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1.
Rufan Chen Ji‐Long Shi Yuan Ma Guiqing Lin Xianjun Lang Cheng Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(19):6496-6500
The construction of stable covalent organic frameworks (COFs) for various applications is highly desirable. Herein, we report the synthesis of a novel two‐dimensional (2D) porphyrin‐based sp2 carbon‐conjugated COF (Por‐sp2c‐COF), which adopts an eclipsed AA stacking structure with a Brunauer—Emmett—Teller surface area of 689 m2 g?1. Owing to the C=C linkages, Por‐sp2c‐COF shows a high chemical stability under various conditions, even under harsh conditions such as 9 m HCl and 9 m NaOH solutions. Interestingly, Por‐sp2c‐COF can be used as a metal‐free heterogeneous photocatalyst for the visible‐light‐induced aerobic oxidation of amines to imines. More importantly, in comparison to imine‐linked Por‐COF, the inherent structure of Por‐sp2c‐COF equips it with several advantages as a photocatalyst, including reusability and high photocatalytic performance. This clearly demonstrates that sp2 carbon‐linked 2D COFs can provide an interesting platform for heterogeneous photocatalysis. 相似文献
2.
Qiang Jiang Peixun Xiong Jingjuan Liu Zhen Xie Qinchao Wang Xiao‐Qing Yang Enyuan Hu Yu Cao Jie Sun Yunhua Xu Long Chen 《Angewandte Chemie (International ed. in English)》2020,59(13):5273-5277
Metal–organic framework cathodes usually exhibit low capacity and poor electrochemical performance for Li‐ion storage owing to intrinsic low conductivity and inferior redox activity. Now a redox‐active 2D copper–benzoquinoid (Cu‐THQ) MOF has been synthesized by a simple solvothermal method. The abundant porosity and intrinsic redox character endow the 2D Cu‐THQ MOF with promising electrochemical activity. Superior performance is achieved as a Li‐ion battery cathode with a high reversible capacity (387 mA h g?1), large specific energy density (775 Wh kg?1), and good cycling stability. The reaction mechanism is unveiled by comprehensive spectroscopic techniques: a three‐electron redox reaction per coordination unit and one‐electron redox reaction per copper ion mechanism is demonstrated. This elucidatory understanding sheds new light on future rational design of high‐performance MOF‐based cathode materials for efficient energy storage and conversion. 相似文献
3.
Songwei Gao Nü Wang Shuai Li Dianming Li Zhimin Cui Guichu Yue Jingchong Liu Xiaoxian Zhao Lei Jiang Yong Zhao 《Angewandte Chemie (International ed. in English)》2020,59(6):2465-2472
Multi‐wall Sn/SnO2@carbon hollow nanofibers evolved from SnO2 nanofibers are designed and programable synthesized by electrospinning, polypyrrole coating, and annealing reduction. The synthesized hollow nanofibers have a special wire‐in‐double‐wall‐tube structure with larger specific surface area and abundant inner spaces, which can provide effective contacting area of electrolyte with electrode materials and more active sites for redox reaction. It shows excellent cycling stability by virtue of effectively alleviating pulverization of tin‐based electrode materials caused by volume expansion. Even after 2000 cycles, the wire‐in‐double‐wall‐tube Sn/SnO2@carbon nanofibers exhibit a high specific capacity of 986.3 mAh g?1 (1 A g?1) and still maintains 508.2 mAh g?1 at high current density of 5 A g?1. This outstanding electrochemical performance suggests the multi‐wall Sn/SnO2@ carbon hollow nanofibers are great promising for high performance energy storage systems. 相似文献
4.
