Lu2@C82 Nanorods with Enhanced Photoluminescence and

Aug 10, 2017 - Pan, Bao, Yu, Fang, Xie, Akasaka, and Lu. 2018 12 (2), pp ... Shen, Bao, Wu, Pan, Zhao, Fang, Xie, Jin, Peng, Li, and Lu. 2017 139 (29)...
0 downloads 0 Views 634KB Size
Subscriber access provided by Columbia University Libraries

Article

Lu2@C82 nanorods with enhanced photoluminescence and photoelectrochemical properties Wangqiang Shen, Li Zhang, ShuShu Zheng, Yun-Peng Xie, and Xing Lu ACS Appl. Mater. Interfaces, Just Accepted Manuscript • DOI: 10.1021/acsami.7b05180 • Publication Date (Web): 10 Aug 2017 Downloaded from http://pubs.acs.org on August 10, 2017

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 free 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 accessible to all readers and 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.

ACS Applied Materials & Interfaces 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 18

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 Materials & Interfaces

Lu2@C82

nanorods

with

enhanced

photo-

luminescence and photoelectrochemical properties Wangqiang Shen‡, Li Zhang‡, Shushu Zheng, Yunpeng Xie, Xing Lu* State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology (HUST), Wuhan 430074, P. R. China.

ABSTRACT: One-dimensional (1D) single-crystalline hexagonal nanorods of Lu2@C3v(8)-C82 were prepared for the first time using the liquid-liquid interface precipitation method (LLIP) from the interfaces between carbon disulfide (CS2) and isopropyl alcohol (IPA). The length of the nanorods can be readily controlled by varying the concentration of the Lu2@C82 solution in addition to the volume ratio of CS2 to IPA. The latter factor also exhibits a significant influence on the morphology of the crystals. The crystalline structure of the nanorods has been investigated by XRD and selected area electron diffraction (SAED), suggesting a face-centered cubic structure. Photoluminescence of the Lu2@C82 nanorods shows a remarkable enhancement as compared to that of pristine Lu2@C82 powder because of the high crystallinity. Furthermore, we have investigated the photoelectrochemical properties of Lu2@C82 nanorods, proving their potential applications as photodetectors.

KEYWORDS: Lu2@C82, LLIP, nanorods, photoluminescence, photodetector

ACS Paragon Plus Environment 1

ACS Applied Materials & Interfaces

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 18

Introduction Endohedral metallofullerenes (EMFs), a new class of hybrid molecules formed by the encapsulation of metallic species inside fullerene cages, exhibit unique properties because of the presence of metals and their hybridization effect via electron transfer.1 Consequently, EMFs show prospects in photoelectric and photoluminescence applications. To this end, ordered nano/microstructures are normally necessary to achieve the corresponding applications. However, investigations of nanostructures of EMFs and their applications are quite limited up to now.2,3 For mono-EMFs which contain only one metal atom, Wang et al. fabricated nanotubes of Sc@C82 with an anodic aluminum oxide template followed by electrochemical deposition in 2005.4 In 2008, Tsuchiya et al. obtained needle-like structures of La@C82(Ad) with a liquidliquid interface precipitation method (LLIP), which showed a p-type field-effect transistor (FET) property.2 For cluster-EMFs (metallic clusters encapsulated in fullerenes), Sc3N@C80 nanorods and nanosheets were first prepared by Wakahara et al. in 20105 and then in 2014, Xu et al. reported the preparation of three-dimensional (3D) nanostructures of Sc3N@C80 via a microwave-assisted LLIP method6. Although several kinds of EMF-nanostructures and their properties have been reported,7,8 morphologies and photoluminescence and photoelectrochemical properties of di-EMFs (EMFs with two metal atoms) have barely been studied. Meanwhile, one-dimensional (1D) nanostructures, such as nanowires, nanofibers, nanorods, nanotubes have attracted extensive interest because of their unique advantages over bulk materials such as short path lengths for ion insertion/extraction and electronic transport in addition to very large surface to volume ratio in the field of electronic aplication.9-12 Therefore, it is of vital importance to synthesize 1D nanostructures of EMFs so as to achieve their future applications.

