Nanoengineered Ultralight Organic Cathode Based on Aromatic

Subscriber access provided by UNIV OF NEW ENGLAND ARMIDALE

Article

Nanoengineered ultralight organic cathode based on aromatic carbonyl compound/graphene aerogel for green lithium and sodium ion batteries Chenpei Yuan, Qiong Wu, Qiang Li, Qian Duan, Yanhui Li, and Hengguo Wang ACS Sustainable Chem. Eng., Just Accepted Manuscript • DOI: 10.1021/ acssuschemeng.8b00500 • Publication Date (Web): 29 May 2018 Downloaded from http://pubs.acs.org on May 29, 2018

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

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

Page 1 of 28 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 Sustainable Chemistry & Engineering

Nanoengineered ultralight organic cathode based on aromatic carbonyl compound/graphene aerogel for green lithium and sodium ion batteries Chenpei Yuan, Qiong Wu, Qiang Li, Qian Duan, Yanhui Li and Heng-guo Wang* School of Materials Science and Engineering, Changchun University of Science and Technology, 7989 Weixing Road, Changchun, 130022, China.. Fax: +86-431-85583176; Tel: +86-431-85583176 E-mail address: [email protected] (H.G. Wang)

1

ACS Paragon Plus Environment

ACS Sustainable Chemistry & Engineering 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 28

Abstract Organic electroactive materials are promising alternatives to traditional inorganic ones in the green organic batteries. However, their practical use is greatly hindered by the intrinsic electrical insulation and the high solubility in electrolyte. Here, we propose an effective strategy to prepare nanoengineered ultralight materials based on organic electroactive material/graphene aerogel in which aromatic carbonyl compound are confined in the three-dimensional hybrid architecture. This special structure has been confirmed by SEM, TEM, FT-IR, XRD, Raman spectra and N2 adsorption/desorption isotherms. Electrochemical investigation further demonstrates that the obtained composite shows high storage capacity of Li+/Na+ ions, long cycling life and good rate capability as cathode materials for Li- and Na-ion batteries (LIBs and SIBs). This enhanced property is attributed to the special structure that significantly improves the conductivity and effectively prohibits the dissolution of active material, but also affords good Li+/Na+ ions accessibility to the organic electroactive materials and shortens the Li+/Na+ ions diffusion length. This work can be further extended to prepare various electrodes based on organic materials for energy storage application. Keywords:

Organic

electrode,

Graphene

aerogel,

Lithium/sodium ion batteries.

2


Carbonyl

compound,

Page 3 of 28 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


Introduction Over the past several decades, energy crisis and environmental degradation have become the top concerns, which promote scientists to search an efficient and clean power source.1-2 Among all the explorations, the rechargeable batteries including Liand Na-ion batteries (LIBs and SIBs) have achieved large successes in view of their high energy density, high efficiency and good cycle stability, which are recognized as the next generation of main energy to reduce the consumption of fossil fuels and the CO2 emission.3-8 However, the traditional LIBs/SIBs cathode materials conventionally used transition metal oxides are restricted by their theoretical specific capacity.9-13 In addition, these materials not only cause the cost and environmental issues resulted from the consumption of energy and mineral resources, but also exist security issues when the battery overcharged.14-15 Thus, there is an urgent to search environmentally friendly and high-performance cathode materials for LIBs and SIBs. Recently, organic cathode materials have shown great promise for LIBSs/SIBs due to their unparalleled advantages, including controllable structure design, easy recycling feature and availability from abundant/renewable biomass.16-21 Especially, the conjugated carbonyl compounds are outstanding candidates as high-performance electrode materials due to their structural diversity, high storage capacity and fast-redox ability.22-26 Nevertheless, these materials suffer from fast capacity decay and poor rate capability due to the severe solubility in electrolyte and low electronic conductivity. Fortunately, recent progresses have demonstrated that incorporating organic materials into highly conductive carbon matrixes can provide the nano-confinement effect, which not only improves their conductivity, but also overcomes the solubility in electrolyte.27-33 Therefore, it is intriguing to search an effective conductive carbon matrix to integrate the conjugated carbonyl compounds. 3