Ascorbic Acid‐Assisted Synthesis of Mesoporous Sodium Vanadium Phosphate Nanoparticles with Highly sp2‐Coordinated Carbon Coatings as Efficient Cathode Materials for Rechargeable Sodium‐Ion Batteries
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Dr. Tai‐Feng Hung Wei‐Jen Cheng Dr. Wen‐Sheng Chang Dr. Chang‐Chung Yang Dr. Chin‐Chang Shen Dr. Yu‐Lin Kuo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10620-10626
Herein, mesoporous sodium vanadium phosphate nanoparticles with highly sp2‐coordinated carbon coatings (meso‐Na3V2(PO4)3/C) were successfully synthesized as efficient cathode material for rechargeable sodium‐ion batteries by using ascorbic acid as both the reductant and carbon source, followed by calcination at 750 °C in an argon atmosphere. Their crystalline structure, morphology, surface area, chemical composition, carbon nature and amount were systematically explored. Following electrochemical measurements, the resultant meso‐Na3V2(PO4)3/C not only delivered good reversible capacity (98 mAh g?1 at 0.1 A g?1) and superior rate capability (63 mAh g?1 at 1 A g?1) but also exhibited comparable cycling performance (capacity retention: ≈74 % at 450 cycles at 0.4 A g?1). Moreover, the symmetrical sodium‐ion full cell with excellent reversibility and cycling stability was also achieved (capacity retention: 92.2 % at 0.1 A g?1 with 99.5 % coulombic efficiency after 100 cycles). These attributes are ascribed to the distinctive mesostructure for facile sodium‐ion insertion/extraction and their continuous sp2‐coordinated carbon coatings, which facilitate electronic conduction. 相似文献
5.
A New Anode for Lithium‐Ion Batteries Based on Single‐Walled Carbon Nanotubes and Graphene: Improved Performance through a Binary Network Design
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Carbon nanomaterials, especially graphene and carbon nanotubes, are considered to be favorable alternatives to graphite‐based anodes in lithium‐ion batteries, owing to their high specific surface area, electrical conductivity, and excellent mechanical flexibility. However, the limited number of storage sites for lithium ions within the sp2‐carbon hexahedrons leads to the low storage capacity. Thus, rational structure design is essential for the preparation of high‐performance carbon‐based anode materials. Herein, we employed flexible single‐walled carbon nanotubes (SWCNTs) with ultrahigh electrical conductivity as a wrapper for 3D graphene foam (GF) by using a facile dip‐coating process to form a binary network structure. This structure, which offered high electrical conductivity, enlarged the electrode/electrolyte contact area, shortened the electron‐/ion‐transport pathways, and allowed for efficient utilization of the active material, which led to improved electrochemical performance. When used as an anode in lithium‐ion batteries, the SWCNT‐GF electrode delivered a specific capacity of 953 mA h g?1 at a current density of 0.1 A g?1 and a high reversible capacity of 606 mA h g?1 after 1000 cycles, with a capacity retention of 90 % over 1000 cycles at 1 A g?1 and 189 mA h g?1 after 2200 cycles at 5 A g?1. 相似文献
6.
An Azine‐Linked Covalent Organic Framework: Synthesis,Characterization and Efficient Gas Storage
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Zhongping Li Yongfeng Zhi Xiao Feng Xuesong Ding Yongcun Zou Prof. Xiaoming Liu Prof. Ying Mu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(34):12079-12084
A azine‐linked covalent organic framework, COF‐JLU2, was designed and synthesized by condensation of hydrazine hydrate and 1,3,5‐triformylphloroglucinol under solvothermal conditions for the first time. The new covalent organic framework material combines permanent micropores, high crystallinity, good thermal and chemical stability, and abundant heteroatom activated sites in the skeleton. COF‐JLU2 possesses a moderate BET surface area of over 410 m2 g?1 with a pore volume of 0.56 cm3 g?1. Specifically, COF‐JLU2 displays remarkable carbon dioxide uptake (up to 217 mg g?1) and methane uptake (38 mg g?1) at 273 K and 1 bar, as well as high CO2/N2 (77) selectivity. Furthermore, we further highlight that it exhibits a higher hydrogen storage capacity (16 mg g?1) than those of reported COFs at 77 K and 1 bar. 相似文献
7.