ACS Paragon Plus Environment 2

Page 3 of 18

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 Materials & Interfaces

Herein, we report for the first time the preparation and characterization of 1D nanostructures of Lu2@C3v(8)-C82 by the LLIP method. The size of the prepared nanorods can be controlled by varying the concentration of the Lu2@C82 solution and the volume ratio of good/poor (CS2/IPA) solvents. With the unique nanorods in hand, we have been able to characterize the photoluminescence properties of di-EMFs nanostructures for the first time. As a result of their high crystallinity, Lu2@C82 nanorods display remarkably enhanced photoluminescence as compared to Lu2@C82 powder. Finally, it is demonstrated that these well-ordered Lu2@C82 nanorods exhibit excellent photoconductive properties, with spectral responses covering the ultraviolet to visible region, highlighting their future applications as optical sensors. Experimental section Materials Lu2@C82 was synthesized by a direct current arc-discharge method.13 Then Lu2@C3v(8)-C82 with a high purity (>99%) was isolated by HPLC (see Supporting Information for its mass spectrum (Figure S1), UV-Vis-NIR spectrum (Figure S2) and an ORTEP drawing of Lu2@C3v(8)-C82 (Figure S3)). All solvents were used as received without further purification. Growth of Lu2@C82 Crystals Lu2@C82 nanorods were prepared by the LLIP method.14 Typically, a varying volume of IPA, which serves as the poor solvent, was slowly added into 1mL Lu2@C82 solution in CS2 of different concentrations. The crystals formed after the mixture was kept at room temperature for 24 h without any further agitation. Results and discussion

ACS Paragon Plus Environment 3

ACS Applied Materials & Interfaces

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 4 of 18

Effect of Lu2@C82 concentration on the morphology of the nanostructures

Figure 1. SEM images of Lu2@C82 nanorods prepared by the LLIP method under different concentrations of Lu2@C82 in CS2. (a) and (b) 1.2 mg/mL, (c) 0.8 mg/mL, (d) 0.4 mg/mL. It has been known that the concentration of solution usually exhibits an influence on the morphology of the crystal structures. Accordingly, we changed the concentration of Lu2@C82 in CS2 from 1.2 to 0.4 mg/mL, but fixed the volume ratio of CS2 to IPA as 1:4. The results show that hexagonal rod-like Lu2@C82 nanostructures precipitated with an average diameter of 450 nm and an average length of 16 µm (Figure 1a, 1b). With the decreasing of the concentration, the average length of the Lu2@C82 nanorods gradually increase from 16 to 35 µm (Figure 1), while the diameter of the Lu2@C82 nanorods remains unchanged with an average size of 450 nm.

ACS Paragon Plus Environment 4

Page 5 of 18

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 Materials & Interfaces

This phenomenon can be explained as follows. The nucleation occurs immediately when the poor solvent IPA is added into the solution of Lu2@C82/CS2. The growth direction of the Lu2@C82 rods largely follows along the length direction due to the intermolecular π-π interactions of the Lu2@C82 molecules.15,16 In the case of a higher concentration, more nucleation sites and larger concentration depletion of Lu2@C82 are expected.15,17 Accordingly, increasing Lu2@C82 concentration in the stock solution reduces the duration of the precipitation stage, resulting in a shorter growth process of the nanorods.18 As a result, shorter Lu2@C82 nanorods are formed under a higher concentration and vice versa. In particular, when the concentration is decreased to 0.4 mg/mL, much longer nanorods with an average length over 34 µm are obtained (Figure S4) but even lower concentration did not give any precipitation during the LLIP process. These results indicate that the length of the Lu2@C82 nanorods can be simply controlled by changing the concentration of the Lu2@C82 solution. Effect of good/poor solvents volume ratio on the morphology of Lu2@C82 structures

