%0 Journal Article
%T Revealing molecular-level surface redox sites of controllably oxidized black phosphorus nanosheets
%J -
%D 2018
%R https://doi.org/10.1038/s41563-018-0230-2
%X Bulk and two-dimensional black phosphorus are considered to be promising battery materials due to their high theoretical capacities of 2,600£¿mAh g£¿1. However, their rate and cycling capabilities are limited by the intrinsic (de-)alloying mechanism. Here, we demonstrate a unique surface redox molecular-level mechanism of P sites on oxidized black phosphorus nanosheets that are strongly coupled with graphene via strong interlayer bonding. These redox-active sites of the oxidized black phosphorus are confined at the amorphorized heterointerface, revealing truly reversible pseudocapacitance (99% of total stored charge at 2,000£¿mV£¿s£¿1). Moreover, oxidized black-phosphorus-based electrodes exhibit a capacitance of 478£¿F£¿g¨C1 (four times greater than black phosphorus) with a rate capability of ~72% (compared to 21.2% for black phosphorus) and retention of ~91% over 50,000 cycles. In situ spectroelectrochemical and theoretical analyses reveal a reversible change in the surface electronic structure and chemical environment of the surface-exposed P redox sites
%U https://www.nature.com/articles/s41563-018-0230-2