Graphene aerogel, a novel kind of highly porous and ultralight material, is recognized as potential application in the fields of energy storage.34-36 These advantageous properties of high conductivity, large surface area and chemical stability make it possible to be very suitable matrix. Therefore, it seems to be the most applicable strategy to fabricate the ultralight organic materials/graphene aerogel with compatible three-dimensional (3D) porous structure in which organic materials are nano-confined. However, little study on nanoengineered ultralight organic materials/graphene aerogel as cathode materials for LIBs and SIBs has been achieved. In this paper, we proposed an effective and intriguing strategy, that is, a one-step solvothermal process, to fabricate the organic aromatic carbonyl compound/graphene aerogel as the cathode material for LIBs and SIBs. As a representative example of aromatic carbonyl compounds, 3,4,9,10-perylene-tetracarboxylicacid-dianhydride (PTCDA, known as “red 224”) is a red color pigment with a aromatic core and two electroactive conjugated anhydride groups. Thereinto, a stable composite structure could be formed by the π-π interactions between the aromatic core and graphene, and the conjugated anhydride groups are electroactive for Li+/Na+ ions. As expected, the PTCDA/graphene aerogel (PGC) as the cathode material for LIBs can display a high initial capacity of 202.2 mAh g-1 at a current density of 50 mA g-1, long cycle performance without any decay after 200 cycles and excellent rate performance (64 mAh g-1 even at 2000 mA g-1). Moreover, the PGC can also display high initial capacity of ~98 mAh g-1 at 25 mA g-1 and good cycle performance with capacity retention of 90% after 100 cycles as the cathode material for SIBs. Experimental Preparation of PTCDA/graphene composite (PGC) The modified Hummers method was used to prepare Graphene oxide (GO).37 And 4


Page 4 of 28

Page 5 of 28 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


the one-step solvothermal process was used to prepare the PGC. In a typical procedure, different amounts (20, 40, and 60 mg) of PTCDA were dispersed in 40 mL GO aqueous solution (2 mg mL-1). After intensely sustained sonication for 30 min, the resulting mixture solution was added in a 50 mL Teflon autoclave. After treating at 180 °C for 24 h, the Teflon autoclave was cooled, subsequently the as-obtained hydrogel was obtained and then freeze-dried in a freeze drying machine. Herein, different amounts of PTCDA were dispersed in GO aqueous solution, which are denoted here as PGC20, PGC40 and PGC60. Electrochemical measurements Two electrode coin-type cells (CR2025) were used to evaluate electrochemical experiments. Typically, active material (PGCs or PTCDA, 80%),

binder

(polyvinylidene fluoride, PVDF, 10%) and conductive material (acetylene black, 10%) were formed a slurry by using N-methyl-2-pyrrolidinone (NMP). Then, the slurry was spread on an aluminum foil, which was finally dried at 80℃ in a vacuum for 8 h. For LIB fabrication, 1M LiPF6 in ethylene carbonate/dimethyl carbonate (EC/DMC 1:1 Vol%) was used as the electrolyte and Li foil as the counter electrode. For SIB fabrication, 1 M NaPF6 in EC/DMC (1:1 Vol%) was used as the electrolyte and Na foil as the counter electrode. For full cell fabrication, the anode was prepared through casting a slurry containing graphite (80%), acetylene black (10%), and PVDF (10%) in NMP on copper foil. Before assembling full cell, this anode was activated in half cells for five cycles. The mass ratios of graphite to PGCs were about 1:5 and the mass of cathode was used to calculate the corresponding data of full cells. Results and discussion In order to obtain nanoengineered ultralight materials in which aromatic carbonyl compound are confined in the 3D hybrid architecture, hydrothermal reduction method 5



is adopted, as illustrated in Figure 1. Firstly, PTCDA, a representative example of organic aromatic carbonyl compound, is dispersed into GO aqueous solution under continuous string and sonication to form homogenization solution. Then, the mixture undergoes the hydrothermal reaction and reduced under high temperature, during which GO is self-assembled into reduced graphene hydrogel accompanied by the incorporation of the PTCDA particles. Finally, the graphene aerogel wrapped PTCDA particle is obtained after freeze-drying. It is well known that the aerogel shows ultralight feature (inset in Figure 2a), which is beneficial to the composite as cathode materials for LIBs/SIBs. SEM images are firstly employed to investigate the morphology features of the PGCs and pristine PTCDA. As shown in Figure S1, the pristine PTCDA shows rod-like particles resulted from the spontaneous stacking of molecules. Interestingly, PGC40 displays the 3D porous structure (Figure 2a), which is beneficial for electrolyte penetration and ion transportation. From the side view of SEM image (Figure 2b), the PTCDA particles with rod-like structure are scattered into the 3D porous structure of PGC40. It is obvious that a homogeneous nanocomposite could not be obtained because of the low solubility of PTCDA. Fortunately, the PTCDA particles with rod-like structure are confined in the interconnected 3D porous network, which could enhance their conductivity and overcome the solubility in electrolyte compared with the pristine PTCDA (inset in Figure 2b). Furthermore, the morphology features of PGCs with different proportions of PTCDA (PGC20 and PGC60) are also investigated, which exhibit the similar interconnected 3D porous network with that of PGC40 (Figure S2). In order to further investigate the morphology features of PGC40, TEM images are applied. The low magnified TEM image confirms that the rod-like PTCDA particles were distributed in graphene network (Figure 2c). The high magnified TEM image reveals the rod-like 6


