Zhao Chang-Xin, Liu Jia-Ning, Wang Juan, Ren Ding, Yu Jia, Chen Xiao, Li Bo-Quan, Zhang Qiang
Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing, 100084, China.
School of Materials Science and Engineering, Beijing Institute of Technology, Beijing, 100081, China.
Adv Mater. 2021 Apr;33(15):e2008606. doi: 10.1002/adma.202008606. Epub 2021 Mar 3.
Rechargeable zinc-air batteries constitute promising next-generation energy storage devices due to their intrinsic safety, low cost, and feasibility to realize high cycling current density and long cycling lifespan. Nevertheless, their cathodic reactions involving oxygen reduction and oxygen evolution are highly sluggish in kinetics, requiring high-performance noble-metal-free bifunctional electrocatalysts that exceed the current noble-metal-based benchmarks. Herein, a noble-metal-free bifunctional electrocatalyst is fabricated, which demonstrates ultrahigh bifunctional activity and renders excellent performance in rechargeable zinc-air batteries. Concretely, atomic Co-N-C and NiFe layered double hydroxides (LDHs) are respectively selected as oxygen reduction and evolution active sites and are further rationally integrated to afford the resultant CoNC@LDH composite electrocatalyst. The CoNC@LDH electrocatalyst exhibits remarkable bifunctional activity delivering an indicator ΔE of 0.63 V, far exceeding the noble-metal-based Pt/C+Ir/C benchmark (ΔE = 0.77 V) and most reported electrocatalysts. Correspondingly, ultralong lifespan (over 3600 cycles at 10 mA cm ) and excellent rate performances (cycling current density at 100 mA cm ) are achieved in rechargeable zinc-air batteries. This work highlights the current advances of bifunctional oxygen electrocatalysis and endows high-rate and long-cycling rechargeable zinc-air batteries for efficient sustainable energy storage.
可充电锌空气电池因其本质安全性、低成本以及实现高循环电流密度和长循环寿命的可行性，而成为很有前景的下一代储能装置。然而，其涉及氧还原和析氧的阴极反应动力学非常缓慢，需要高性能的无贵金属双功能电催化剂，其性能要超过目前基于贵金属的基准。在此，制备了一种无贵金属双功能电催化剂，它表现出超高的双功能活性，并在可充电锌空气电池中呈现出优异的性能。具体而言，分别选择原子级的Co-N-C和NiFe层状双氢氧化物（LDHs）作为氧还原和析氧活性位点，并进一步合理整合，得到CoNC@LDH复合电催化剂。CoNC@LDH电催化剂表现出显著的双功能活性，其指示ΔE为0.63 V，远远超过基于贵金属的Pt/C+Ir/C基准（ΔE = 0.77 V）以及大多数已报道的电催化剂。相应地，可充电锌空气电池实现了超长寿命（在10 mA cm下超过3600次循环）和优异的倍率性能（在100 mA cm下的循环电流密度）。这项工作突出了双功能氧电催化的当前进展，并为高效可持续储能赋予了高倍率和长循环的可充电锌空气电池。
