Photopolymerization of Diacetylene on Aligned Multiwall Carbon

Letter www.acsami.org

Photopolymerization of Diacetylene on Aligned Multiwall Carbon Nanotube Microfibers for High-Performance Energy Devices Mani Ulaganathan,†,‡ Reinack Varghese Hansen,†,§ Nateisha Drayton,⊥,|| Hardik Hingorani,⊥ R. Govindan Kutty,# Hrishikesh Joshi,⊥ Sivaramapanicker Sreejith,*,⊥ Zheng Liu,# Jinglei Yang,△ and Yanli Zhao*,⊥,# ‡

Energy Research Institute, §School of Mechanical and Aerospace Engineering, and #School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Drive, 637553, Singapore ⊥ Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371 Singapore || L. G. Rich Environment Laboratory, Clemson University, 343 Computer Court, Clemson, South Carolina 29625, United States △ Department of Mechanical and Aerospace Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong S Supporting Information *

ABSTRACT: Linear two-dimensional materials have recently attracted an intense interest for supercapacitors because of their potential uses as electrodes in next-generation wearable electronics. However, enhancing the electrochemical properties of these materials without complicated structural modifications remains a challenge. Herein, we present the preparation of a hybrid electrode system via polydiacetylene (PDA) cloaking on the surface of aligned multiwall carbon nanotubes (MWCNTs) through self-assembly based in situ photopolymerization. This strategy eliminates the need for initiators and binders that hinder electrochemical performance in conventional conducting polymer based composite electrodes. As noncovalent PDA cloaking did not alter the chemical structure of MWCNTs, high inherent conductivity from sp2 hybridized carbon was preserved. The resulting hybrid microfiber (MWCNT@PDA) exhibited a significant increase in specific capacitance (1111 F g−1) when compared to bare MWCNTs (500 F g−1) and PDA (666.7 F g−1) in a voltage window of 0−1.2 V at a current density of 3 A g−1 in 0.5 M K2SO4 electrolyte. The specific capacitance was retained (ca. 95%) after 7000 charge/discharge cycles. The present results suggest that aligned MWCNTs cloaked with conjugated polymers could meet the demands for future flexible electronics. KEYWORDS: carbon nanotube, energy, polydiacetylene, photopolymerization, supercapacitor

T

properties of conducting polymers with CNTs, the resulting electrodes often suffered from poor cycle life, with either active materials peeling off or accumulating as inactive components under repeated charge/discharge cycles. Taking these factors into consideration, an ideal supercapacitor electrode should consist of a combination of well-aligned CNTs and other lessexpensive forms of carbon without insulating binder materials. In this context, aligned multiwall CNT (MWCNT) sheets, having high flexibility, excellent electrical conductivity, and easy functionalization, drawn from vertically aligned CNT arrays are suitable candidates.18−28 In this paper, we designed a hybrid material (MWCNT@ PDA) composed of aligned MWCNT sheets and conducting polydiacetylene (PDA) supported on a standard graphite paper

he need for alternative sources of energy has triggered an extensive research on supercapacitors. The application potential of supercapacitors in devices demanding high power density, immediate release of stored charge and significantly high cycle life remains promising.1−4 Recently, fiber-based devices have garnered a lot of curiosity owing to their ease of integration in portable and wearable electronics.5−11 Among various materials explored for uses as supercapacitor electrodes in wearable electronics, high surface area, and good performance of carbonaceous materials such as carbon nanotubes (CNTs) and graphene have made them favorable candidates.12−15 Electrodes purely based on graphene and CNTs are mechanically more stable but commercially expensive. Moreover, in the case of solution-processed CNTs, a random orientation of active CNTs on the electrode surface often results in the charge transfer resistance and therefore inferior electrochemical performance.16,17 Although research attempts have been made to combine the favorable pseudocapacitive © XXXX American Chemical Society

Received: September 25, 2016 Accepted: November 21, 2016 Published: November 21, 2016 A

DOI: 10.1021/acsami.6b12171 ACS Appl. Mater. Interfaces XXXX, XXX, XXX−XXX

Letter

ACS Applied Materials & Interfaces

Figure 1. Preparation of MWCNT-PDA hybrid fibers (MWCNT@PDA). Step 1: coating of DA monomers on MWCNT sheets (MWCNT@DA). Step 2: in situ photopolymerization of DA under UV light irradiation to afford MWCNT@PDA. Photograph of as-prepared MWCNT@PDA fibers on a flexible plastic surface.

