Manipulating dehydrogenation kinetics through dual-doping Co3N electrode enables highly efficient hydrazine oxidation assisting self-powered H2 production
Manipulating dehydrogenation kinetics through dual-doping Co3N electrode enables highly efficient hydrazine oxidation assisting self-powered H2 production
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DOI：
10.1038/s41467-020-15563-8
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发表时间：
2020-04-15
影响因子：
16.6
通讯作者：
Zhang, Genqiang
中科院分区：
文献类型：
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作者：
Liu, Yi;Zhang, Jihua;Zhang, Genqiang
用肼氧化反应（HzOR）代替缓慢的析氧反应（OER）制氢被认为是比水裂解更节能的策略。然而，双电极系统中相对高的电池电压和所需的外部电力阻碍了其可扩展的应用，特别是在移动的设备中。在此，我们报道了一种双功能P，W共掺杂的Co 3 N纳米线阵列电极，其对HzOR（在10 mA cm（-2）下为-55 mV）和析氢反应（HER，在10 mA cm（-2）下为-41 mV）具有显著的催化活性。令人鼓舞的是，在双电极系统中需要28 mV的创纪录低电池电压来实现10 mA cm（-2）。密度泛函理论（DFT）计算表明，掺杂优化的H* 吸附/脱附和脱氢动力学可能是其潜在机制。重要的是，通过集成直接肼燃料电池与肼裂解电解槽的自供电H-2生产系统可以在室温下实现1.25 mmol h（-1）的体面速率。
Replacing sluggish oxygen evolution reaction (OER) with hydrazine oxidation reaction (HzOR) to produce hydrogen has been considered as a more energy-efficient strategy than water splitting. However, the relatively high cell voltage in two-electrode system and the required external electric power hinder its scalable applications, especially in mobile devices. Herein, we report a bifunctional P, W co-doped Co3N nanowire array electrode with remarkable catalytic activity towards both HzOR (-55 mV at 10 mA cm(-2)) and hydrogen evolution reaction (HER, -41 mV at 10 mA cm(-2)). Inspiringly, a record low cell voltage of 28 mV is required to achieve 10 mA cm(-2) in two-electrode system. DFT calculations decipher that the doping optimized H* adsorption/desorption and dehydrogenation kinetics could be the underlying mechanism. Importantly, a self-powered H-2 production system by integrating a direct hydrazine fuel cell with a hydrazine splitting electrolyzer can achieve a decent rate of 1.25 mmol h(-1) at room temperature.