ACS Paragon Plus Environment 5

ACS Applied Materials & Interfaces

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 6 of 18

Figure 2. SEM images of Lu2@C82 nanostructures grown under different volume ratios of Lu2@C82/CS2 to IPA. (a): 1:4; (b). 1:10; (c): 1:14; (d): 1:17. To further explore the effect of the volume ratio of good/poor solvents on the morphology of Lu2@C82 structures, we fix the concentration of the solution of Lu2@C82 in CS2 as 1.2 mg/mL and vary CS2/IPA volume ratio from 1:4 to 1:17. With the increasing of IPA volume, the length of Lu2@C82 nanorods decrease obviously, whereas the average diameter of nanorods approximately keeps constant (Figure 2). According to the classic crystal growth theory, the formation of a crystal can be divided into two stages, namely, nucleation and growth.19 We speculate that increase of IPA volume promotes the number of nuclei, which causes a faster crystalline process, resulting in a decrease of the length of Lu2@C82 nanorods.18 Besides, a more severe concentration depletion caused by increasing nuclei density with increasing value of IPA volume can be another reason for the length decreasing.16,18

ACS Paragon Plus Environment 6

Page 7 of 18

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 Materials & Interfaces

Selectivity of nanorods formation against other structures

Figure 3. Statistics of the number ratios of nanorods to other structures under different volume ratios of Lu2@C82/CS2 to IPA. As exhibited in Figure 1 and Figure 2, it is very interesting that Lu2@C82 microsheets were also produced together with Lu2@C82 nanorods in our experiments. When the concentration of Lu2@C82 is 1.2 mg/mL with the CS2/IPA (v/v) ratio being set as 1:4, the width of microsheets is found to be in the range from 3 to 10 µm (Figure 2b). However, both the size of the microsheets and the number ratio to the total nanostructures exhibit no obvious change when the concentration of Lu2@C82 decreased from 1.2 to 0.4 mg/mL when the volume ratio of CS2/IPA is kept as 1:4 (Figure 1). To our surprise, with the increasing of IPA volume, the content of microsheets appeared to increase (Figure 2). Furthermore, other morphologies of Lu2@C82 (cubes and polyhedrons) also precipitated along with the gradual increase of IPA volume (Figure S5). The total amounts of both nanorods and other structures are summarized in Table S1 and the number ratio of nanorods to other structures is shown in Figure 3. After nucleation, growth along both the length and the diameter directions takes place and forms side and bottom/up surfaces

ACS Paragon Plus Environment 7

ACS Applied Materials & Interfaces

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 18

simultaneously.16 We believe that the morphology of Lu2@C82 structures highly depends on the number ratio of side to bottom/up surfaces. Lower ratio of Lu2@C82/CS2 solution to IPA leads to a higher number ratio of side surface to the bottom/up surface.19 When the value of CS2/IPA (v/v) decreased to 1:17, the side surfaces become dominant and result in polyhedron structures (Figure 2d). Noteworthily, when the volume ratio (CS2/IPA) decreased from 1:14 to 1:17, the number ratio of rods exhibited a remarkable decrease. Therefore, we speculate that there is a critical value for the selective nanorod-formation against other structures between 1:14 and 1:17. In addition, the bottom/top surfaces of Lu2@C82 nanorods with various facets (Figure S5) suggest the differences in the growth rate of the various directions.20,21 When the volume ratio of IPA is low, the growth along the length direction shows significant dominance and results in rod-like structures. However, with a higher volume ratio of IPA, the high concentration of nuclei would hinder the crystal growth along the length direction, which is the main reason for the formation of the polyhedron structures. Based on the experimental observations mentioned above, we tried to vary the CS2/IPA (v/v) ratio to a very high value in order to prepare pure rod-like structures but did not obtain any precipitation. The reason for the phenomenon can be attributed to that deficiency of IPA content could not induce a sufficient supersaturation of Lu2@C82 because of the high solubility of Lu2@C82 in CS2, and therefore ccould not induce the precipitation of Lu2@C82.

