| 초록 |
One of the most difficult challenges related to oxide nanoparticle (NP)-based energy storage electrodes is overcoming the sluggish charge transfer, which results from the poorly conductive NPs and bulky/insulating organics. Herein, we report that the physical/chemical functionalities of organic ligands have a decisive effect on the charge transfer of oxide NP-based electrodes. To this end, pseudocapacitive Fe3O4 NPs are alternatively deposited with conductive ITO NPs based on the layer-by-layer assembly using various types of ligands (or linkers). Particularly, hydrazine ligands with extremely small molecular size and reducing properties can effectively eliminate bulky native ligands from the NP surface, and thus markedly reduce the inter-particle distance. The hydrazine ligands also increase the ratio of oxygen vacancies on the oxide NPs, which enhances the rate capability and capacitance of the electrodes compared to other ligands with a bulky size and/or without reducing properties. |
