ZIF-67-assisted construction of hollow core/shell cactus-like MnNiCo trimetal electrodes and Co, N dual-doped carbon electrodes for high-performance hybrid supercapacitors

et al. 2021

Batteries & Supercaps

Znic‐air (Zn‐air) cell has gained lots of attention due to its high specific energy. High activity and good stability of bifunctional electrocatalysts are very critical for Zn‐air cell. Herein, Co particles embedded in highly porous N‐doping carbon nanocube (Co/HP‐NC) has been successfully fabricated by pyrolyzing bimetallic Co/Zn‐zeolitic‐imidazolate framework (ZIF) and further evenly loaded with metallic Ru nanoparticles to obtain Ru‐coated Co/HP‐NC (Ru@Co/HP‐NC). Benefiting from introduction of Zn, Ru@Co/HP‐NC shows the large pore volume, small Co particles, high surface contents of Co4N and pyridinic/graphitic N. Furthermore, theoretical and experimental results further demonstrate that synergy of Ru coating with Co/HP‐NC can greatly improve the oxygen reduction/evolution reaction (ORR/OER) property of Ru@Co/HP‐NC. Furthermore, Ru@Co/HP‐NC based Zn‐air batteries present the high open circuit potential of 1.4 V, large power density of ∼210 mW cm−2, high discharge capacity (791 mAh g−1) and super‐long cycling life (∼475 cycles) with small overpotantials (∼0.89 V). Notably, flexible Zn‐air cell with Ru@Co/HP‐NC cathode also displays excellent flexibility and superior cycling stability under different bending conditions. The work provides the simple and reliable way to prepare high‐efficient electrocatalysts for high‐performance metal‐air systems.

Section: Resultssupporting

confidence: 65%

Ruthenium‐Modified Bimetallic Zeolitic‐Imidazolate Framework Derivative as a High‐Efficient Catalyst for Rechargeable Zinc‐Air Batteries

Feng

et al. 2021

Batteries & Supercaps

“…Metal–organic frameworks (MOFs) are 3D crystalline structures formed with the help of inorganic metal clusters, metal centers, organic linkers, and organometallic components, which have attracted interest in the fields of gas sorption, [ 17,18 ] drug delivery, [ 19,20 ] catalysis, [ 21,22 ] and energy storage [ 23,24 ] in recent years, owing to their distinct properties such as tunable porous structure, morphology, large specific surface area, distinct morphology and so on. [ 25 ] In concern to energy storage, the inferior conductivity of MOFs limit their energy storage applications, and thus researches significantly used MOFs as ideal sacrificial templates and precursors to derive various types of MOF‐derived nanomaterials to enhance the energy related properties.…”

Section: Introductionmentioning

confidence: 99%

“…Given the context of the global warming and excessive exploitation of nonrenewable fossil fuels, it is a great challenge and important necessity to advance sustainable and green energy storage technologies. Lithium-ion batteries (LIBs) with high energy density and ultralong lifespan have been spotlighted as exuberant candidates for energy storage in order to meet the which have attracted interest in the fields of gas sorption, [17,18] drug delivery, [19,20] catalysis, [21,22] and energy storage [23,24] in recent years, owing to their distinct properties such as tunable porous structure, morphology, large specific surface area, distinct morphology and so on. [25] In concern to energy storage, the inferior conductivity of MOFs limit their energy storage applications, and thus researches significantly used MOFs as ideal sacrificial templates and precursors to derive various types of MOF-derived nanomaterials to enhance the energy related properties.…”

Section: Introductionmentioning

confidence: 99%

Rational Design of Bimetallic Zeolitic Imidazolate Framework‐Derived C, N Dual‐Doped ZnO/Co for Boosting Lithium Storage