Polypyrrole Shell@3D‐Ni Metal Core Structured Electrodes for High‐Performance Supercapacitors
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Gao‐Feng Chen Yu‐Zhi Su Pan‐Yong Kuang Zhao‐Qing Liu Dao‐Yi Chen Xu Wu Nan Li Prof. Shi‐Zhang Qiao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(12):4614-4621
Three‐dimensional (3D) nanometal films serving as current collectors have attracted much interest recently owing to their promising application in high‐performance supercapacitors. In the process of the electrochemical reaction, the 3D structure can provide a short diffusion path for fast ion transport, and the highly conductive nanometal may serve as a backbone for facile electron transfer. In this work, a novel polypyrrole (PPy) shell@3D‐Ni‐core composite is developed to enhance the electrochemical performance of conventional PPy. With the introduction of a Ni metal core, the as‐prepared material exhibits a high specific capacitance (726 F g?1 at a charge/discharge rate of 1 A g?1), good rate capability (a decay of 33 % in Csp with charge/discharge rates increasing from 1 to 20 A g?1), and high cycle stability (only a small decrease of 4.2 % in Csp after 1000 cycles at a scan rate of 100 mV s?1). Furthermore, an aqueous symmetric supercapacitor device is fabricated by using the as‐prepared composite as electrodes; the device demonstrates a high energy density (≈21.2 Wh kg?1) and superior long‐term cycle ability (only 4.4 % and 18.6 % loss in Csp after 2000 and 5000 cycles, respectively). 相似文献
8.
Heteroatom‐Doped Porous Carbon Nanosheets: General Preparation and Enhanced Capacitive Properties
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Xiaodong Hao Jie Wang Bing Ding Laifa Shen Yunling Xu Ya Wang Zhi Chang Hui Dou Xiangjun Lu Prof. Xiaogang Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(46):16668-16674
High‐performance electrical double‐layer capacitors (EDLCs) require carbon electrode materials with high specific surface area, short ion‐diffusion pathways, and outstanding electrical conductivity. Herein, a general approach combing the molten‐salt method and chemical activation to prepare N‐doped carbon nanosheets with high surface area (654 m2 g?1) and adjustable porous structure is presented. Owing to their structural features, the N‐doped carbon nanosheets exhibited superior capacitive performance, demonstrated by a maximum capacitance of 243 F g?1 (area‐normalized capacitance up to 37 μF cm?2) at a current density of 0.5 A g?1 in aqueous electrolyte, high rate capability (179 F g?1 at 20 A g?1), and excellent cycle stability. This method provides a new route to prepare porous and heteroatom‐doped carbon nanosheets for high‐performance EDLCs, which could also be extended to other polymer precursors and even waste biomass. 相似文献
9.
Liwei Cheng Yanhong Liang Qiaonan Zhu Dandan Yu Mengxue Chen Junfei Liang Hua Wang 《化学:亚洲杂志》2020,15(8):1290-1295
Organic electrode materials hold great potential for fabricating sustainable energy storage systems, however, the development of organic redox‐active moieties for rechargeable aqueous zinc‐ion batteries is still at an early stage. Here, we report a bio‐inspired riboflavin‐based aqueous zinc‐ion battery utilizing an isoalloxazine ring as the redox center for the first time. This battery exhibits a high capacity of 145.5 mAh g?1 at 0.01 A g?1 and a long‐life stability of 3000 cycles at 5 A g?1. We demonstrate that isoalloxazine moieties are active centers for reversible zinc‐ion storage by using optical and photoelectron spectroscopies as well as theoretical calculations. Through molecule‐structure tailoring of riboflavin, the obtained alloxazine and lumazine molecules exhibit much higher theoretical capacities of 250.3 and 326.6 mAh g?1, respectively. Our work offers an effective redox‐active moiety for aqueous zinc batteries and will enrich the valuable material pool for electrode design. 相似文献
10.
A novel ferrocene‐containing porous organic polymer (FPOP) has been prepared by Sonogashira‐Hagihara coupling reaction of 1,1′‐dibromoferrocene and tetrakis(4‐ethynylphenyl)silane. Compared with other polymers, the resulting polymer possesses excellent thermal stability with the decomposition temperature of 415°C and high porosity with Brunauer–Emmett–Teller (BET) surface area of 542 m2 g?1 as measured by nitrogen adsorption‐desoprtion isotherm at 77 K. For applications, it shows moderate carbon dioxide uptakes of up to 1.42 mmol g?1 (6.26 wt%) at 273 K/1.0 bar and 0.82 mmol g?1 (3.62 wt%) at 298 K/1.0 bar, and hydrogen capacity of up to 0.45 mmol g?1 (0.91 wt%) at 77 K/1.0 bar, indicating that FPOP might be utilized as a promising candidate for storing carbon dioxide and hydrogen. Although FPOP possesses lower porosity than many porous polymers, the gas capacities are higher or comparable to them, thereby revealing that the incorporation of ferrocene units into the network is an effective strategy to enhance the affinity between the framework and gas. 相似文献
11.