Figure 2. FESEM images of MWCNTs and MWCNT@PDA. (a) Panoramic view of pristine MWCNT fibers. (b) High-resolution image of MWCNT fibers. (c) Panoramic view of MWCNT@PDA after complete polymerization. (d) High-resolution image of MWCNT@PDA.

(2) the self-assembly of alkyl chains on the surface of MWCNTs, and (3) the conductivity and presence of functional groups on the resultant PDA to facilitate the ion intercalation. Using the obtained three-component hybrid-based electrode, we observed a synergistic effect of the capacitance enhancement as compared to graphite-MWCNT and graphite-PDA electrodes. In fact, galvanostatic charge/discharge (GCD) curves of pure graphite and graphite-MWCNTs were similar, indicating that aligned MWCNT sheets alone cannot significantly

(Figure 1). A diacetylene (DA) monomer, 10,12-pentacosadiynoic acid, was spin-coated uniformly on the surface of MWCNTs and then polymerized in situ under 254 nm UV light irradiation (Scheme S1). Unlike typical conducting polymers used in composite capacitors, the DA monomer could be photopolymerized easily in the solid state without incorporating binders or initiators that hinder electrochemical performance.16,17,27 The selection of this monomer was mainly due to following aspects: (1) its ease of photopolymerization, B


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carried out to confirm the hydrophilicity. Photographs of a drop of water on the surface of MWCNTs and MWCNT@PDA are shown in Figure S8. The water CA on pristine MWCNTs is (150.4 ± 2)°, whereas that on MWCNT@PDA recedes to (79 ± 3)°. The CA measurements clearly show a hydrophilic change of the MWCNT surface after the PDA functionalization. A uniform surface modification for anchoring functional groups on MWCNTs was thus achieved via the photopolymerization of DA. Electrochemical properties of all the prepared electrodes using bare MWCNT sheets, PDA, and MWCNT@PDA hybrid were then investigated in detail. Cyclic voltammogram (CV) studies were conducted to evaluate their electrochemical behavior at different potential window ranges from 0 to 1 and from 0 to 1.2 V. All the systems exhibited a similar (quasi-) rectangular shape within the tested potential window, which is the characteristic of supercapacitors at 1.2 V (Figure 4a). Among the three electrodes, MWCNT@ PDA revealed the largest CV loop, indicating its superiority as a supercapacitor over PDA and bare MWCNTs. The CV curves maintained a quasi-rectangular shape even at a high scan rate of 100 mV s−1, suggesting stable supercapacitor performance of the MWCNT@PDA hybrid (Figure 4b). The specific capacitance (C) of a supercapacitor was calculated from the CV curve according to the following eq 1.30

improve the capacitance. It was proposed that the high capacitance of the hybrid-based electrode was originated from the synergistic effect of large active surface area of MWCNTs and uniform surface coating of PDA (rich in functional groups) over underlying MWCNT sheets. Morphological analysis of the synthesized hybrid MWCNT@ PDA was carried out by electron microscopy micrographs. The experimental process and characterization details are provided in the Supporting Information. A high degree of the alignment in the transferred MWCNT sheets is evident from the field emission scanning electron microscopy (FESEM) images (Figure 2a, b). Contrary to solution processed MWCNTs, charges do not have to cross boundaries in the MWCNT sheets used in this work, where the MWCNT sheets have an electrical conductivity in the range of 102−103 S cm−1.29,30 FESEM studies of the MWCNT@PDA hybrid on graphite substrate revealed a uniform coating of the MWCNT sheets with PDA (Figure 2c). The structure resembled a porous architecture with voids between the MWCNT@PDA bundles, aligned in a horizontal direction (Figure 2d). In the case of only PDA on graphite paper, it was observed that the polymer segments were formed in random orientations without voids, which were evident from the SEM image (Figure S2). Thus, the photopolymerization of DA on MWCNT sheets led to a hybrid structure with functionalized surface and larger surface area in comparison to pristine MWCNT sheets or only PDA. The surface modification of MWCNTs was further investigated using optical microscope images (Figure S3), powder X-ray diffraction (Figure S4), Raman spectroscopy (Figure 3 and Figure S5), and FT-IR spectroscopy (Figure S6).

