Co-intercalation of multiple active units into graphene by pyrolysis of hydrogen-bonded precursors for zinc-air batteries and water splitting
Co-intercalation of multiple active units into graphene by pyrolysis of hydrogen-bonded precursors for zinc-air batteries and water splitting
复制标题
通过锌空气电池氢键前体的热解和水分解将多个活性单元共嵌入石墨烯中
DOI：
10.1039/c7ta06677e
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发表时间：
2017-10-21
影响因子：
11.9
通讯作者：
Wang, Yaobing
中科院分区：
文献类型：
--
作者：
Huang, Yiyin;Liu, Qin;Wang, Yaobing
多功能电催化氢/氧电化学氧化还原在可变能量转换/储存装置和一些耦合装置中起着关键作用。目前开发多功能电催化剂的艰巨挑战是将多个活性位点有效地结合到一种材料中。在本文中，我们提出了一种通过可控热解/蒸气重整过程的一般方案，其允许重构以形成CoNC纳米单元，同时保留Co和Co氧化物。通过将这些活性单元共插入石墨烯中，该材料产生突出的三功能活性。析氢和析氧反应的过电位分别为205和360 mV（10 mA cm（-2）），氧还原反应的半波电位为0.81 V，优于大多数最先进的三功能电催化剂。在锌空气电池中实现了23 mW cm（-2）的最大功率密度和1000次稳定循环。该电池进一步驱动整体水裂解24小时，法拉第效率约为1.5%。100%，产气速率分别为0.035和0.017 mL min（-1）。因此，这项工作提供了一个通用的方法，以探索其他有效的多功能电催化剂在可再生能源技术的应用。
Multifunctional electrocatalyst enabled electrochemical hydrogen/oxygen redox plays pivotal roles in variable energy conversion/storage devices and some coupling devices. The daunting challenge in developing multifunctional electrocatalysts at present is to effectively incorporate multiple active sites into one material. Herein, we presented a general protocol by a controllable pyrolysis/vapor reforming process, which allows for reconstitution to form CoNC nano-units, while preserving Co and Co oxides simultaneously. The material by co-intercalation of these active units into graphene generates outstanding trifunctional activities. The overpotentials for hydrogen and oxygen evolution reactions are 205 and 360 mV (at 10 mA cm(-2)), respectively, and the half-wave potential for the oxygen reduction reaction is 0.81 V, outperforming most of the state-of-the-art trifunctional electrocatalysts. A maximum power density of 23 mW cm(-2) and 1000 stable cycles were realized in the as-prepared material equipped Zn-air battery. This battery further drove overall water splitting for 24 hours, at a faradaic efficiency of ca. 100% and gas production rate of 0.035 and 0.017 mL min(-1) for hydrogen and oxygen, respectively. Thus this work offers a general approach to explore other efficient multifunctional electrocatalysts for application in renewable energy technologies.