Electric Double‐Layer Capacitors Based on Highly Graphitized Nanoporous Carbons Derived from ZIF‐67
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Nagy L. Torad Rahul R. Salunkhe Yunqi Li Hicham Hamoudi Masataka Imura Prof. Dr. Yoshio Sakka Prof. Dr. Chi‐Chang Hu Prof. Dr. Yusuke Yamauchi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(26):7895-7900
Nanoporous carbons (NPCs) have large specific surface areas, good electrical and thermal conductivity, and both chemical and mechanical stability, which facilitate their use in energy storage device applications. In the present study, highly graphitized NPCs are synthesized by one‐step direct carbonization of cobalt‐containing zeolitic imidazolate framework‐67 (ZIF‐67). After chemical etching, the deposited Co content can be completely removed to prepare pure NPCs with high specific surface area, large pore volume, and intrinsic electrical conductivity (high content of sp2‐bonded carbons). A detailed electrochemical study is performed using cyclic voltammetry and galvanostatic charge–discharge measurements. Our NPC is very promising for efficient electrodes for high‐performance supercapacitor applications. A maximum specific capacitance of 238 F g?1 is observed at a scan rate of 20 mV s?1. This value is very high compared to previous works on carbon‐based electric double layer capacitors. 相似文献
12.
Zhongping Li He Li Prof. Hong Xia Dr. Xuesong Ding Xiaolong Luo Prof. Xiaoming Liu Prof. Ying Mu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(48):17355-17362
A luminescent conjugated microporous polymer (BCMP‐3) has been synthesized in high yield by a carbon–carbon coupling reaction using triarylboron as a building unit. BCMP‐3 was fully characterized by using powder X‐ray diffraction analysis, Fourier transform infrared spectroscopy, 13C solid‐state NMR spectroscopy, field emission scanning electron microscopy, thermogravimetric analysis, and nitrogen and carbon dioxide adsorption. The new three‐dimensional conjugated framework possess a high Brunauer–Emmett–Teller (BET) specific surface area up to 950 m2 g?1 with a pore volume of 0.768 cm3 g?1, good stability, and abundant boron sites in the skeleton. Under excited‐light irradiation, BCMP‐3 exhibits strong fluorescent emission at 488 nm with a high absolute quantum yield of 18 % in the solid state. Polymer BCMP‐3 acts as a colorimetric and fluorescent chemosensor with high sensitivity and selectivity for F? over other common anions. In addition, the polymer also works as an adsorbent for F? removal and shows good adsorption capacities of up to 24 mg g?1 at equilibrium F? concentrations of 16 mg L?1 and a temperature of 298 K. The adsorption kinetics and isotherm were analyzed by fitting experimental data with pseudo‐second‐order kinetics and Langmuir equations. Furthermore, we highlight that BCMP‐3 is an adsorbent for fluoride removal that can be efficiently reused many times without loss of adsorption efficiency. 相似文献
13.
MnO2 Nanosheets Grown on Nitrogen‐Doped Hollow Carbon Shells as a High‐Performance Electrode for Asymmetric Supercapacitors
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Lei Li Rumin Li Shili Gai Prof. Shujiang Ding Fei He Prof. Milin Zhang Prof. Piaoping Yang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(19):7119-7126
A hierarchical hollow hybrid composite, namely, MnO2 nanosheets grown on nitrogen‐doped hollow carbon shells (NHCSs@MnO2), was synthesized by a facile in situ growth process followed by calcination. The composite has a high surface area (251 m2g?1) and mesopores (4.5 nm in diameter), which can efficiently facilitate transport during electrochemical cycling. Owing to the synergistic effect of NHCSs and MnO2, the composite shows a high specific capacitance of 306 F g?1, good rate capability, and an excellent cycling stability of 95.2 % after 5000 cycles at a high current density of 8 A g?1. More importantly, an asymmetric supercapacitor (ASC) assembled by using NHCSs@MnO2 and activated carbon as the positive and negative electrodes exhibits high specific capacitance (105.5 F g?1 at 0.5 A g?1 and 78.5 F g?1 at 10 A g?1) with excellent rate capability, achieves a maximum energy density of 43.9 Wh kg?1 at a power density of 408 W kg?1, and has high stability, whereby the ASC retains 81.4 % of its initial capacitance at a current density of 5 A g?1 after 4000 cycles. Therefore, the NHCSs@MnO2 electrode material is a promising candidate for future energy‐storage systems. 相似文献
14.