C=

1 2mvΔV

∫V

V2

1

I(V )dV

(1)

where m is the mass (g) of the electroactive materials in the electrode, ν is the potential scan rate (mV s−1), ΔV is the potential difference (V), I(V) is the response current density (A), and V is the potential (V). It was calculated that the MWCNT@PDA electrode gave a specific capacitance of 396.7 F g−1, whereas bare MWCNTs and PDA showed capacitance values of 263.2 F g−1 and 326.2 F g−1 in the 0−1.2 V potential window, respectively. The increase in the specific capacitance for the MWCNT@PDA electrode could be attributed to the enhanced active surface area brought by the surface functionalization of PDA on MWCNTs.6 Specifically, the rise in the specific capacitance occurs probably due to the following reasons. (1) As DA polymerizes on the surface of MWCNTs, ions from the electrolyte are exposed to larger PDA surface when compared to the PDA-graphite electrode. (2) The MWCNT@PDA structure possesses better electric transportation property, which further facilitates the ion transport from the electrolyte. The superior conductive performance of the MWCNT@PDA hybrid was also confirmed through impedance measurements (Figure S9). The GCD performance of three different electrodes was evaluated at different current densities and compared at 3 A g−1. The specific capacitance (C) of supercapacitors was determined by the GCD technique employing the following eq 2.

Figure 3. (a) Raman spectra of MWCNTs and MWCNT@PDA. Raman mapping of (b) MWCNTs, (c) MWCNT@PDA, and (d) overlay of b and c. Laser excitation at 633.8 nm was used for all acquisitions. The scale bar corresponds to 10 μm.

The Raman spectra of MWCNTs exhibited a combination of characteristic peaks, i.e., the G band at 1580 cm−1, D band at 1345 cm−1, and 2D band at 2700 cm−1. The photopolymerization of DA monomers was confirmed by intense peaks around 1450 and 2080 cm−1, corresponding to vinylic and acetylenic C−C bonds in the PDA backbone. FT-IR spectrum of MWCNT@PDA shows characteristic peaks from PDA. The surface of MWCNT@PDA was expected to be hydrophilic owing to the presence of − COOH groups from PDA side chains. Contact angle (CA) measurements of MWCNTs and MWCNT@PDA on the glass surface were

C = I /m(ΔV /Δt )

(2)

where I refers to the applied current, and ΔV/Δt is the slope of the discharge curve of the GCD profile. Figure 4c shows the GCD patterns of bare MWCNT, PDA, and MWCNT@PDA electrodes obtained in the potential window of 0−1.2 V at a current density of 3 A g−1. MWCNT@PDA electrode based cell system showed high specific capacitance than the other two samples. The calculated specific capacitance of bare MWCNTs, PDA, and the MWCNT@PDA is 500, 666.7, and 1111 F g−1 in a potential window of 0−1.2 V at 1 A g−1, respectively. C


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Figure 4. (a) Comparison of CV curves from PDA, pristine MWCNT, and MWCNT@PDA electrodes. (b) CV curves of the MWCNT@PDA electrode at different scan rates. (c) Typical GCD curves of PDA, MWCNT, and MWCNT@PDA electrodes obtained at 3 A g−1. (d) Capacitance variation of the MWCNT@PDA electrode after 7000 charge/discharge cycles. The potential window is 0−1.2 V for all plots.

The capacitance may be changed upon varying the contents of MWCNTs and PDA. MWCNTs with different weights embedded in graphite and hybrid were evaluated. The specific capacitance of PDA-based electrode could not be obviously changed, even if there was an increase in the content of PDA. On the other hand, the increase in the specific weight of the hybrid led to the capacitance enhancement, but the capacitance still remained proportional by following the same trend as shown in Figure 4c. As evident from the plots (Figure 4c), MWCNT@PDA showed significantly better performance in comparison to the control groups. Moreover, it presented an excellent stability (ca. 95%) after 7000 charge/discharge cycles at a current density of 2 A g−1 (Figure 4d). Similarly, electrochemical tests were carried out in the potential window of 0−1.0 V. Figure S10a shows the obtained CV curves of the MWCNT@PDA electrode at 0 to 1 V. The MWCNT@PDA hybrid presented a specific capacity of 164.7 F g−1 at 20 mV s−1. The CV plots obtained at different scan rates maintained the quasi-rectangular shape, indicating stable performance of the hybrid (Figure S10b). The GCD profiles of the prepared electrodes were also compared (Figure S10c). The calculated specific capacitance of bare MWCNTs, PDA, and MWCNT@PDA is 107.2, 160.2, and 316.2 F g−1 in a potential window of 0−1 V, respectively. The variation in the specific capacitance is mainly due to the IR drop of the electrode systems related to the conductivity of the samples as well as the combined effect of electric double-layer capacitors and pseudocapacitive charge storage behavior of the MWCNT@PDA electrode. Among the studied electrodes at 0−1.0 V voltage window, MWCNT@PDA showed the lowest

