The development of highly-efficient metal organic frameworks (MOFs) based supercapacitors has attracted much attention. In this work, hollow structured Ni/Co-MOFs have been facilely synthesized by using Co ions as the...

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Ultrathin 2D N-doped carbon nanosheets have been facilely synthesized by using GO as the structure-directing agent.

To overcome the shuttling effect and sluggish conversion kinetics of polysulfides, a large number of catalysts have been designed for lithium−sulfur (Li−S) batteries. Herein, a Mott−Schottky junction catalyst composed of Co nanoparticles and Ni 2 P was designed to improve polysulfide kinetics. Our investigations reveal the rearrangement of charges at the Schottky junction interface and the construction of the built-in electric field are crucial for lowering the activation energy of the dissolved Li 2 S n reduction and Li 2 S nucleation reaction. Furthermore, a series of experimental and electrochemical tests were performed to demonstrate that the Schottky catalytic effect enhanced the synergistic catalytic effect. With a Ni 2 P−Co@CNT catalyst, the battery exhibits an initial specific capacity of 874 mAh g −1 at a rate of 4.0 C, and the decay rate per cycle is 0.049% in 700 cycles. Meanwhile, the battery shows 0.118% decay rate per cycle at 0.5 C in 100 cycles at a high sulfur loading of 10 mg cm −2 . The Schottky heterojunction structure proposed here has been shown to have a good catalytic effect on the reduction of Li 2 S n and nucleation of Li 2 S, which provides a profound guidance for efficient and rational catalyst design.

N-Doped hollow carbon materials have been fabricated via the carbonization process by using ZIF-8 coated with PDA.

1D/2D nanohybrids composed of NiCo-hydroxide nanowires and graphene have been successfully fabricated by a simple method.

The insufficient contact between two phases in the heterostructure weakens the coupling interaction effect, which makes it difficult to effectively improve the electrochemical performance. Herein, a Co‐carbonate hydroxide@ Ni‐metal organic frameworks (Co‐CH@Ni‐MOFs) composite with super uniform core‐shell heterostructure is fabricated by adopting 1D Co‐CH nanowires as structuredirecting agents to induce the coating of Ni‐MOFs. Both experimental and theoretical calculation results demonstrate that the heterostructure plays a vital role in the high performance of the as‐prepared materials. On the one hand, the construction of super uniform core‐shell heterostructure can create a large number of interfacial active sites and take advantages of the electrochemical characteristics of each component. On the other hand, the heterostructure can increase the adsorption energy of OH– ions and promote the electrochemical activity for improving the reversible redox reaction kinetics. Based on the aforementioned advantages, the as‐fabricated Co‐CH@Ni‐MOFs electrode exhibits a high specific capacity of 173.1 mAh g−1 (1246 F g−1) at 1 A g−1, an ultrahigh rate capability of 70.3% at 150 A g−1 and excellent cycling stability with 90.1% capacity retention after 10 000 cycles at 10 A g−1. This study may offer a versatile design for fabricating a MOFs‐based heterostructure as energy storage electrodes.

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