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A MOF-based sacrificial template strategy is demonstrated to construct novel Mo-doped Co(OH) 2 hierarchical nanotubes organized by cross-linked porous nanosheets with the optimized electronic structure of more highly oxidative Co3+ species, which exhibits active and stable electrocatalytic activity for overall water splitting. • The Mo-doped Co(OH) 2 HNTs organized by cross-linked porous nanosheets are prepared. • Electronic structures with highly oxidative Co3+ species can be modified by Mo doping. • The low overpotentials of 218 mV and 125 mV for OER and HER are obtained. • Mo-Co(OH) 2 HNTs exhibit high electrocatalytic activity for overall water splitting. Designing hierarchical nanostructures of earth-abundant electrocatalysts for enhanced overall water splitting performance is of great significance. Herein, Mo-doped Co(OH) 2 hierarchical nanotubes (Mo-Co(OH) 2 HNTs) assembled by cross-linked porous nanosheets are designed and synthesized through a sacrificial template strategy. Benefiting from the hierarchical structures based on porous nanosheets with void interior as well as modified electronic structure of higher intensity of Co3+ species by Mo6+ doping, the Mo-Co(OH) 2 HNTs demonstrate superior electrocatalytic performance, achieving an current density of 10 mA cm−2 at the low overpotentials of 218 mV and 125 mV for oxygen and hydrogen evolution reactions, respectively. Furthermore, an overall water splitting cell was assembled with the Mo-Co(OH) 2 electrocatalyst as both the anode and cathode materials, which exhibits a driving voltage of as low as 1.62 V. The facile strategy presented in this work can be extended to the construction of various hollow/porous nanostructures with effective heteroatom doping to achieve low-cost, bifunctional and high-performance electrocatalysts for overall water splitting. [ABSTRACT FROM AUTHOR]

[Display omitted] The commercialization of lithium–sulfur (Li–S) batteries is challenging, owing to factors like the poor conductivity of S, the 'shuttle effect', and the slow reaction kinetics. To address these challenges, MoP quantum dots were decorated on hollow carbon spheres (MoPQDs/C) in this study and used as an efficient lithium polysulfides (LiPSs) adsorbents and catalysts. In this approach polysulfides are effectively trapped through strong chemisorption and physical adsorption while simultaneously facilitating LiPSs conversion by enhancing the reaction kinetics. MXene serves as a flexible physical barrier (MoPQDs/C@MXene), further enhancing the confinement of LiPSs. Moreover, both materials are conductive, significantly facilitating electron and charge transfer. Additionally, the flexible MoPQDs/C@MXene–S electrode offers a large specific surface area for sulfur loading and withstand volume expansion during electrochemical processes. As a result, the MoPQDs/C@MXene–S electrode exhibits excellent long-term cyclability and maintains a robust specific capacity of 992 mA h g−1 even after 800cycles at a rate of 1.0C (1C = 1675 mA g−1), with a minimal capacity decay rate of 0.034 % per cycle. This work proposes an efficient strategy to fabricate highly efficient electrocatalysts for advanced Li–S batteries. [ABSTRACT FROM AUTHOR]