dropping potential of 0.028 V. For bare MWCNTs and PDA, the dropping potential was measured as about 0.04 and 0.10 V, respectively. GCD curves of the MWCNT@PDA electrode tested at different current densities are shown in Figure S11. The obtained charge/discharge behavior resembles the result under 0 to 1 V voltage window. It was noted that increasing the current rate could vary the dropping potential, mainly due to high polarization of the current response. To avoid the overestimation of the specific capacitance, the slope was calculated from the potential after the IR drop. Among the studied electrodes in the 0−1.2 V potential window, MWCNT@PDA showed the lowest dropping potential of about 0.04 V. For bare MWCNTs and PDA, the dropping potential was about 0.07 and 0.18 V, respectively. Table S1 summarizes the comparison of specific capacitance values computed from CV curves and GCD curves. It is obvious from the table that the capacitance values calculated from GCD curves were higher than that computed from CV curves. A possible nonlinear behavior of the electrodes is visible in GCD curves of the electrodes. In addition, the MWCNT@PDA hybrid exhibited better supercapacitor behavior than bare MWCNTs and PDA. By analyzing the nature of GCD curves, it looks that the MWCNT@PDA hybrid behaves more like a pseudocapacitor. The nonlinear proportionality of voltage and time highlights the pseudocapacitive behavior of the MWCNT@PDA hybrid owing to the PDA coating. On the other hand, the curves also present slight linear triangular proportionality, which could be attributed to the electrodouble-layer capacitive behavior of MWCNTs. Nevertheless, the major performance of the MWCNT@PDA electrode is D


