Division of Energy Storage, Dalian Institute of Chemical Physics, Chinese Academy of Sciences , Zhongshan Road 457, Dalian 116023, China.
Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) , Dalian 116023, China.
ACS Appl Mater Interfaces. 2017 Feb 8;9(5):4626-4633. doi: 10.1021/acsami.6b14478. Epub 2017 Jan 26.
Vanadium flow batteries (VFBs) have received high attention for large-scale energy storage due to their advantages of flexibility design, long cycle life, high efficiency, and high safety. However, commercial progress of VFBs has so far been limited by its high cost induced by its low power density. Ultrathin carbon paper is believed to be a very promising electrode for VFB because it illustrates super-low ohmic polarization, however, is limited by its low electrocatalytic activity. In this paper, a kind of carbon paper (CP) with super-high electrocatalytic activity was fabricated via a universal and simple CO activation method. The porosity and oxygen functional groups can be easily tuned via this method. The charge transfer resistance (denoting the electrochemical polarization) of a VFB with CP electrode after CO activation decreased dramatically from 970 to 120 mΩcm. Accordingly, the energy efficiency of a VFB with activated carbon paper as the electrode increased by 13% as compared to one without activation and reaches nearly 80% when the current density is 140 mAcm. This paper provides an effective way to prepare high-performance porous carbon electrodes for VFBs and even for other battery systems.
钒液流电池（VFBs）因其设计灵活、循环寿命长、效率高、安全性高等优点，在大规模储能方面受到高度关注。然而，VFB 的商业进展迄今为止一直受到其低功率密度导致的高成本的限制。超薄碳纸被认为是 VFB 非常有前途的电极，因为它具有超低欧姆极化，但受到其低电催化活性的限制。在本文中，通过一种通用且简单的 CO 活化方法制备了一种具有超高电催化活性的碳纸（CP）。通过这种方法可以轻松调节其孔隙率和含氧官能团。经过 CO 活化后，具有 CP 电极的 VFB 的电荷转移电阻（表示电化学极化）从 970 降至 120 mΩcm。因此，与未活化的 VFB 相比，以活化碳纸为电极的 VFB 的能量效率提高了 13%，当电流密度为 140 mAcm 时，能量效率接近 80%。本文为制备用于 VFB 甚至其他电池系统的高性能多孔碳电极提供了一种有效途径。
