Cross-linked hierarchical arrays of Ni2P nanoflakes prepared via directional phosphorization and their applications for advanced alkaline batteries

In this work, we report a facile directional phosphorization method for construction of hierarchical cross linked Ni2P arrays, which show a multileveled porous architecture. The basic building blocks are numerous nanoflakes with thicknesses of 15-20 nm, which are self-assembled with each other forming the primary porous mushroom-like structure with 1-3 mu m. Impressively, the 3D porous channels run through the whole Ni2P arrays. The secondary nanoflakes consist of interconnected nanoparticles of 10 30 nm and lots of nanopores of 10-50 nm. The electrochemical performance of the as-prepared Ni2P arrays is investigated as cathode of alkaline batteries and demonstrated with higher capacities (127 mAhh g(-1) at 2.5 A g(-1)) and better high-rate cycling stability (123 mAhh g(-1) 2.5 A g(-1) after 9000 cycles) than the preformed Ni(OH)(2) arrays counterparts (80 mAhh g-1 2.5 A g(-1) and 66 mAhh g(-1) after 9000 cycles). The enhanced performance is mainly due to the improved surface area & porosity as well as reinforced electrical conductivity. (C) 2017 Elsevier B.V. All rights reserved.