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(4) Wang, A.; Cheng, Y.; Zhang, H.; Hou, Y.; Wang, Y.; Liu, J. Effect of Multi-Walled Carbon nanotubes and Conducting Polymer on Capacitance of Mesoporous Carbon Electrode. J. Nanosci. Nanotechnol. 2014, 14, 7015−7021. (5) Chen, T.; Peng, H.; Durstock, M.; Dai, L. High Performance Transparent and Stretchable All-Solid Supercapacitors based on Highly Aligned Carbon Nanotube Sheets. Sci. Rep. 2014, 4, 3612. (6) Yang, Z.; Deng, J.; Ren, J.; Peng, H. A Highly Stretchable, FiberShaped Supercapacitor. Angew. Chem., Int. Ed. 2013, 52, 13453− 13457. (7) Xu, P.; Gu, T.; Cao, Z.; Wei, B.; Yu, J.; Li, F.; Byun, J.; Lu, W.; Li, Q.; Chou, T.-W. Carbon Nanotube Fiber Based Stretchable WireShaped Supercapacitors. Adv. Energy Mater. 2014, 4, 1300759. (8) Chen, J.; Jia, C.; Wan, Z. Novel Hybrid Nanocomposite Based on Poly(3,4-Ethylenedioxythiophene)/Multiwalled Carbon Nanotubes/ Graphene as Electrode Materials for Supercapacitors. Synth. Met. 2014, 189, 69−76. (9) Fan, H.; Zhao, N.; Wang, H.; Xu, J.; Pan, F. 3D Conductive Network-based Free-Standing PANI-RGO-MWNTs Hybrid Film for High-Performance Flexible Supercapacitor. J. Mater. Chem. A 2014, 2, 12340−12347. (10) Notarianni, M.; Liu, J.; Mirri, F.; Pasquali, M.; Motta, N. Graphene-Based Supercapacitor with Carbon Nanotube Film as Highly Efficient Current Collector. Nanotechnology 2014, 25, 435405. (11) Chen, T.; Hao, R.; Peng, H.; Dai, L. High-Performance, Stretchable, Wire-Shaped Supercapacitors. Angew. Chem., Int. Ed. 2014, 54, 618−622. (12) Ania, C. O.; Khomenko, V.; Raymundo-Piñero, E.; Parra, J. B.; Béguin. The Large Electrochemical Capacitance of Microporous Doped Carbon Obtained by Using a Zeolite Template. Adv. Funct. Mater. 2007, 17, 1828−1836. (13) Futaba, D. N.; Hata, K.; Yamada, T.; Hiraoka, T.; Hayamizu, Y.; Kakudate, Y.; Tanaike, O.; Hatori, H.; Yumura, M.; Iijima, S. ShapeEngineerable and Highly Densely Packed Single-Walled Carbon Nanotubes and Their Application as Super-Capacitor Electrodes. Nat. Mater. 2006, 5, 987−994. (14) Numao, S.; Judai, K.; Nishijo, J.; Mizuuchi, K.; Nishi, N. Synthesis and Characterization of Mesoporous Carbon NanoDendrites with Graphitic Ultra-Thin Walls and Their Application to Supercapacitor Electrodes. Carbon 2009, 47, 306−312. (15) Zhang, K.; Zhang, L. L.; Zhao, X. S.; Wu, J. Graphene/ Polyaniline Nanofiber Composites as Supercapacitor Electrodes. Chem. Mater. 2010, 22, 1392−1401. (16) Raymundo-Piñero, E.; Cadek, M.; Béguin, F. Tuning Carbon Materials for Supercapacitors by Direct Pyrolysis of Seaweeds. Adv. Funct. Mater. 2009, 19, 1032−1039. (17) Wang, Y.-Y.; Li, H.-Q.; Xia, Y.-Y. Ordered Whiskerlite Polyaniline Grown on the Surface of Mesoporous Carbon and Its Electrochemical Capacitance Performance. Adv. Mater. 2006, 18, 2619−2623. (18) Zhang, M.; Atkinson, K. R.; Baughman, R. H. Multifunctional Carbon Nanotube Yarns by Downsizing an Ancient Technology. Science 2004, 306, 1358−1361. (19) Zhang, M.; Fang, S.; Zakihidov, A. A.; Lee, B. S.; Aleiv, A. E.; Williams, C. D.; Atkinson, K. R.; Baughman, R. H. Strong, Transparent, Multifunctional, Carbon Nanotube Sheets. Science 2005, 309, 1215−1219. (20) Zhang, X.; Li, Q.; Holesinger, T. G.; Arendt, P. N.; Huang, J.; Kirven, P. D.; Clapp, T. G.; DePaula, R. F.; Liao, X.; Zhao, Y.; Zheng, L.; Peterson, D. E.; Zhu, Y. Ultrastrong, Stiff, and Lightweight CarbonNanotube Fibers. Adv. Mater. 2007, 19, 4198−4201. (21) Li, Q. W.; Li, Y.; Zhang, X. F.; Chikkannanavar, S. B.; Zhao, Y. H.; Dangelewicz, A. M.; Zheng, L. X.; Doorn, S. K.; Jia, Q. X.; Peterson, D. E.; Arendt, P. N.; Zhu, Y. T. Structure-Dependent Electrical Properties of Carbon Nanotube Fibers. Adv. Mater. 2007, 19, 3358−3363. (22) Zheng, L.; Sun, G.; Zhan, Z. Tuning Array Morphology for High-Strength Carbon-Nanotube Fibers. Small 2010, 6, 132−137.

governed by the pseudocapacitance. This synergistic mechanism leads to highly stable performance of the MWCNT@PDA electrode. In conclusion, we have demonstrated a noncovalent selfassembly method of PDA cloaking on the surface of MWCNTs by in situ photopolymerization to yield the MWCNT@PDA hybrid. The noncovalent nature of functionalization preserves high inherent conductivity of the aligned MWCNTs, and at the same time, increases the active surface area of MWCNT@PDAbased electrode, both of which are desirable for efficient supercapacitors. The MWCNT@PDA-based supercapacitor exhibited a specific capacitance of 1111 F g−1 at a current density of 3 A g−1 and ca. 95% stability after 7000 charge/ discharge cycles. Easy fabrication of the MWCNT@PDA hybrid combined with its excellent cyclic stability and flexibility makes it a suitable candidate for future wearable electronics applications.

