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Designing multifunctional cathode materials is essential to address the critical issues of poor cycle stability and sluggish reaction kinetics in the aqueous zinc-ion batteries (AZIBs). Here, the spinel-type bimetallic MnCo 2 O 4 with a porous, layered, irregular cubic structure was synthesized using hydrothermal method, which was employed as a cathode material for high performance AZIBs. The design strategy involving bimetallic oxides offers more electrochemically active sites than monometallic oxides. Simultaneously, the unique porous structure of MnCo 2 O 4 facilitates faster ions and electrons transport, which alleviates the problems of volume expansion and structural collapse that occurring in the cathode material during cycling. As a result, the MnCo 2 O 4 electrode exhibits superior zinc storage performance with a high reversible specific capacity of 332.1 mAh g−1 and excellent cycle stability after 65 cycles at a current density of 0.3 A g−1. [Display omitted] • Irregular bimetallic MnCo 2 O 4 cubic structure with porous layered stacking were obtained by hydrothermal method. • MnCo 2 O 4 electrodes have both exceptional specific capacity and excellent cycling stability. • The Zn storage mechanism of MnCo 2 O 4 materials belongs to the H+/Zn2+ co-embedding/de-embedding process. [ABSTRACT FROM AUTHOR]

The 3D conducting network structure endows the superior cycle performance of MWCNTs/CF/Ni/NaCl composite for Na-NiCl 2 batteries cathode. • MWCNTs/CF/Ni/NaCl cathodes are prepared by the vacuum filtration technique. • MWCNTs/CF/Ni/NaCl cathodes possess high electronic conductivity. • The molar ratio of Ni/NaCl in the Na-NiCl 2 batteries cathode can be reduced to 1.0. • MWCNTs/CF/Ni/NaCl-1 electrode shows excellent long-term cycling performance. The sodium-nickel chloride (Na-NiCl 2) batteries technology has been considered as one of the most promising candidates for large-scale electrical energy storage application owing to its abundant electrode material resource, high energy density and safety. However, ultra-excessive Ni in the cathode leads to high material cost and the growth of cathode particles during cycles makes degradation of batteries performances, which hinder the further application of Na-NiCl 2 batteries. To address these challenges, we designed a free-standing Ni-less cathode with Ni/NaCl particles uniformly distributed in the three-dimensional (3D) conductive matrix constructed by carbonfiber (CF) and multiwalled carbon nanotubes (MWCNTs). The 3D hierarchical structure synthesized by low-cost vacuum filtration method can offer sufficient void space to accommodate the growth of NaCl particles and effectively enhance the electronic conductivity of the cathode. When the molar ratio of Ni/NaCl in the cathode is reduced to 1.0, a specific capacity of 90 mAh g−1 for planar Na-NiCl 2 batteries can be achieved after 170 cycles at 190 °C with a capacity retention of 67%, which is higher than that of traditional tubular Na-NiCl 2 batteries. [ABSTRACT FROM AUTHOR]