Advanced Sustainable Systems

Huang

et al. 2022

The advantages of LIBs are small size, light weight, low cost, high reversible capacity, long cycle performance, environmental friendliness as well as no memory effect. [3][4][5] Up to certain period of time, commercial graphite has been used for LIBs anodes. However, the graphite anode has to deal with issues, such as low charge storage capability (372 mAh g -1 ) due to the intercalation forming LiC 6 , [6] poor lithium-ion transport rate capability [7] and potential safety, [8] which hampers further application in LIBs. [9] Nowadays, transition metal oxides (TMOs), such as NiO, Fe 3 O 4 , Co 3 O 4 , ZnO, SnO 2 , etc., have been under a vigorous consideration by researchers as anode materials because of the low cost, widespread availability, environmental benignity, and much higher theoretical capacities (sometimes as high as several multitudes of commercial graphite) that they possess. [9,10] However, there still remain the limitations concerning all the TMOs, such as slower ion diffusion, low-capacity reservation, serious aggregation and drastic volume fluctuations during lithium insertion-deinsertion processes, ultimately causing the deformation of anode material, which limit their performances as lithium-ion batteries anodes. [11] There are several ways to overcome the above drawbacks. The first method is to explore the nanoarchitectures that will shorten the charge diffusion length and extend electronic pathway. [12] The second one is to construct special structures (such as hollow, yolk-shell, multishelled), which not only create large electrode-electrolyte contact sites but alleviate the volume changes during cyclic process. [13] Third, to mix multicomponent together is the promising strategy to have the benefit of synergistic effect. Thus, compared to single metal oxides, multicomponent materials favor more notable performance because of the possible synergistic effect. [14] After doping different metals, the metal of active materials can enhance the electrical conductivity and also serve as a catalytic agent, thus improving the electrochemical properties of whole electrode material. [15,16] Metal-organic frameworks (MOFs) are 3D crystalline structures formed with the help of inorganic metal clusters, metal centers, organic linkers, and organometallic components, Lithium-ion batteries (LIBs) are the preeminent technology for energy storage, having the highest energy density for large-scale commercial applications. Owing to üast assiduous studies, a good number of reported advanced anode materials possess excellent electrochemical properties. In this work, a porous C, N dual-doped ZnO/Co composite is successfully prepared by metalorganic frameworks (MOF)-template mediated synthesis method utilizing a self-sacrificing template of bimetallic zeolitic imidazolate framework (denoted as ZnCo-ZIF) and is tested as a lithium-ion battery anode material. Due to the advantageous structural and morphological features, such as well-defined open framework clusters with polyhedron crystal structure, conductive porous c...

“…Similar core‐shell structure is also observed in the LCCH‐Se@PBAs (Figure 1h) and the interplanar distances of 0.253, 0.261, 0.264, and 0.252 nm are indexed to the (221) plane of LCCH, (400) plane of PBAs, (111) plane of CoSe 2 and (120) plane of NiSe 2 , respectively (Figure 1i), while the Ni in Ni 9 S 8 and NiSe 2 are from the Ni foam, which is due to partial Ni can be doped in the products when LCCH grow on the surface of Ni foam directly. [ 22 ] Figure 1g,l are the related HAADF‐STEM images and EDS elemental mappings results of LCCH@PBAs, LCCH‐S@PBBAs, and LCCH‐Se@PBAs. Not surprisingly, Co, Ni, C, and N can be observed uniformly distributed on the surface of selected fields, while S and Se elements only observed over the LCCH wall, further demonstrating the interface connection of S and Se between core and shell.…”

Section: Resultsmentioning

confidence: 99%

Nonmetal (S or Se)‐Bridged Core Shell Electrodes for Promoting Electrochemical Performance

Wang

Sun

Advanced Energy Materials

et al. 2022

Self Cite

To meet strategic applications, rational design of advanced electrochemical materials would solve the poor electrochemical performance of core‐shell electrodes caused by the weak interfacial interaction between core and shell. Herein, two novel core‐shell electrodes LCCH‐S@PBAs and LCCH‐Se@PBAs are fabricated with a nonmetal (S or Se) bridging the core and shell. Electrochemical tests show that the as‐synthesized electrodes, especially LCCH‐S@PBAs, present higher mass‐specific capacitance with 10.1 C cm−2 at 1 mA cm−2, which is much better than that of PBA‐based homologs. Experimental results and theoretical calculations show that the bridging S or Se in the interface, not only tune electronic nature of the d‐states of metal ions in core and shell, but also form ionic bonds (M1(LCCH)‐S‐M2(PBAs) and M1(LCCH)‐Se‐M2(PBAs)) which facilitates the transmission of electrons, thus making a substantial enhancement of electrochemical performance via a dynamically more favorable pathway. The comparison with LCCH‐C@PBAs, in which the rGO is connected with core and shell by Van der Waals’ forces, also suggests the outstanding role of ionic bonds for electrochemical performance. This work proves that nonmetal bridging structures make a great contribution for enhanced electrochemical performance and demonstrates the large space to modulate the nonmetal bridging status for core‐shell structures in electrochemical materials.