Page 6 of 28

Page 7 of 28 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


PTCDA particles are wrapped by graphene (Figure 2d). The FTIR spectroscopy is used to examine the chemical structure of the PGCs and the pristine PTCDA (Figure 3a). For the pristine PTCDA, there are four characteristic peaks at 1774, 1756, 1743 and 1730 cm-1 that are related with the stretching vibration of C=O, two characteristic peaks at 1150 and 1122 cm-1 corresponding to the stretching modes of C-O and three characteristic peaks at 1596, 1506 and 1405 cm-1 that are related with symmetric stretching vibration from benzene ring skeleton.26,38 One can find the similar characteristic peaks for PGC40, suggesting that the PTCDA has been successfully incorporated into the 3D hybrid architecture. By contrast, the PGC60 shows the more obvious characteristic peaks, while the PGC20 shows the relatively weaker characteristic peaks (Figure S3a), which could be attributed to the different contents of the PTCDA in this composite. In order to further investigate the phase composition of the samples, XRD test is also conducted and the corresponding patterns are shown in Figure 3b. The pristine PTCDA displays three sharp peaks at 12.31o, 24.65o and 27.46o and a small peak at 17.16o, respectively, suggesting the PTCDA with a β-crystalline form.22,39-40 Interestingly, these similar peaks could be also detected in the PGC20 and PGC40 (Figure S3b), also suggesting the formation of the PTCDA and graphene composite. Raman spectra are also measured to study the formation of various samples (Figure 3c). It is obvious that the two strong peaks at 1344 and 1592 cm-1 could be observed in graphene, which are related with the disordered (D) band and graphitic (G) band, respectively.41 These peaks at 1051, 1310, 1381, 1576 and 1593 cm-1 of the pristine PTCDA may be due to the PTCDA with a certain crystal structure. Importantly, the peaks of PTCDA are maintained in PGC40, while the D and G band of graphene show blue-shift to 1335 and 1583 cm-1 and the peaks of PTCDA blue-shift to 1042, 1293, 1372, 1566 and 1583 cm-1, which may 7



result from the strong π-π interactions between graphene and PTCDA. In addition, the peaks at 1292, 1373 and 1565 cm-1 are enhanced obviously, which could be attributed to presence of graphene in the composites. Nitrogen adsorption-desorption measurement with Brunauer-Emmett-Teller (BET) analyzer is used to study the specific surface area and the pore characteristics of PGCs. As shown in the Figure 3d, the isotherm can be classified as a type Ⅲ curve with adsorption excess at the relative pressure of 0.8-1.0, which indicates the existence of the typical mesoporous characteristics in PGC40. The BET specific surface area (SSA) of PGC40 can be measured to be 59.3 m2 g-1 and the pore size distribution mainly ranges from 4 to 20 nm. In addition, the PGC20 shows the BET SSA of 80 m2 g-1, while the PGC60 shows the BET SSA of 60 m2 g-1. It is obvious that the increase of PTCDA in composite has a slight effect on the BET SSA (Figure S4). Interestingly, the higher SSA and mesoporous structure will be helpful to facilitate the permeation of electrolyte and shorten Li+ ions diffusion length, ensuring a relatively good electrochemical performance. The Li+ storage properties of PGCs as cathode materials in LIBs are evaluated in half cell using Li foil as anode. Typically, PGC40 undergoes cyclic voltammetry (CV) experiment scanned from 1.5 to 4.5 V at a scan rate of 0.1 mV s-1 (Figure 4a). There are two reduction peaks at 2.3 and 2.2 V during the cathodic scan and two oxidation peaks located 2.6 V and 2.7 V during anodic scan. The two oxidation peaks completely resulted from the PTCDA (Figure S5) demonstrate a two-step reaction with lithium ions for PGC40.22,24,38 In the subsequent scans, the shape and areas of the CV peaks remain almost unchanged, implying excellent electrochemical reversibility and cycling stability. Herein, the broadened and split peaks could result from the fast transformation between the radical anion and dianion, and the affect of the 8


Page 8 of 28

Page 9 of 28 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


electrolyte.23,38 The electrochemical mechanism of PGC40 originates from that of the PTCDA. Figure S6 shows the redox mechanism of PTCDA with two-step process, accompanied by four electron-transfers for each unit of PTCDA with theoretical capacity of 273 mAh g-1.22,24 The opposite positions of carbonyl groups can receive two electrons and insert two Li+/Na+ ions to form lithium/sodium enolate during the first-step discharge process.38 And the other two carbonyl groups can combine with two Li+/Na+ ions to form lithium/sodium enolate during the second-step discharge process.38 Then a conjugated structure with carbonyl groups could be formed, which could promote the redox enolation reaction.22,24,38 The Li+/Na+ ions are deinserted and the carbonyl groups are rebuilt in the reverse oxidation process. Early investigations have confirmed that a deep-discharge potential below 1.0 V could promote the additional two-step process,22, 24 which is more suitable as anode. Figure 4b shows the galvanostatic charge/discharge curves of PGC40 from various cycles at 50 mA g-1. Two plateaus around 2.3 V in the discharge process are observed, suggesting that the PTCDA can receive two electrons and insert two Li+ ions to form lithium enolate. In addition, there are two plateaus at 2.6 V in the charge process, indicating that the carbonyl groups are rebuilt and Li+ ions are deinserted, similar with the CV curves, which could be clearly verified by the local enlarged results (Figure S7). Furthermore, one can find that the initial discharge/charge capacities are 152 and 202 mAh g-1, respectively, higher than the specific capacity of PTCDA, corresponding to the synergistic effect of PTCDA and graphene.42 In addition, unique 3D porous structure may provide more attachment points for Li+, increasing the capacity of the hybrid materials. Figure 4c shows the cycling stability of the different samples at 50 mA g-1. It is shown that the pristine PTCDA exhibits poor Li storage behavior including low capacity and fast capacity fading (Figure S8). The initial capacity of 130 mAh g-1 9