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ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acsami.6b12171. Detailed preparation of MWCNT fibers, photopolymerization, FESEM image, optical microscope images, powder X-ray diffraction patterns, Raman spectrum, FT-IR spectra, contact angle measurements, Nyquist plots, and CV/GCD curves at 0−1 V (PDF)

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AUTHOR INFORMATION

Corresponding Authors

*E-mail: [email protected]. *E-mail: [email protected]. ORCID

Yanli Zhao: 0000-0002-9231-8360 Author Contributions †

M.U. and R.V.H. contributed equally to this work. The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript. Notes

The authors declare no competing financial interest.

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ACKNOWLEDGMENTS S.S. and Y.L.Z. thank the Singapore Academic Research Fund (AcFR) Tier 1 (Grant RG112/15). R.V.H. and J.Y. acknowledge partial financial support of this work from the Ministry of Education of Singapore (Grant RG15/13). N. D. acknowledges the Louis Stokes South Carolina Alliance for Minority Participation for funding research work in Singapore.

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REFERENCES

(1) Aricò, A. S.; Bruce, P.; Scrosati, B.; Tarascon, J.; van Schalkwijk, W. Nanostructured Materials for Advanced Energy Conversion and Storage Devices. Nat. Mater. 2005, 4, 366−377. (2) Xie, X.; Gao, L.; Sun, J.; Liu, Y.; Kajiura, H.; Li, Y.; Noda, K. The Effect of Electro-Degradation Processing on Microstructure of Polyaniline/Single Wall Carbon Nanotube Composite Films. Carbon 2008, 46, 1145−1151. (3) Choi, N.; Chen, Z.; Freunberger, S. A.; Ji, X.; Sun, Y.; Amine, K.; Yushin, G.; Nazar, L. F.; Cho, J.; Bruce, P. G. Challenges Facing Lithium Batteries and Electrical Double-Layer Capacitors. Angew. Chem., Int. Ed. 2012, 51, 9994−10024. E


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ACS Applied Materials & Interfaces (23) Jiang, K.; Wang, J.; Li, Q.; Liu, L.; Liu, C.; Fan, S. Superaligned Carbon Nanotube Arrays, Films, and Yarns: A Road to Applications. Adv. Mater. 2011, 23, 1154−1161. (24) Lima, M. D.; Fang, S.; Lepŕo, X.; Lewis, C.; Ovalle-Robles, R.; Carretero-González, J.; Castillo-Martínez, E.; Kozlov, M. E.; Oh, J.; Rawat, N.; Haines, C. S.; Haque, M. H.; Aare, V.; Stoughton, S.; Zakhidov, A. A.; Baughman, R. H. Biscrolling Nanotube Sheets and Gunctional Guests into Yarns. Science 2011, 331, 51−55. (25) Sun, G.; Zhang, Y.; Zheng, L. Fabrication of Microscale Carbon Nanotube Fibers. J. Nanomater. 2012, 2012, 506209. (26) Ren, J.; Chen, C.; Chen, X.; Cai, Z.; Qiu, L.; Wang, Y.; Zhu, X.; Peng, H. Twisted Carbon Nanotube Fibers for Both Wire-Shaped Micro-Supercapacitor and Micro-Battery. Adv. Mater. 2013, 25, 1155− 1159. (27) Sun, G.; Zheng, L.; Zhan, Z.; Jiang, C.; Hansen, R. V.; Khor, Y.; Pang, J. H. L. Highly Reliable Carbon Nanotube-Based Composite Fibers Cross-Linked by a 3D Polymer Network. Adv. Eng. Mater. 2014, 16, 961−965. (28) Sreejith, S.; Hansen, R. V.; Joshi, H.; Kutty, R. G.; Liu, Z.; Zheng, L.; Yang, J.; Zhao, Y. Quantum Dot Decorated Aligned Carbon Nanotube Bundles for a Performance Enhanced Photoswitch. Nanoscale 2016, 8, 8547−8552. (29) Hansen, R. V.; Huang, M.; Zhan, Z.; Sun, G.; Yang, J.; Zheng, L. On the Study of Electrochromism in Multiwalled Carbon NanotubePolydicaetylene Composites. Carbon 2015, 90, 222−230. (30) Wang, H.; Casalongue, H. S.; Liang, Y.; Dai, H. Ni(OH)2 Nanoplates Grown on Graphene as Advanced Electrochemical Pseudocapacitor Materials. J. Am. Chem. Soc. 2010, 132, 7472−7477.

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Photopolymerization of Diacetylene on Aligned Multiwall Carbon

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