Institute of Energy Technology, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, 305-8568 (Japan).
ChemSusChem. 2015 Apr 24;8(8):1429-34. doi: 10.1002/cssc.201403371. Epub 2015 Mar 25.
Porous carbon-free cathodes are critical to achieve a high discharge capacity and efficient cycling for rechargeable Li-O2 battery. Herein, we present a very simple method to directly grow nanoporous Ru (composed of polycrystalline particles of ∼5 nm) on one side of a current collector of Ni foam via a galvanic replacement reaction. The resulting Ru@Ni can be employed as a carbon- and binder-free cathode for Li-O2 batteries and delivers a specific capacity of 3720 mAh gRu (-1) at a current density of 200 mA gRu (-1) . 100 cycles of continuous discharge and charge are obtained at a very narrow terminal voltage window of 2.75∼3.75 V with a limited capacity of 1000 mAh gRu (-1) . The good performance of the nanoporous Ru@Ni cathode can be mainly attributed to the effective suppression of the by-products related to carbon or binder, the good adhesion of the catalyst to the current collector, and the good permeation of O2 and electrolyte into the active sites of the nanoporous Ru with the open pore system. This new type electrode provides a snapshot toward developing high-performance carbon- and binder-free Li-O2 batteries.
无碳多孔阴极对于实现可再充电 Li-O2 电池的高放电容量和高效循环至关重要。在此，我们提出了一种非常简单的方法，通过电置换反应直接在 Ni 泡沫集流体的一侧生长纳米多孔 Ru（由约 5nm 的多晶颗粒组成）。所得的 Ru@Ni 可用作 Li-O2 电池的无碳和无粘结剂阴极，在 200mA·gRu-1 的电流密度下可提供 3720mAh·gRu-1 的比容量。在 2.75∼3.75V 的非常窄的端电压窗口下，可获得 100 次连续放电和充电循环，具有 1000mAh·gRu-1 的有限容量。纳米多孔 Ru@Ni 阴极的良好性能主要归因于有效抑制与碳或粘结剂有关的副产物、催化剂与集流体的良好附着力以及 O2 和电解质在具有开放孔系统的纳米多孔 Ru 的活性位点中的良好渗透。这种新型电极为开发高性能无碳和无粘结剂 Li-O2 电池提供了一个新的视角。