quickly reduces to 60 mAh g-1 after 60 cycles with a much lower capacity retention of only 46%. To clearly understand the effect of different ratios between PTCDA and graphene, concentration-dependent experiments by changing the content of PTCDA in mixed solution are carried out. The initial capacities for PGC20 and PGC60 are 164.6, and 167.4 mAh g-1, respectively (Figure S9). The capacities of PGC20 and PGC60 decrease to 164 and 115.2 mAh g-1 after 100 cycles, respectively. By contrast, PGC40 displays high initial capacity of 202.2 mAh g-1 and the reversible capacity could retain 211 mAh g-1 after 200 cycles with the high Coulombic efficiency above 98%. It is obvious that the low content compromises the capacity and the high content results in the poor cycling stability. In addition, the enhanced conductivity is also beneficial to increase the capacity. Therefore, moderate loading content of PTCDA in composite aerogel is necessary.28 To investigate the reaction kinetics of various samples, electrochemical impedance spectroscopy (EIS) is investigated. As shown in Figure 4d, all the samples show the similar Nyquist plots. The same equivalent circuit mode is used to fit all the EIS plots (Figure 4e), in which R1 is related to the Ohmic resistance and solution resistance, R2 represents the charge transfer resistance between the electrolyte interface and electrode, CPE1 is the constant phase-angle element that is related to the double layer capacitance and W1 is the Warburg impedance that is related with the ion diffusion impedance in the active materials.28,43 For better comparison, the corresponding values from EIS plots are summarized (Figure 4f). It can be observed that the PGCs show substantially lower R2 values compared with PTCDA, that is, the semicircle with a smaller diameter of the PGCs compared with that of PTCDA. In addition, the PGCs show lower Warburg impedance, as reflected by the short inclined lines with larger phase angles at low frequency region. These results demonstrates that the incorporation of graphene endows the PGCs with the 10


Page 10 of 28

Page 11 of 28 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


enhanced kinetics of Li+ ions migration through the SEI film or within the electrodes and faster charge transfer reaction.28 It is obvious that an interconnected 3D porous graphene network wrapped PTCDA particles can enhance the electric conductivity and benefit the diffusion Li+ ion. Therefore, the Li storage capacity and cyclic stability of PGC are extremely improved after immobilization of PTCDA in the 3D porous graphene. In addition to PTCDA, our strategy could be further extended to construct other organic aromatic carbonyl compound/graphene aerogels, such as pyromellitic dianhydride (PMDA)/graphene aerogel and naphthalenetetracarboxylic dianhydride (NTCDA)/graphene aerogel. The corresponding FT-IR spectra (Figure S10) confirm the formation of the composite aerogel. Interestingly, these composite aerogels also show good electrochemical properties, including the high reversible capacity of 107 mAh g-1 after 100 cycles at 50 mA g-1 for PMDA/graphene aerogel and the reversible capacity of 108 mAh g-1 after 100 cycles at 50 mA g-1 for NTCDA/graphene aerogel (Figure S11). To further demonstrate the superiority of PGC40, the cycling stability at higher current density is applied (Figure 5a). PGC40 shows the reversible capacity of 124.5 mAh g-1 after 500 cycles at 100 mA g-1, corresponding to a much higher capacity retention ratio of 92%. In order to disclose the improved cycling performance, SEM images are used to show the morphology of PGC40 after cycling (Figure S12). It can be seen that the cycled PGC40 electrode shows the integrated surface structure without microcracks on the surface and PGC40 still maintains the 2D graphene nanosheets, suggesting that the introduced graphene can preserve the structural integrity of the electrode, which can prohibit the dissolution of the organic aromatic carbonyl compounds and result in the strong contacts between organic materials and graphene as well as the Al foil. Unexpectedly, even at a very high current density of 1000 mA 11



