Highly active nanostructured CoS2/CoS heterojunction electrocatalysts for aqueous polysulfide/iodide redox flow batteries
Highly active nanostructured CoS2/CoS heterojunction electrocatalysts for aqueous polysulfide/iodide redox flow batteries
复制标题
用于水性多硫化物/碘化物氧化还原液流电池的高活性纳米结构CoS2/CoS异质结电催化剂
DOI：
10.1038/s41467-019-11176-y
复制
发表时间：
2019-07-29
影响因子：
16.6
通讯作者：
Liu, T. Leo
中科院分区：
文献类型：
--
作者：
Ma, Dui;Hu, Bo;Liu, T. Leo
水性多硫化物/碘化物氧化还原液流电池由于其高能量密度和低成本而对于可扩展的能量存储是有吸引力的。然而，多硫/碘离子在石墨电极上氧化还原反应的电化学动力学性能较差，限制了其能量效率和功率密度，成为其实际应用的主要障碍。本文采用溶剂热法在石墨毡上原位合成了电荷分布不均匀的CoS 2/CoS异质结纳米粒子，通过提高荷电离子的吸收率和促进电荷转移，显著提高了I-/I-3（-）和S2-/S-x（2-）氧化还原反应的电催化活性。具有石墨烯毡-CoS 2/CoS异质结的多硫化物/碘化物液流电池可以在10 mA cm（-2）的电流密度、86.2 mW cm（-2）的功率密度下提供84.5%的高能量效率，并且在大约1000 h的连续操作后具有96%的稳定的能量效率保持率。
Aqueous polysulfide/iodide redox flow batteries are attractive for scalable energy storage due to their high energy density and low cost. However, their energy efficiency and power density are usually limited by poor electrochemical kinetics of the redox reactions of polysulfide/iodide ions on graphite electrodes, which has become the main obstacle for their practical applications. Here, CoS2/CoS heterojunction nanoparticles with uneven charge distribution, which are synthesized in situ on graphite felt by a one-step solvothermal process, can significantly boost electrocatalytic activities of I-/I-3(-) and S2-/S-x(2-) redox reactions by improving absorptivity of charged ions and promoting charge transfer. The polysulfide/iodide flow battery with the graphene felt-CoS2/CoS heterojunction can deliver a high energy efficiency of 84.5% at a current density of 10 mA cm(-2), a power density of 86.2 mW cm(-2) and a stable energy efficiency retention of 96% after approximately 1000 h of continuous operation.