ACS Paragon Plus Environment 8

5

10

15 20 2θ / degree

420 422

410

212 310

002

Intensity / a.u.

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 Materials & Interfaces

111

Page 9 of 18

25

30

Figure 4. X-ray diffraction (XRD) pattern of Lu2@C82 nanorods.

Figure 5. High-resolution transmission electron microscopy (HR-TEM) image and selected area electron diffraction (SAED) pattern (inset) of a Lu2@C82 nanorod. Crystal configuration of Lu2@C82 nanorods The superior uniformity of both size and length distributions of Lu2@C82 nanorods was achieved while the concentration of Lu2@C82/CS2 solution was set at 1.2 mg/mL and the volume ratio of CS2/IPA was tailored to 1:4. In the following studies we will focus merely on this sample.

ACS Paragon Plus Environment 9

ACS Applied Materials & Interfaces

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 10 of 18

An X-ray diffraction (XRD) study was carried out to characterize the structures of the nanorods. Figure 4 shows the corresponding XRD patterns. The peaks can be indexed to (111), (002), (212), (310), (410), (420), and (422) planes which correspond to the face-centered cubic (fcc) structure with lattice parameters of a=b=c=15.2 Å.22 We further used high-resolution transmission electron microscopy (HR-TEM) to investigate the details of the crystal structure. The image (Figure 5) of a Lu2@C82 nanorod shows a clear lattice with the distance between two adjacent planes of 10.70 Å, which can be assigned to the dspacing of the (110) crystalline planes. The SAED pattern reveals the (002), (210), (212) planes with lattice spacing of 7.53, 6.80, and 5.02 Å. These results further confirm our assignment of the fcc structure of the nanorods. Photoluminescence property of the Lu2@C82 nanorods Although photoluminescence (PL) of empty fullerene micro/nanostructures has been widely investigated23–25, the exploration of the photoluminescence of EMFs, particularly di-EMFs, has rarely been reported. Herein, we measured the PL spectra of both Lu2@C82 power and the Lu2@C82 crystals (Figure 6). The PL intensity of the self-assembled Lu2@C82 nanorods shows a remarkable enhancement compared to that of Lu2@C82 powder, which is most probably induced by the high crystallinity of the nanostructures.17,26–29 Meanwhile, the highly ordered arrangement of Lu2@C82 molecules may minimize defects and torsional motions of the Lu2@C82 molecules and hence suppresses nonradiative decay of the excited states to increase the level of radiative exciton recombination.23,27,28,30

ACS Paragon Plus Environment 10

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 Materials & Interfaces

PL intensity / a.u.

Page 11 of 18

Lu2@C82 rods

3k

Lu2@C82 powder

2k

1k

0 600

700

800

Wavelength / nm

900

1000

Figure 6. Photoluminescence spectra of Lu2@C82 powder (black) and Lu2@C82 nanorods (red) recorded at room temperature upon excitation with a 532 nm laser. Photoelectrochemical properties of Lu2@C82 nanorods Previous reports on photoelectrochemical studies of EMFs are quite limited, and only the results of Dy@C82 based on its Langmuir-Blodgett (LB) films and S3N@C80 rods have been reported.15,31 In this work, the photoelectrochemical properties of Lu2@C82 nanorods are explored. As shown in Figure 7, the film of nanorods shows fast photo-responses to each on-off event in both visible and ultraviolet regions. For comparison, the photoelectrochemical properties of Lu2@C82 powder under the same experimental conditions are also measured (Figure S7). It is evident that the photocurrents responding of Lu2@C82 nanorods show an enhancement as compared to that of Lu2@C82 powder under the same conditions, indicating that the charge carrier transport has been promoted in the ordered nanostructures. Accordingly, it is proposed that Lu2@C82 nanostructures show a promise for potential applications as optical sensors.