g-1, PGC40 can display the reversible capacity of 78 mAh g-1 after 500 cycles with a capacity retention ratio of 66%. This organic aromatic carbonyl compound/graphene aerogel shows the enhanced performance in both capacity and cycle stability, which are definitely superior to previously reported organic cathodes and organic/carbon hybrid composite cathode (Table S1). To further examine the rate capability of PGC40, the electrodes are tested under programmed current densities from 50 to 2000 mA g-1. Figure 5b shows the initial charge/discharge curves of PGC40 at various current densities. At lower current densities, both the charge and discharge curves show two voltage plateaus, while the polarization becomes serious at higher current densities. Figure 5c delivers the reversible capacities of 188, 170, 133, 104 and 86 mAh g-1 at the current densities of 50, 100, 200, 500 and 1000 mA g-1, respectively. Interestingly, PGC40 can also deliver the capacity of 64 mAh g-1 at higher current density of 2000 mA g-1. More strikingly, the capacity of PGC40 is capable of gradual recovery to 191 mAh g-1 with the current density switches back to 50 mA g-1 after being tested at varied current densities. As a proof of concept, PGC40 is assembled into a full cell, in which the graphite is used as the anode materials (details see experimental section) and its electrochemical performance is investigated. Figure 6a displays the charge and discharge profiles at 50 mA g-1, which present a high average discharge voltage of >2.2 V and high initial discharge/charge capacities of 173 mAh g-1 and 152 mAh h-1, respectively. In addition, the reversible capacity could be retained at 53 mAh g-1 after 120 cycles (Figure 6b). As a concept of application, the full cell can power an LED light (inset in Figure 6b). Subsequently, the Na+ storage properties of PGC40 as cathode materials in SIBs is further evaluated, in which PGC40 is employed as cathode materials and sodium foil as anode. Considering that SIBs show lower electrochemical potential (Na 2.71 vs. Li 12


Page 12 of 28

Page 13 of 28 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


3.04 with respect to SHE), PGC40 is tested with voltage of 1.5-3.5 V. Firstly, the cyclic voltammetry (CV) experiment is investigated (Figure 7a). In the first cycle, only a reduction peak appears at 2.0 V and two oxidation peaks located 2.1 V and 2.5V. However, in the following cycles, two reduction peaks at 2.5 V and 2.1 V reflect the insertion of Na+ and two oxidation peaks located 2.1 V and 2.5 V during anodic scan correspond to the de-insertion of Na+.24,38 Figure 7b displays the typical galvanostatic charge/discharge curves of PGC40 at 25 mA g-1. It is observed that there is a plateau around 2.0 V in the first discharge process and two plateaus located at 2.5 V and 2.1 V in the following discharge process, suggesting that the PTCDA receives two electrons and inserts two Na+ ions to form sodium enolate. In addition, in the charge process, there are two plateaus at 2.1 V and 2.5 V, indicating the carbonyl groups are rebuilt and Na+ are deinserted, agreeing with the CV curves. In addition, PGC40 shows the initial discharge/charge capacities of 81 and 97 mAh g-1, respectively. In subsequent cycles, the discharge capacity can be achieved ~93 mAh g-1. Figure 7c depicts that PGC40 shows a reversible capacity of 60.5 mAh g-1 after 600 cycles with a capacity retention ratio of 75% and also maintains high coulombic efficiency of almost 100%. Even higher current densities of 50 and 100 mA g-1 are applied, PGC40 shows the reversible capacity of 56.3 and 51 mAh g-1 after 1000 cycles with capacity retention ratio of 66.9 and 66.4% (Figure S13). Furthermore, the rate performance of PGC40 is further investigated at various current densities (Figure 7d). It can observe that the reversible capacities of PGC40 are 96, 94, 93, 86, 67, 43 and 32 mAh g-1 at current densities of 25, 50, 100, 200, 500, 1000 and 2000 mA g-1, respectively. Moreover, a capacity of 93 mAh g-1 is obtained when the current density is reduced to 25 mA g-1. Based on these results above, it is obvious that the PGCs as cathode materials for LIBs/SIBs shows the good electrochemical properties, which originates from the 13



successful integration of PTCDA and graphene. On one hand, aromatic carbonyl compound are confined in the 3D hybrid architecture along with the π-π interactions between the large aromatic core and graphene effectively suppress the dissolution of active material, thus guarantee the long cycling performance. On the other hand, 3D porous graphene with large specific surface area not only significantly enhances the conductivity, but also affords good Li+/Na+ ions accessibility to the organic electroactive material and shortens the Li+/Na+ ions diffusion length, thus guarantee good rate capability. Conclusions In summary, we have successfully prepared ultralight materials based on aromatic carbonyl compound/graphene aerogel. With this design, the PTCDA, as a representative example of aromatic carbonyl compounds, is nano-confined into the 3D porous graphene, which not only significantly enhances the accessibility of electrochemically active PTCDA molecules to Li+ ions, but also benefits effectively electron transfer and shortens the diffusion length of Li+ ions. Therefore, the PGCs as cathode materials for LIBs/SIBs exhibit the superior electrochemical properties with high storage capacity Li+/Na+ ions, long cycling performance, and advanced rate capability. Given the simplicity of the synthesis strategy and outstanding electrochemical performance of the resultant electrode materials, we believe that this study could pave a way for effective design and preparation of high-performance organic materials for energy storage applications. ASSOCIATED CONTENT Supporting Information Additional results for Experimental Section, SEM images, XRD patterns, FTIR spectra, nitrogen adsorption-desorption isotherms and corresponding pore-size 14


