标题：Electrochemical Flocculation Integrated Hydrogen Evolution Reaction of Fe@N-Doped Carbon Nanotubes on Iron Foam for Ultralow Voltage Electrolysis in Neutral Media
作者：Yu, Jiayuan; Li, Guixiang; Liu, Hui; Zeng, Lili; Zhao, Lili; Jia, Jin; Zhang, Mingyuan; Zhou, Weijia; Liu, Hong; Hu, Yongyou
作者机构：[Yu, Jiayuan; Li, Guixiang; Liu, Hui; Zeng, Lili; Zhang, Mingyuan; Zhou, Weijia; Hu, Yongyou] South China Univ Technol, Guangzhou Key Lab Surface Chem 更多
通讯作者：Zhou, WJ;Hu, YY;Zhou, WJ
通讯作者地址：[Zhou, WJ; Hu, YY]South China Univ Technol, Guangzhou Key Lab Surface Chem Energy Mat, Key Lab Pollut Control & Ecosyst Restorat Ind Clu, Minist Educ, 更多
关键词：electrochemical flocculation; hydrogen evolution reaction; resource; recovery; water purification; water splitting
摘要：Hydrogen (H-2) production is a key step in solving the energy crisis in the future. Electrocatalytic water splitting suffers from sluggish anodic oxygen evolution reaction (OER) kinetics leading to low energy conversion efficiency. Herein, a strategy is presented that integrates anodic electrochemical flocculation with cathodic hydrogen production from water splitting in 0.5 m Na2SO4. Iron encapsulated in a nitrogen-doped carbon nanotubes array on iron foam (Fe@N-CNT/IF) is employed as an electrode for the hydrogen evolution reaction (HER), and the Fe@N-CNT/IF possesses superior HER activity requiring an overpotential of 525 mV to achieve 10 mA cm(-2), which is close to that of 20 wt% Pt/C. Benefiting from the lower oxidation potential of iron (E degrees(Fe/Fe2+), 0.44 V) than that of OER (E-OH-/O2(0), 1.23 V), the cell voltage for integrated electrochemical flocculation and H-2 production is significantly reduced by 1.31 V relative to overall water splitting to achieve 20 mA cm(-2). More important, the production of electrochemical flocculation can be applied to water purification, because of the excellent adsorption capacity. Finally, metal-carbon electrocatalysts are prepared again by pyrolysis of flocculation adsorbents containing toxic heavy metals and organics. This result provides a new direction for designing a heterogeneous electrolysis system for energy conversion and environmental treatment applications.