ACS Paragon Plus Environment 11

ACS Applied Materials & Interfaces

313 nm

2 Photocurrent Density / (mA/cm )

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 12 of 18

20

350 nm

light off

400~780 nm

10

0

light on 0

30

60

90

120 150 180 210 240 270 300

Time / s

Figure 7. Photocurrent responses of film of Lu2@C82 nanorods under UV (313nm, red; 350 nm, green) and visible light (400–780 nm, black) irradiation. Conditions: 0.1 M KCl electrolyte solution under 1 V bias voltage. Conclusions For the first time, single-crystalline 1D Lu2@C82 nanorods was prepared by a LLIP method. The length of the rods can be controlled by varying the concentration of Lu2@C82 and the volume ratio of good to poor solvents. The Lu2@C82 nanorods which have a face-centered cubic structure show a remarkable enhancement of PL as compared with Lu2@C82 powder. Finally, we reveal that Lu2@C82 nanorods show fast photocurrent responses under both visible and UV light irradiation. Thus the 1D nanostructure of Lu2@C82 is demonstrated to facilitate the efficient charge carrier transport and shows potential applications in photoelectric purposes.

ACS Paragon Plus Environment 12

Page 13 of 18

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 Materials & Interfaces

ASSOCIATED CONTENT Supporting Information Characterizations of XRD, PL and the photocurrent tests of Lu2@C82 nanorods or powder; mass spectrum, UV-Vis-NIR spectrum and ORTEP drawing of Lu2@C3v(8)-C82; SEM and optical images of Lu2@C82 nanorods. The statistics of the content of nanorods and other morphologies. Photocurrent responses spectra of the film of Lu2@C82 powder under UV and visible light irradiation. AUTHOR INFORMATION Corresponding Author * E-mail: [email protected]. Author Contributions ‡These authors contributed equally. Notes The authors declare no competing financial interest. ACKNOWLEDGMENT Financial support from The National Thousand Talents Program of China, NSFC (51472095, 51672093, 51602112 and 51602097), Program for Changjiang Scholars and Innovative Research Team in University (IRT1014) and HUST is gratefully acknowledged. We thank the Analytical and Testing Center in Huazhong University of Science and Technology for all related measurements.

ACS Paragon Plus Environment 13

ACS Applied Materials & Interfaces

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 14 of 18

REFERENCES (1)

Lu, X.; Feng, L.; Akasaka, T.; Nagase, S. Current Status and Future Developments of Endohedral Metallofullerenes. Chem. Soc. Rev. 2012, 41, 7723–7760.

(2)

Tsuchiya, T.; Kumashiro, R.; Tanigaki, K.; Matsunaga, Y.; Ishitsuka, M. O.; Wakahara, T.; Maeda, Y.; Takano, Y.; Aoyagi, M.; Akasaka, T.; Liu, M. T. H.; Kato, T.; Suenaga, K.; Jeong, J. S.; Iijima, S.; Kimura, F.; Kimura, T.; Nagase, S. Nanorods of Endohedral Metallofullerene Derivative. J. Am. Chem. Soc. 2008, 130, 450–451.

(3)

Xu, Y.; He, C.; Liu, F.; Jiao, M.; Yang, S. Hybrid Hexagonal Nanorods of Metal Nitride Clusterfullerene and Porphyrin Using a Supramolecular Approach. J. Mater. Chem. 2011, 21, 13538–13545.

(4)

Li, C.-J.; Guo, Y.-G.; Li, B.-S.; Wang, C.-R.; Wan, L.-J.; Bai, C.-L. Template Synthesis of Sc@C82(I) Nanowires and Nanotubes at Room Temperature. Adv. Mater. 2005, 17, 71–73.

(5)

Wakahara, T.; Nemoto, Y.; Xu, M.; Miyazawa, K.; Fujita, D. Preparation of Endohedral Metallofullerene Nanowhiskers and Nanosheets. Carbon. 2010, 48, 3359–3363.