Page 14 of 28

Page 15 of 28 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


distributions, XPS spectra, CV curves, discharge/charge voltage profiles and cycling performance of various samples. AUTHOR INFORMATION Corresponding Author *E-mail: [email protected] (H.G. Wang) Notes The authors declare no competing financial interest. ACKNOWLEDGMENT This work was financially supported by the National Natural Science Foundation of China (Grant No. 21404014), the Science & Technology Department of Jilin Province (20170101177JC) and the Education Department of Jilin Province (No. 2016364). REFERENCES (1) Armand, M.; Tarascon, J. M. Building Better Batteries. Nature 2008, 451, 652-657. (2) Song, Z.; Zhou, H. Towards Sustainable and Versatile Energy Storage Devices: an Overview of Organic Electrode Materials. Energy Environ. Sci. 2013, 6, 2280-2301. (3) Tarascon, J. M.; Armand, M. Issues and Challenges Facing Rechargeable Lithium Batteries. Nature 2001, 414, 359-367. (4) Winter, M.; Brodd, R. J. What are Batteries, Fuel Cells, and Supercapacitors? Chem. Rev. 2004, 104, 4245-4249. (5) Poizot, P.; Laruelle, S.; Grugeon, S.; Dupont, L.; Tarascon, J. M. Nano-Sized Transition-Metal Oxides as Negative-Electrode Materials for Lithium-Ion Batteries. Nature 2000, 407, 496-499. (6) Simon, P.; Gogotsi, Y. Materials for Electrochemical Capacitors. Nat. Mater. 2008, 7, 845-854. 15



(7) Qiu, B. C.; Xing, M. Y.; Zhang, J. L. Mesoporous TiO2 Nanocrystals Grown in Situ on Graphene Aerogels for High Photocatalysis and Lithium-Ion Batteries. J. Am. Chem. Soc. 2014, 136, 5852-5855. (8) Qiu, B. C.; Li, Q. Y.; Shen, B.; Xing, M. Y.; Zhang, J. L. Stöber-like method to Synthesize Ultradispersed Fe3O4 Nanoparticles on Graphene with Excellent Photo-Fenton Reaction and High-Performance Lithium Storage. Appl. Catal. B: Environ. 2016, 183, 216-223. (9) Mizushima, K.; Jones, P. C.; Wiseman, P. J.; Goodenough, J. B. LixCoO2 (0 < x ≤1): A New Cathode Material for Batteries of High Energy Density. Mater. Res. Bull. 1980, 15, 783-789. (10) Xu, B.; Qian, D.; Wang, Z.; Meng, Y. S. Recent Progress in Cathode Materials Research for Advanced Lithium Ion Batteries. Mater. Sci. Eng. R 2012, 73, 51-65. (11) Tarascon, J. M.; Guyomard, D. The Li1+xMn2O4/C Rocking Chair System: A Review. Electrochim. Acta 1993, 38, 1221-1231. (12) Whittingham, M. S. Lithium Batteries and Cathode Materials. Chem. Rev. 2004, 104, 4271-4301. (13) Xu, G. L.; Wang, Q.; Fang, J. C.; Xu, Y. F.; Li, J. T.; Huang, L.; Sun, S. G. Tuning the Structure and Property of Nanostructured Cathode Materials of Lithium Ion and Lithium Sulfur Batteries. J. Mater. Chem. A 2014, 2, 19941-19962. (14) Sun, Y. K.; Myung, S. H.; Kim, M. H.; Prakash, J.; Amine, K. Synthesis and Characterization of Li[(Ni0.8Co0.1Mn0.1)0.8(Ni0.5Mn0.5)0.2]O2 with the Microscale Core-Shell Structure as the Positive Electrode Material for Lithium Batteries. J. Am. Chem. Soc. 2005, 127, 13411-13418. (15) Cho, J.; Kim, Y. W.; Kim, B.; Lee, J. G.; Park, B. A Breakthrough in the Safety of Lithium Secondary Batteries by Coating the Cathode Material with AlPO4 16


