Zhu, X. R.; Peng, H. S. Twisting Carbon Nanotube Fibers for Both Wire-Shaped Micro-Supercapacitor and Micro-Battery. Adv. Mater. 2013, 25, 1155−1159. (39) Wu, X. C.; Lu, Z. Y.; Zhu, W.; Yang, Q.; Zhang, G. X.; Liu, J. F.; Sun, X. M. High-Performance Aqueous Battery with Double Hierarchical Nanoarrays. Nano Energy 2014, 10, 229−234. (40) Sun, K.; Wei, T. S.; Ahn, B. Y.; Seo, J. Y.; Dillon, S. J.; Lewis, J. A. 3D Printing of Interdigitated Li-Ion Microbattery Architectures. Adv. Mater. 2013, 25, 4539−4543. (41) Wang, H. L.; Liang, Y. Y.; Gong, M.; Li, Y. G.; Chang, W.; Mefford, T.; Zhou, J. G.; Wang, J.; Regier, T.; Wei, F.; Dai, H. J. An Ultrafast Nickel-Iron Battery from Strongly Coupled Inorganic Nanoparticle/Nanocarbon Hybrid Materials. Nat. Commun. 2012, 3, 917. (42) Yoshima, K.; Munakata, H.; Kanamura, K. Fabrication of Micro Lithium-Ion Battery with 3D Anode and 3D Cathode by Using Polymer Wall. J. Power Sources 2012, 208, 404−408. (43) Gaikwad, A. M.; Whiting, G. L.; Steingart, D. A.; Arias, A. C. Highly Flexible, Printed Alkaline Batteries Based on Mesh-Embedded Electrodes. Adv. Mater. 2011, 23, 3251−3255. (44) El-Kady, M. F.; Strong, V.; Dubin, S.; Kaner, R. B. Laser Scribing of High-Performance and Flexible Graphene-Based Electrochemical Capacitors. Science 2012, 335, 1326−1330. (45) Kou, L.; Huang, T. Q.; Zheng, B. N.; Han, Y.; Zhao, X. L.; Gopalsamy, K.; Sun, H. Y.; Gao, C. Coaxial Wet-Spun Yarn Supercapacitors for High-Energy Density and Safe Wearable Electronics. Nat. Commun. 2014, 5, 3754.

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DOI: 10.1021/acsnano.7b03322 ACS Nano 2017, 11, 8953−8961