Yuxin Liu Prof. Ping Liu Prof. Dongqing Wu Yanshan Huang Yanping Tang Prof. Yuezeng Su Prof. Fan Zhang Prof. Xinliang Feng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(14):5617-5622
Heteroatom doping is an effective method to adjust the electrochemical behavior of carbonaceous materials. In this work, boron‐doped, carbon‐coated SnO2/graphene hybrids (BCTGs) were fabricated by hydrothermal carbonization of sucrose in the presence of SnO2/graphene nanosheets and phenylboronic acid or boric acid as dopant source and subsequent thermal treatment. Owing to their unique 2D core–shell architecture and B‐doped carbon shells, BCTGs have enhanced conductivity and extra active sites for lithium storage. With phenylboronic acid as B source, the resulting hybrid shows outstanding electrochemical performance as the anode in lithium‐ion batteries with a highly stable capacity of 1165 mA h g?1 at 0.1 A g?1 after 360 cycles and an excellent rate capability of 600 mA h g?1 at 3.2 A g?1, and thus outperforms most of the previously reported SnO2‐based anode materials. 相似文献
15.
Ji‐Long Shi Rufan Chen Huimin Hao Cheng Wang Xianjun Lang 《Angewandte Chemie (International ed. in English)》2020,59(23):9088-9093
2D covalent organic frameworks (COFs) are receiving ongoing attention in semiconductor photocatalysis. Herein, we present a photocatalytic selective chemical transformation by combining sp2 carbon‐conjugated porphyrin‐based covalent organic framework (Por‐sp2c‐COF) photocatalysis with TEMPO catalysis illuminated by 623 nm red light‐emitting diodes (LEDs). Highly selective conversion of amines into imines was swiftly afforded in minutes. Specifically, the π‐conjugation of porphyrin linker leads to extensive absorption of red light; the sp2 ?C=C? double bonds linkage ensures the stability of Por‐sp2c‐COF under high concentrations of amine. Most importantly, we found that crystalline framework of Por‐sp2c‐COF is pivotal for cooperative photocatalysis with (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl (TEMPO). This work foreshadows that the outstanding hallmarks of COFs, particularly crystallinity, could be exploited to address energy and environmental challenges by cooperative photocatalysis. 相似文献
16.
High‐Loading Nano‐SnO2 Encapsulated in situ in Three‐Dimensional Rigid Porous Carbon for Superior Lithium‐Ion Batteries
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Hairong Xue Dr. Jianqing Zhao Jing Tang Hao Gong Prof. Ping He Prof. Haoshen Zhou Prof. Yusuke Yamauchi Prof. Jianping He 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(14):4915-4923
Tin oxide nanoparticles (SnO2 NPs) have been encapsulated in situ in a three‐dimensional ordered space structure. Within this composite, ordered mesoporous carbon (OMC) acts as a carbon framework showing a desirable ordered mesoporous structure with an average pore size (≈6 nm) and a high surface area (470.3 m2 g?1), and the SnO2 NPs (≈10 nm) are highly loaded (up to 80 wt %) and homogeneously distributed within the OMC matrix. As an anode material for lithium‐ion batteries, a SnO2@OMC composite material can deliver an initial charge capacity of 943 mAh g?1 and retain 68.9 % of the initial capacity after 50 cycles at a current density of 50 mA g?1, even exhibit a capacity of 503 mA h g?1 after 100 cycles at 160 mA g?1. In situ encapsulation of the SnO2 NPs within an OMC framework contributes to a higher capacity and a better cycling stability and rate capability in comparison with bare OMC and OMC ex situ loaded with SnO2 particles (SnO2/OMC). The significantly improved electrochemical performance of the SnO2@OMC composite can be attributed to the multifunctional OMC matrix, which can facilitate electrolyte infiltration, accelerate charge transfer, and lithium‐ion diffusion, and act as a favorable buffer to release reaction strains for lithiation/delithiation of the SnO2 NPs. 相似文献
17.