Page 16 of 28

Page 17 of 28 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


Nanoparticles. Angew. Chem. Int. Ed. 2003, 42, 1618-1621. (16) Liang, Y. L.; Tao, Z. L.; Chen, J. Organic Electrode Materials for Rechargeable Lithium Batteries. Adv. Energy Mater. 2012, 2, 742-769. (17) Zhao, Q.; Lu, Y.; Chen, J. Advanced Organic Electrode Materials for Rechargeable Sodium-Ion Batteries. Adv. Energy Mater. 2017, 7, 1601792. (18) Häupler, B.; Wild, A.; Schubert, U. S. Carbonyls: Powerful Organic Materials for Secondary Batteries. Adv. Energy Mater. 2015, 5, 1402034. (19) Liang, Y.; Zhang, P.; Chen, J. Function-Oriented Design of Conjugated Carbonyl Compound Electrodes for High Energy Lithium Batteries. Chem. Sci. 2013, 4, 1330-1337. (20) Wu, Y. W.; Zeng, R. H.; Nan, J. M.; Shu, D.; Qiu, Y. C.; Chou, S. L. Quinone Electrode Materials for Rechargeable Lithium/Sodium Ion Batteries. Adv. Energy Mater. 2017, 7, 1700278. (21) Chen, H.; Armand, M.; Demailly, G.; Dolhem, F.; Poizot, P.; Tarascon, J. M. From Biomass to a Renewable LixC6O6 Organic Electrode for Sustainable Li-Ion Batteries. Chemsuschem 2008, 1, 348-355. (22) Han, X. Y.; Chang, C. X.; Yuan, L. J.; Sun, T. L.; Sun, J. T. Aromatic Carbonyl Derivative Polymers as High-Performance Li-Ion Storage Materials. Adv. Mater. 2010, 19, 1616-1621. (23) Song, Z. P.; Zhan, H.; Zhou, Y. H. Polyimides: Promising Energy-Storage Materials. Angew. Chem. Int. Ed. 2010, 49, 8444-8448. (24) Luo, W.; Allen, M.; Raju, V.; Ji, X. L. An Organic Pigment as a High-Performance Cathode for Sodium-Ion Batteries. Adv. Energy Mater. 2014, 4, 1400554. (25) Chen, D. Y.; Avestro, A. J.; Chen, Z. H.; Sun, J. L.; Wang, S. J.; Xiao, M.; Erno, 17



Page 18 of 28

Z.; Algaradah, M. M.; Nassar, M. S.; Amine, K.; Meng, Y. Z.; Stoddart, J. F. A Rigid Naphthalenediimide Triangle for Organic Rechargeable Lithium-Ion Batteries. Adv. Mater. 2015, 27, 2907-2912. (26) Banda, H.; Damien, D.; Nagarajan, K.; Hariharan, M.; Shaijumon, M. M. A Polyimide based all-Organic Sodium Ion Battery. J. Mater. Chem. A 2015, 3, 10453-10458. (27) Meng, Y.; Wu, H.; Zhang, Y.; Wei, Z. A. Flexible Electrode based on a Three-Dimensional Graphene Network-Supported Polyimide for Lithium-Ion Batteries. J. Mater. Chem. A 2014, 2, 10842-10846. (28) Ai, W.; Zhou, W.; Du, Z.; Sun, C.; Yang, J.; Chen, Y.; Sun, Z.; Feng, S.; Zhao, J.; Dong, X.; Huang, W.; Yu, T. Toward High Energy Organic Cathodes for Li-Ion Batteries: A Case Study of Vat Dye/Graphene Composites. Adv. Funct. Mater. 2017, 27, 1603603. (29) Yang, G.; Bu, F.; Huang, Y., Zhang, Y.; Shakir, I., Xu, Y. In-Situ Growth and Wrapping of Aminoanthraquinone Nanowires within 3D Graphene Framework as High-Performance

Foldable

Organic

Cathode

for

Lithium

Ion

Batteries.

Chemsuschem 2017, 10, 3419-3426. (30) Lyu, H.; Li, P.; Liu, J.; Mahurin, S.; Chen, J.; Hensley, D. K.; Veith, G. M.; Guo, Z.; Dai, S.; Sun, X. G. Aromatic Polyimide/Graphene Composite Organic Cathodes for

Fast

and

Sustainable

Lithium-Ion

Batteries.

ChemSusChem

2018,

doi.org/10.1002/cssc.201702001. (31) Huang, Y.; Li, K.; Liu, J.; Zhong, X.; Duan, X.; Shakir, I.; Xu Y. Three-Dimensional

Graphene/Polyimide

Composite-Derived

Flexible

High-Performance Organic Cathode for Rechargeable Lithium and Sodium Batteries. J. Mater. Chem. A 2017, 5, 2710-2716. 18