(6)

Xu, Y.; Chen, X.; Liu, F.; Chen, X.; Guo, J.; Yang, S. Ultrasonication-Switched Formation of Dice- and Cubic-Shaped Fullerene Crystals and Their Applications as Catalyst Supports for Methanol Oxidation. Mater. Horiz. 2014, 1, 411–418.

(7)

Miyazaki, T.; Sumii, R.; Umemoto, H.; Okimoto, H.; Sugai, T.; Shinohara, H.; Hino, S. Ultraviolet Photoelectron Spectra of Lu Atoms Encapsulated C2v–C82 Fullerenes. Chem. Phys. Lett. 2013, 555, 222–225.

(8)

Miyamoto, A.; Okimoto, H.; Shinohara, H.; Shibamoto, Y. Development of Water-Soluble Metallofullerenes as X-Ray Contrast Media. Eur. Radiol. 2006, 16, 1050–1053.

ACS Paragon Plus Environment 14

Page 15 of 18

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 Materials & Interfaces

(9)

Wang, Y.; Cao, G. Developments in Nanostructured Cathode Materials for HighPerformance Lithium-Ion Batteries. Adv. Mater. 2008, 20, 2251–2269.

(10) Barth, S.; Hernandez-Ramirez, F.; Holmes, J. D.; Romano-Rodriguez, A. Synthesis and Applications of One-Dimensional Semiconductors. Prog. Mater. Sci. 2010, 55, 563–627. (11) Dasgupta, N. P.; Sun, J.; Liu, C.; Brittman, S.; Andrews, S. C.; Lim, J.; Gao, H.; Yan, R.; Yang,

P.

25th

Anniversary

Article:

Semiconductor

Nanowires



Synthesis,

Characterization, and Applications. Adv. Mater. 2014, 26, 2137–2184. (12) Mai, L.; Tian, X.; Xu, X.; Chang, L.; Xu, L. Nanowire Electrodes for Electrochemical Energy Storage Devices. Chem. Rev. 2014, 114, 11828–11862. (13) W, K.; Lowell D, L.; K, F.; Donald R, H. Solid C60: A New Form of Carbon. Nature. 1990, 347, 354–358. (14) Miyazawa, K.; Kuwasaki, Y.; Obayashi, A.; Kuwabara, M. C60 Nanowhiskers Formed by the Liquid–liquid Interfacial Precipitation Method. J. Mater. Res. 2002, 17, 83–88. (15) Xu, Y.; Guo, J.; Wei, T.; Chen, X.; Yang, Q.; Yang, S. Micron-Sized Hexagonal SingleCrystalline Rods of Metal Nitride Clusterfullerene: Preparation, Characterization, and Photoelectrochemical Application. Nanoscale. 2013, 5, 1993–2001. (16) Wei, L.; Yao, J.; Fu, H. Solvent-Assisted Self-Assembly of Fullerene into Single-Crystal Ultrathin Microribbons as Highly Sensitive UV–Visible Photodetectors. ACS Nano. 2013, 7, 7573–7582. (17) Park, C.; Yoon, E.; Kawano, M.; Joo, T.; Choi, H. C. Self-Crystallization of C70 Cubes and Remarkable Enhancement of Photoluminescence. Angew. Chem. Int. Ed. 2010, 49, 9670–9675.

