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Two-dimensional (2D) heterostructures combine the advantageous features of different 2D materials and represent advanced electrode architectures for the development of efficient energy storage devices. However, common 2D heterostructures made by stacking different 2D sheets in van der Waals (vdW) contact impose obvious limitations in light of the energy storage performance. Here, we shed light on how heterointerface conditions exert a great influence on the electrochemical properties of the heterostructured electrode and provide an example to modulate the interface contact mode via sandwiching unique g-C3N4 mesh (m-g-C3N4). We find that such m-g-C3N4 bonded heterointerfaces can greatly increase the electrochemical activity, redox conversion kinetics and structural integrity of the constituent component (NiS2), manifesting excellent electrochemical performance with respect to vdW heterostructures. Experimental characterization along with theoretical simulations demonstrates that the synergistic effects of the mesh-bonded interfacial contact and plenty of in-between porous channels contribute to superior electrochemical performance. This study directs attention to elaborate interface engineering toward high-performance energy storage and paves the way for designing and manufacturing of advanced heterostructured electrodes for supercapacitors, batteries and other hybrid devices.

NiCoO2 (NCO) with a desirable redox activity, high lithium storage capacity and distinct rock-salt structure has gained increasing attention toward application in next-generation lithium ion batteries (LIBs) in comparison with other transition metal oxides (TMOs). However, the volumetric change and pulverization of the NCO electrode during the charge/discharge processes hugely limit its utilization in LIBs. In this study, we present a novel assembling protocol via integrating different structural configurations to address the general limitations of TMO anodes, which effectively improves the rate and cycling performance of the NCO anode. In addition, we provide an insightful understanding of the electrochemical behaviors of NCO through various ex situ characterization techniques and first-principles DFT calculations for the first time. This study reveals that the inherent rock-salt phase character of NCO could not only preserve 3D channels toward efficient ionic/electrical interdiffusion, but also retain high electrochemical reversibility during the long cycling process in comparison to the spinel NiCo2O4. Potential application of the NCO anode for LIBs has also been evaluated through assembling full cells. This study demonstrates the synergistic influences of the innate structure of NCO and elaborate composite architecture on the performance, paving the way for future design and manufacture of TMO anodes for practical applications.

Lithium-sulfur (Li-S) batteries are one of the most promising candidates for meeting the emerging market demands for energy storage, and have the advantages including high energy density and low cost. However, the practical application of Li-S batteries is hindered by the lithium polysulfide (LiPS) shuttle, which induces low sulfur utilization and unsatisfactory capacity retention. To address this problem, recent studies have focused on improving the transformation of LiPS into insoluble Li2S2/Li2S through methods beyond physical or chemical adsorption. Nevertheless, the commonly used host materials have limited ability to simultaneously trap and propel redox transfer of LiPS. Herein, the bottom-up construction of new organic-inorganic hybrid frameworks for sulfur cathodes is proposed to fundamentally restrict LiPS dissolution and enhance their electrochemical transformation. The synergistic integration of organic cellulose networks and inorganic ZIF-derivatives caused highly efficient LiPS mediators to suppress the shuttle effect and retain electrode stability. The resulting RCE-Co3O4@G-S cathode materials delivered a stable capacity of 726.5 mA h g-1 at 0.2 C after 350 cycles, with a very low fading rate of 0.026% per cycle and a high coulombic efficiency of 98.9%.