Page 19 of 28 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


(32) Cui, D.; Tian, D.; Chen, S.; Yuan, L. Graphene Wrapped 3, 4, 9, 10Perylenetetracarboxylic Dianhydride as High-Performance Organic Cathode for Lithium Ion Batteries. J. Mater. Chem. A 2016, 4, 9177-9183. (33) Wu, H.; Wang, K.; Meng, Y.; Lu, K.; Wei, Z. An Organic Cathode Material Based on a Polyimide/CNT Nanocomposite for Lithium Ion Batteries. J. Mater. Chem. A 2013, 1, 6366-6372 (34) Xiong, D.; Li, X.; Shan, H.; Yan, B.; Dong, L.; Cao, Y.; Li, D. Controllable Oxygenic Functional Groups of Metal-free Cathodes for High Performance Lithium Ion Batteries. J. Mater. Chem. A 2015, 3, 11376-11386. (35) Lu, Y.; Zhang, N.; Jiang, S.; Zhang Y.; Zhou, M.; Tao, Z.; Archer L. A.; Chen, J. High-capacity and Ultrafast Na-ion Storage of Self-supported 3D Porous Antimony Persulfide@graphene Foam Architecture. Nano Lett 2017, 17, 3668-3674. (36) Zhang, Y.; Huang, Y.; Yang, G.; Bu, F.; Li, K.; Shakir, I.; Xu, Y. Dispersion-Assembly Approach to Synthesize Three-Dimensional Graphene/Polymer Composite Aerogel as a Powerful Organic Cathode for Rechargeable Li and Na Batteries. ACS Appl. Mater. Inter. 2017, 9, 15549-15556. (37) Hummers, W. S.; Offeman, R. E. Preparation of Graphitic Oxide. J. Am. Chem. Soc. 1958, 80, 1339. (38) Wang, H. G.; Yuan, S.; Ma, D. L.; Huang, X. L.; Meng, F. L.; Zhang, X. B. Tailored Aromatic Carbonyl Derivative Polyimides for High-Power and Long-Cycle Sodium-Organic Batteries. Adv. Energy Mater. 2014, 4, 1301651. (39) Forrest, S. R. Ultrathin Organic Films Grown by Organic Molecular Beam Deposition and Related Techniques. Chem. Rev. 1997, 97, 1793-1896.

19



Page 20 of 28

(40) Ogawa, T.; Kuwamoto, K.; Isoda, S.; Kobayashi, T.; Karl, N. 3, 4, 9, 10-Perylenetetracarboxylicdianhydride (PTCDA) by Electron Crystallography. Acta Crystallogr. Sect. B 1999, 55, 123-130. (41) Jiang, C.; Yuan, C.; Li, P.; Wang, H. G.; Li, Y. H.; Duan, Q. Nitrogen-Doped Porous Graphene with Surface Decorated MnO2 Nanowires as a High-Performance Anode Material for Lithium-Ion Batteries. J. Mater. Chem. A 2016, 4, 7251-7256. (42)

Wang,

H.;

Hu,

P.;

Yang,

J.;

Gong,

G.;

Guo,

L.;

Chen,

X.

Renewable-Juglone-based High-Performance Sodium-Ion Batteries. Adv. Mater. 2015, 27, 2348-2354. (43) Zhang, S. S.; Xu, K.; Jow, T. R. Electrochemical Impedance Study on the Low Temperature of Li-Ion Batteries. Electrochim. Acta 2004, 49, 1057-1061.

20


Page 21 of 28 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


Figure 1. Schematic illustration of the fabrication process for the PGC.

21



Figure 2. (a) SEM image of PGC40 (top view) and digital photographs of the PGC hydrogel and PGC aerogel (inset), (b) SEM image of PGC40 (side view) and digital photographs of PTCDA and PGC40 in the electrolyte (inset), and (c and d) different-magnified TEM images of PGC40.

22


Page 22 of 28

Page 23 of 28 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


Figure 3. (a) FTIR spectra and (b) XRD patterns of PTCDA and PGC40, (c) Raman spectra of GO, PTCDA and PGC40, (d) nitrogen adsorption-desorption isotherm of PGC40 and corresponding pore-size distribution (inset).

23



Figure 4. Electrochemical characterization of PGC40 as cathode materials for LIBs: (a) CV curves of the PGC40 at a scan rate of 0.1 mV s-1, (b) galvanostatic charge-discharge curves of PGC40 at 50 mA g-1, (c) cycling performance of different samples at 50 mA g-1, (d) electrochemical impedance spectra of different samples at a range of 100 kHz to 10 mHz, (e) the equivalent circuit model used for fitting the EIS and the coresponding fitting results for different electrodes (f). 24


Page 24 of 28

Page 25 of 28 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


Figure 5. Electrochemical characterization of PGC40 as cathode materials for LIBs: (a) cycling performance of PGC40 at 100 mA g-1 and 1000 mA g-1, (b) galvanostatic charge-discharge curves and (c) rate performance at different current densities.

25



Figure 6. Electrochemical characterization of PGC40 as cathode materials for a full cell: (a) galvanostatic charge-discharge curves, (b) cycling performance at 50 mA g-1 and photograph of a light-emitting-diode powered by the full cell (inset).

26


Page 26 of 28

Page 27 of 28 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


Figure 7. Electrochemical characterization of PGC40 as cathode materials for SIB: (a) CV curves at a scan rate of 0.1 mV s-1 in the range of 1.5-3.5 V, (b) galvanostatic charge-discharge curves at 25 mA g-1, (c) cycling performance at 25 mA g-1, (d) rate performance at different current densities.

27



Page 28 of 28

Table of Contents Graphic

An effective strategy to prepare nanoengineered ultralight materials based on organic electroactive

material/graphene

aerogel,

which

shows

performance as cathode materials for Li- and Na-ion batteries.

28


high

electrochemical

Nanoengineered Ultralight Organic Cathode Based on Aromatic

Recommend Documents