A new fluorescent hybrid porous polymer (HPP) is synthesized by an anhydrous FeCl3‐mediated oxidative coupling reaction of octa[4‐(9‐carbazolyl)phenyl]silsesquioxane (OCPS). The polymer possesses a surface area of 1741 m2 g?1 and hierarchical bimodal micropores (1.41 and 1.69 nm) and mesopores (2.65 nm). The material serves as an excellent adsorbent for CO2 and dyes with high adsorption capacity for CO2 (8.53 wt %,1.94 mmol g?1), congo red (1715 mg g?1) and rhodamine B (1501 mg g?1). In addition, the presence of peripheral cabozolyl groups with extended π‐conjugation in the crosslinked framework imparts luminescent character to the polymer and offers the detection of nitroaromatic compounds. 相似文献
18.
Hengyang Cheng Jinku Meng Guan Wu Su Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(48):17626-17634
Advanced methods, allowing the controllable synthesis of ordered structural nanomaterials with favourable charges transfer and storage, are highly important to achieve ideal supercapacitors with high energy density. Herein, we report a microliter droplet‐based method to synthesize hierarchical‐structured metal–organic framework/graphene/carbon nanotubes hybrids. The confined ultra‐small‐volume reaction, give well‐defined hybrids with a large specific‐surface‐area (1206 m2 g?1), abundant ionic‐channels (narrow pore of 0.86 nm), and nitrogen active‐sites (10.63 %), resulting in high pore‐size utilization (97.9 %) and redox‐activity (32.3 %). We also propose a scalable microfluidic‐blow‐spinning method to consecutively generate nanofibre‐based flexible supercapacitor electrodes with striking flexibility and mechanical strength. The supercapacitors display large volumetric energy density (147.5 mWh cm?3), high specific capacitance (472 F cm?3) and stably deformable energy‐supply. 相似文献
19.
Dr. Md Mokhlesur Rahman Irin Sultana Dr. Tianyu Yang Dr. Zhiqiang Chen Dr. Neeraj Sharma Dr. Alexey M. Glushenkov Prof. Ying Chen 《Angewandte Chemie (International ed. in English)》2016,55(52):16059-16063
A simple, cost‐effective, and easily scalable molten salt method for the preparation of Li2GeO3 as a new type of high‐performance anode for lithium‐ion batteries is reported. The Li2GeO3 exhibits a unique porous architecture consisting of micrometer‐sized clusters (secondary particles) composed of numerous nanoparticles (primary particles) and can be used directly without further carbon coating which is a common exercise for most electrode materials. The new anode displays superior cycling stability with a retained charge capacity of 725 mAh g?1 after 300 cycles at 50 mA g?1. The electrode also offers excellent rate capability with a capacity recovery of 810 mAh g?1 (94 % retention) after 35 cycles of ascending steps of current in the range of 25–800 mA g?1 and finally back to 25 mA g?1. This work emphasizes the importance of exploring new electrode materials without carbon coating as carbon‐coated materials demonstrate several drawbacks in full devices. Therefore, this study provides a method and a new type of anode with high reversibility and long cycle stability. 相似文献
20.
Jingjuan Liu Yi Zhou Zhen Xie Yang Li Yunpeng Liu Jie Sun Yanhang Ma Osamu Terasaki Long Chen 《Angewandte Chemie (International ed. in English)》2020,59(3):1081-1086
A conjugated copper(II) catecholate based metal–organic framework (namely Cu‐DBC) was prepared using a D2‐symmetric redox‐active ligand in a copper bis(dihydroxy) coordination geometry. The π‐d conjugated framework exhibits typical semiconducting behavior with a high electrical conductivity of ca. 1.0 S m?1 at room temperature. Benefiting from the good electrical conductivity and the excellent redox reversibility of both ligand and copper centers, Cu‐DBC electrode features superior capacitor performances with gravimetric capacitance up to 479 F g?1 at a discharge rate of 0.2 A g?1. Moreover, the symmetric solid‐state supercapacitor of Cu‐DBC exhibits high areal (879 mF cm?2) and volumetric (22 F cm?3) capacitances, as well as good rate capability. These metrics are superior to most reported MOF‐based supercapacitors, demonstrating promising applications in energy‐storage devices. 相似文献