ACS Paragon Plus Environment 15

ACS Applied Materials & Interfaces

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 16 of 18

(18) Ji, H.-X.; Hu, J.-S.; Tang, Q.-X.; Song, W.-G.; Wang, C.-R.; Hu, W.-P.; Wan, L.-J.; Lee, S.-T. Controllable Preparation of Submicrometer Single-Crystal C60 Rods and Tubes Trough Concentration Depletion at the Surfaces of Seeds. J. Phys. Chem. C. 2007, 111, 10498–10502. (19) Ouyang, J.; Pei, J.; Kuang, Q.; Xie, Z.; Zheng, L. Supersaturation-Controlled Shape Evolution of α-Fe2O3 Nanocrystals and Their Facet-Dependent Catalytic and Sensing Properties. ACS Appl. Mater. Interfaces. 2014, 6, 12505–12514. (20) Wang, D.; Song, C. Controllable Synthesis of ZnO Nanorod and Prism Arrays in a Large Area. J. Phys. Chem. B. 2005, 109, 12697–12700. (21) Zheng, S.; Lu, X. Formation Kinetics and Photoelectrochemical Properties of Crystalline C70 One-Dimensional Microstructures. RSC Adv. 2015, 5, 38202–38208. (22) Shrestha, L. K.; Shrestha, R. G.; Hill, J. P.; Tsuruoka, T.; Ji, Q.; Nishimura, T.; Ariga, K. Surfactant-Triggered Nanoarchitectonics of Fullerene C60 Crystals at a Liquid–Liquid Interface. Langmuir. 2016, 32, 12511–12519. (23) Shin, H. S.; Yoon, S. M.; Tang, Q.; Chon, B.; Joo, T.; Choi, H. C. Highly Selective Synthesis of C60 Disks on Graphite Substrate by a Vapor–Solid Process. Angew. Chem. 2008, 120, 705–708. (24) Zheng, S.; Xu, M.; Lu, X. Facile Method toward Hierarchical Fullerene Architectures with Enhanced Hydrophobicity and Photoluminescence. ACS Appl. Mater. Interfaces. 2015, 7, 20285–20291. (25) Shrestha, L. K.; Hill, J. P.; Tsuruoka, T.; Miyazawa, K.; Ariga, K. Surfactant-Assisted Assembly of Fullerene (C60) Nanorods and Nanotubes Formed at a Liquid–Liquid Interface. Langmuir. 2013, 29, 7195–7202.

ACS Paragon Plus Environment 16

Page 17 of 18

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 Materials & Interfaces

(26) Wang, L.; Liu, B.; Yu, S.; Yao, M.; Liu, D.; Hou, Y.; Cui, T.; Zou, G.; Sundqvist, B.; You, H.; Zhang, D.; Ma, D. Highly Enhanced Luminescence from Single-Crystalline C60·1m-Xylene Nanorods. Chem. Mater. 2006, 18, 4190–4194. (27) Kim, J.; Park, C.; Choi, H. C. Selective Growth of a C70 Crystal in a Mixed Solvent System: From Cube to Tube. Chem. Mater. 2015, 27, 2408–2413. (28) Yao, M.; Fan, X.; Liu, D.; Liu, B.; Wågberg, T. Synthesis of Differently Shaped C70 Nano/Microcrystals by Using Various Aromatic Solvents and Their CrystallinityDependent Photoluminescence. Carbon. 2012, 50, 209–215. (29) Shrestha, L. K.; Shrestha, R. G.; Hill, J. P.; Tsuruoka, T.; Ji, Q.; Nishimura, T.; Ariga, K. Surfactant-Triggered Nanoarchitectonics of Fullerene C60 Crystals at a Liquid–Liquid Interface. Langmuir. 2016, 32, 12511–12519. (30) Riddle, J. A.; Lathrop, S. P.; Bollinger, J. C.; Lee, D. Schiff Base Route to Stackable Pseudo-Triphenylenes:  Stereoelectronic Control of Assembly and Luminescence. J. Am. Chem. Soc. 2006, 128, 10986–10987. (31) Yang, S.; Yang, S. Photoelectrochemistry of Langmuir−Blodgett Films of the Endohedral Metallofullerene Dy@C82 on ITO Electrodes. J. Phys. Chem. B. 2001, 105, 9406–9412.

TOC:

ACS Paragon Plus Environment 17

ACS Applied Materials & Interfaces

Page 18 of 18

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 Paragon Plus Environment 18